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Eating in the lockdown during the Covid 19 pandemic; self-reported changes in eating behaviour, and associations with BMI, eating style, coping and health anxiety.
Coulthard, H, Sharps, M, Cunliffe, L, van den Tol, A
Appetite. 2021;161:105082
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The Covid-19 pandemic resulted in national lockdowns, which resulted in isolation within people’s homes. This cross-sectional survey examined changes in eating patterns and behaviour during lockdown. Of the 620 participants included in the study, eating higher energy density foods was more common in females with a higher BMI and higher health anxiety. Although there was a change in emotional eating behaviours across the sample as a whole, it was not in the expected direction, with many participants reporting a decrease in emotional eating after the implementation of lockdown. There were also increases in fruit and vegetable consumption and home prepared foods. Many of these behavioural responses were influenced by pre-lockdown tendencies. Therefore, it is important to consider these when understanding coping strategies during lockdown, and how to support clients as we come out of lockdown.
Expert Review
Conflicts of interest:
None
Take Home Message:
- National lockdowns, as seen during the 2020/21 Covid-19 pandemic, impacted eating behaviour and associations with BMI, eating style and health anxiety.
- Given the new nature of this research, it is not clear what impact confounding factors such as food insecurity had on changing eating behaviours.
- Disproportionate risks were seen in certain demographics and in those shielding due to their heightened risk from Covid-19.
- Retrospective and longitudinal studies to monitor the impact of lockdowns on eating behaviour and health anxiety are needed.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
The role of eating behaviours and psychological responses during lockdown has become an area of interest, particularly with the uncertainty of going into future lockdowns. With Covid-19, and individual’s responses to it, being a relatively new research topic, there is not yet enough evidence for longitudinal outcomes of the findings in these studies. It is also difficult to ascertain the influence of confounding variables prior to the national lockdown, such as food insecurity, not accounted for due to the unpredictable start to the pandemic. There has also been disproportionate risks between certain demographics and their Covid-19 risk, therefore further research on the impact of this on health anxiety and subsequent eating behaviours is required. This highlights a wider need for continued research on the topic.
Clinical practice applications:
Those who had problematic eating behaviours and higher BMI pre lockdown will need to be supported with healthier coping practices if subsequent lockdowns occur, to prevent health related anxiety and consumption of high energy density foods. Furthermore, those who were shielding in their homes were also more likely to show an increase in emotional eating post lockdown. Therefore, clients who spent a large amount of lockdown shielding will need additional support, to develop coping strategies to prevent risk of emotional eating and health anxiety.
Considerations for future research:
Both retrospective and longitudinal studies monitoring the impact of eating behaviours and health anxiety pre and post lockdown are needed. This will help further the evidence base of the potential role of Covid-19 related health anxiety on eating patterns, coping strategies and dietary choices.
Abstract
The global coronavirus pandemic (Covid 19) resulted in national lockdowns where individuals were asked to isolate in their homes to stop the spread of the disease. Using a cross-sectional survey, the current paper aimed to examine self-reported changes in eating patterns and behaviour during the lockdown in the UK, and associations with BMI, demographic variables, eating styles, health anxiety, food insecurity and coping strategies. Participants (N = 620) were recruited online through social media advertising. The results showed that there were self-reported changes to food consumption during the lockdown across the sample. Increases in consumption of HED (high energy density) snack foods during the lockdown was associated with sex, pre-lockdown eating behaviour (emotional eating and uncontrolled eating), and Covid-specific health anxiety. Increases in positive eating practices such as eating more home prepared foods, and fruits and vegetables, were associated with adaptive coping strategies. Higher emotional eating (EE) during the lockdown was associated with a higher BMI, higher pre-lockdown EE and maladaptive coping strategies. Maladaptive coping strategies moderated the relationship between BMI and EE during the lockdown. In particular a higher BMI was associated with higher EE during the lockdown if an individual also had higher maladaptive coping strategies. These findings suggest that changes to eating behaviour may be part of a wider style of maladaptive or adaptive coping, particularly in those with a history of EE or uncontrolled eating. Preparing individuals to adopt more adaptive coping strategies during lockdown situations may be crucial to improving health during subsequent the lockdown events.
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Intake and adequacy of the vegan diet. A systematic review of the evidence.
Bakaloudi, DR, Halloran, A, Rippin, HL, Oikonomidou, AC, Dardavesis, TI, Williams, J, Wickramasinghe, K, Breda, J, Chourdakis, M
Clinical nutrition (Edinburgh, Scotland). 2021;40(5):3503-3521
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This systematic review investigated vegan diets in the European populations and their adequacy of macro-and micronutrient intake, compared to the recommendations of the World Health Organization. Included were 48 studies and their outcomes regarding protein, carbohydrates, fats and micronutrients summarized. The overall results and their impact on health are discussed in the later sections of the paper. Adequate intake amongst vegans was seen with carbohydrates, fats, Vitamin A, B1, В6, C, E, iron, phosphorus, magnesium, copper and folate. Sodium exceeded recommended intake, whilst protein, Vitamin B2, B3, B12, D, iodine, zinc, calcium, potassium, selenium was of low consumption in a vegan diet. The bioavailability of some nutrients was also acknowledged. In summary, following a vegan diet appears to have positive and negative aspects. A vegan diet profile can contribute to disease prevention with lower incidence rates of obesity, Type 2 diabetes, and cardiovascular disease. Yet veganism appears to increase the risk for mental health conditions, bone fractures, immune system impairments, anaemias and deficiencies from low nutrient intake. This review yields a comprehensive overview of the positive and negative health consequences of a vegan diet. It may be a useful reference for those looking to support vegans or individuals considering adopting a vegan diet pattern.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Vegan diets in European populations tend to be lower in protein intake, particularly amino acids lysine, methionine and tryptophan.
- Other micronutrients that tend to lower in vegan diets are Vitamin B12, zinc, calcium and selenium.
- Healthcare practitioners should be aware of these potential deficiencies when working with vegan clients.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Vegan diets have become increasingly popular in the last ten years. This systematic review of 48 studies investigated the adequacy of vegan diets in European populations. It compared their macro- and micronutrient intakes compared to World Health Organization recommendations. It found that vegan diets tend to be lower in protein and in essential amino acids (lysine, methionine and tryptophan). They can also be lower in micronutrients especially vitamin B12, zinc, calcium and selenium. However, the lower intakes are not always associated with health impairments.
Clinical practice applications:
Practitioners should be aware of the potential deficiencies in a vegan diet.
Considerations for future research:
More research is needed to determine whether lower nutrient intakes in vegans correlated with poor health outcomes.
Abstract
BACKGROUND Vegan diets, where animal- and all their by-products are excluded from the diet, have gained popularity, especially in the last decade. However, the evaluation of this type of diet has not been well addressed in the scientific literature. This study aimed to investigate the adequacy of vegan diets in European populations and of their macro- and micronutrient intakes compared to World Health Organization recommendations. METHODS A systematic search in PubMed, Web of Science, IBSS, Cochrane library and Google Scholar was conducted and 48 studies (12 cohorts and 36 cross-sectional) were included. RESULTS Regarding macronutrients, vegan diets are lower in protein intake compared with all other diet types. Veganism is also associated with low intake of vitamins B2, Niacin (B3), B12, D, iodine, zinc, calcium, potassium, selenium. Vitamin B12 intake among vegans is significantly lower (0.24-0.49 μg, recommendations are 2.4 μg) and calcium intake in the majority of vegans was below recommendations (750 mg/d). No significant differences in fat intake were observed. Vegan diets are not related to deficiencies in vitamins A, B1, Β6, C, E, iron, phosphorus, magnesium, copper and folate and have a low glycemic load. CONCLUSIONS Following a vegan diet may result in deficiencies in micronutrients (vitamin B12, zinc, calcium and selenium) which should not be disregarded. However, low micro- and macronutrient intakes are not always associated with health impairments. Individuals who consume a vegan diet should be aware of the risk of potential dietary deficiencies.
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Igg Food Antibody Guided Elimination-Rotation Diet Was More Effective than FODMAP Diet and Control Diet in the Treatment of Women with Mixed IBS-Results from an Open Label Study.
Ostrowska, L, Wasiluk, D, Lieners, CFJ, Gałęcka, M, Bartnicka, A, Tveiten, D
Journal of clinical medicine. 2021;10(19)
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IBS, also known as irritable bowel syndrome, is a debilitating condition characterised by abdominal pain, irregular bowel movements, and changes in the consistency of stool. Symptoms of IBS may appear shortly after eating a meal. Excluding foods high in FODMAP carbohydrates, such as fermentable oligo- and di-saccharides, mono- and disaccharides, and polyols, or following an elimination rotation diet to reduce IgG-dependent food hypersensitivity, which has been shown to improve IBS symptoms previously. The purpose of this open-label study is to investigate the effectiveness of a low-FODMAPS diet and an elimination rotation diet based on IgG as well as a control diet in reducing symptoms of IBS. During the eight-week study, 73 female subjects with a mix of IBS were assigned to either of the three dietary treatments. Compared to the other diet groups, the IgG based elimination rotation diet group showed a significant improvement in the IBS symptoms and comorbid symptoms after the intervention period. In order to determine whether IgG-mediated food hypersensitivity plays a role in IBS and the efficacy of an IgG-dependent elimination rotation diet in the general population, further robust research is required. Healthcare professionals, however, can make use of these results to gain a better understanding of how an IgG based elimination diet tailored to each individual can improve IBS symptoms.
Expert Review
Conflicts of interest:
None
Take Home Message:
- After implementing the three diets, among patients with IBS-M, a statistically significant reduction of the frequency of the idiopathic abdominal pain, abdominal pain after a meal, abdominal pain during defecation, and sensation of incomplete defecation before and after the diet plans, were only found in Group 2.
- Significantly, only in the Group 2 IgG based elimination-rotation-diet was there a high decrease or complete disappearance of dyspeptic IBS symptoms and co-morbidities together with IBS symptoms.
- This study shows that a personalised dietary approach is more effective in treating IBS than generalised diet recommendations, with elimination diets focused on IgG antibodies providing the best results.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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X
C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Science supports the use of a low-FODMAP diet for symptom relief of IBS. However, more recently evidence suggests that IBS is a low-grade inflammatory disease that may result from or lead to IgG-dependent food hyper-sensitivities.
This study compared the effectiveness of three dietary treatment plans in 73 female patients diagnosed with mixed-form IBS based on Rome III criteria and no other gastrointestinal condition over 8 weeks.
The 3 dietary groups were:
- Group 1-low FODMAP diet
- Group 2- IgG based elimination-rotation-diet
- Group 3-control diet (control group)
Diets of G1 and G2 were determined individually by a dietitian, based on low-FODMAP dietary information and results from IgG food sensitivity testing respectively. Group 3 received nutrition advice from a gastroenterologist.
In G1, some of the IBS symptoms significantly improved (mucus in stool, p = 0.031; bloating, p < 0.001). Gurgling sensation and gastric fullness also reach statistical significance in G1.
IBS symptoms as well as co-morbid symptoms significantly improved or disappeared completely in G2 (idiopathic abdominal pain, p < 0.001; abdominal pain after a meal, p < 0.001; abdominal pain during defecation, p = 0.008; sensation of incomplete defecation p = 0.001; difficulty to defecate (constipation) p = 0.002; bloating p = < 0.001; gurgling sensation < 0.001; gastric fullness p = < 0.001. However, blood and mucus in the stool were impossible to test because the symptoms were not reported by any patient during the 2nd examination). (p-values less than 0.05 were considered statistically significant).
In group G3 no statistically significant improvements were seen in any measure.
Based on the results of this open-label study, it was concluded that personalised dietary interventions were more effective in the treatment of IBS-M patients than generalised diet recommendations. Dietary elimination based on IgG food sensitivity test results had the greatest impact on IBS and related symptoms.This study supports results from other studies showing an IgG-guided diet as an effective strategy in co-morbid conditions such as fatigue, headache/migraine, and skin conditions.
Conflicts of Interest
C.F.J.L., M.G. and A.B. are employees of the Institute of Microecology in Poznan ,where the ImuPro tests were determined. D.T. is the Head of Laboratory and shareholder of Lab1, offering ImuPro tests in Norway.
Clinical practice applications:
- Low FODMAP diets studies (NICE) showed GI improvements for abdominal pain, abdominal cramps, diarrhoea, gas, and bloating, largely because FODMAPs mainly cause an excessive production of gas, leading to discomfort and pain and an increased osmotic effect leading to increased bowel movement and diarrhoea. However 30% of patients still suffered from bloating on the FODMAP diet. Gurgling sensation decreased from 65% to 15%, and gastric fullness decreased from 58% to 11% in the patients on the low FODMAP diet.
- A potential new approach to resolve functional symptoms of gastrointestinal conditions could be to start with an IgG-guided elimination diet, as it was proven to be the more effective diet in this open study, and in cases of persistent symptoms, it could be combined with a low-FODMAP diet.
- Calprotectin is currently one of the best-known diagnostic markers indicating mucosa inflammation and changes in the inflammation intensity. In this study serious intestinal inflammation was diagnosed at the faecal calprotectin concentration of >50 mg/kg of stool. During the first examination, no statistically significant differences were found in calprotectin concentrations between the compared groups of patients, and the values were low, suggesting that the included patients suffered from low-grade inflammation and were suitable for diet alteration as the best choice of treatment.
Limitations:
- The main limitations of this study are the open-labeled nature, the low number of participants and the bias of only including female participants with only the patients in the G2 group tested for IgG food antibodies.
- Foods consumed by the patients before they entered the study were not ascertained.
Considerations for future research:
- Claims that IgG food antibodies only reveal exposure to food and not intolerance should be reinvestigated in larger double-blinded studies.
Abstract
Irritable bowel syndrome (IBS) is a chronic disease with recurrent abdominal pain, disturbed bowel emptying, and changes in stool consistency. We compared the effectiveness of three different dietary treatment plans (G1-FM-low FODMAP diet, G2-IP IgG based elimination-rotation-diet, and as control group, the G3-K control diet recommended by an attending gastroenterologist) in treating patients diagnosed with mixed irritable bowel syndrome. A total of seventy-three female patients diagnosed with a mixed form of irritable bowel syndrome (IBS-M) were enrolled in the study. The diet of each patient in Group 1 (G1-FM) and 2 (G2-IP) was determined individually during a meeting with a dietitian. Patients from Group 3 (G3-K) received nutrition advice from a gastroenterologist. Significant differences in the reduction of IBS symptoms were found between the groups. IBS symptoms as well as comorbid symptoms significantly improved or disappeared completely in the G2-IP group (idiopathic abdominal pain, p < 0.001; abdominal pain after a meal, p < 0.001; abdominal pain during defecation, p = 0.008), while in the G1-FM group, some of the IBS symptoms significantly improved (mucus in stool, p = 0.031; bloating, p < 0.001). In group G3-K no significant improvement was seen. Based on the results of this open-label study, it was concluded that various dietary interventions in the treatment of IBS-M patients do not uniformly affect the course and outcomes of disease management. Rotation diets based on IgG show significantly better results compared to other diets.
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Efficacy and safety of low and very low carbohydrate diets for type 2 diabetes remission: systematic review and meta-analysis of published and unpublished randomized trial data.
Goldenberg, JZ, Day, A, Brinkworth, GD, Sato, J, Yamada, S, Jönsson, T, Beardsley, J, Johnson, JA, Thabane, L, Johnston, BC
BMJ (Clinical research ed.). 2021;372:m4743
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Diet modification has long been recognised as a component for the treatment of diabetes. Diets low in carbohydrates have been extensively researched, as a diet for those with Type 2 Diabetes (T2D). This systematic review and meta-analysis aimed to determine the effect of low carbohydrate diets on T2D. The systematic review found 23 studies, including 1357 individuals, investigating the role of low carbohydrate diets on T2D outcomes. Low carbohydrate diet was defined as less than 130g of carbohydrate (less than 26% of calories from carbohydrate) for at least 12 weeks. Results reported at 6 months, found low carbohydrate diets were more effective than a normal diet at achieving diabetes remission. However, this effect diminished at 12 months, although longer term improvements were seen in blood lipids, weight loss and measures of prediabetes. It was concluded that individuals with T2D, eating a low carbohydrate diet for 6 months may reverse the disease. This study could be used by healthcare professionals to recommend a short-term low carbohydrate diet to individuals with T2D, to improve their chance of going into remission.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Type 2 diabetes remains a significant and worsening problem worldwide, despite many pharmaceutical developments and a global emphasis on glycemic control.
- This review highlights structured LCDs as a worthwhile option for the management and treatment of diabetes, providing an opportunity for Nutritional Therapy Practitioners to support clients in adopting evidence-informed, modifiable dietary and lifestyle changes for Type Two Diabetes.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
- Type 2 diabetes is the most common form of diabetes, accounting for 90-95% of cases.
- Previous randomised trials assessed low carbohydrate diets (LCDs) (<26-45% of daily calories from carbohydrate) as encouraging to improve blood glucose control and outcomes of type 2 diabetes but did not systematically assessed remission of diabetes using low carbohydrate diets (LCDs) and very low carbohydrate diets (VLCDs) for people with type 2 diabetes.
- Systematic reviews (SR) and meta-analyses represent the most valuable, reliable, and objective tool to summarise evidence from primary studies.
- This SR assessed 23 randomised controlled trials comparing LCDs with mostly low fat control diets in individuals / subjects / participants with type 2 diabetes. LCDs were defined as diets with less than 130 g/day or less than 26% of calories from carbohydrates, based on 2000 kcal/day. The authors used the Cochrane Risk of Bias tool 2.0 (RoB 2) to assess methodological quality of evidence, GRADE to assess the certainty of evidence
- On the basis of assessment of moderate to low certainty evidence, individuals / subjects / participants adhering to a LCD for six months may experience remission of type 2 diabetes without adverse consequences.
- Primary outcomes of interest were remission of type 2 diabetes (dichotomously defined as HbA1c <6.5% or fasting glucose <7.0 mmol/L), with or without the use of diabetes medication.
- Eight studies reported on remission of diabetes at six months. Pooled analysis showed that when remission was defined by an HbA1c level below 6.5% independent of medication use, LCDs increased remissions by an additional 32 per 100 patients followed (risk difference 0.32, 95% confidence interval 0.17 to 0.47; 8 studies, n=264; GRADE=moderate)
- When remission was defined by an HbA1c level below 6.5% and the absence of diabetes medication, LCDs increased remissions at a lower rate (risk difference 0.05, –0.05 to 0.14; 5 studies, n=199; GRADE=low)
- Additional primary outcomes were weight loss, HbA1c:
- 18 studies reported on Weight loss results (mean difference –3.46, 95% confidence interval –5.25 to –1.67; n=882 (note that positive results not sustained at 12 mo)
- Seventeen studies reported on HbA1c levels at six months, LCDs achieved greater reductions in HbA1c than did control diets (mean difference –0.47%, –0.60 to –0.34; n=747
- Limitations of study: 1) the definition of remission of diabetes, 2) Self-reported dietary intake data are prone to measurement error, particularly in dietary trials in which participants are not blinded
- This SR was funded in part by Texas A&M University.
- The authors declared no conflicts of interest.
Clinical practice applications:
The Authors highlight LCD diets incorporating carbohydrate of less than 130 g/day or less than 26% of calories (based on 2000 kcal/day) may be a safe strategy to help individuals with type 2 diabetes achieve weight loss and better blood glucose control over a six-month period. Results may not be sustained at 12 months.
Considerations for future research:
- The definition of diabetes remission needs clarification, especially with regard to threshold concentrations of Hb1Ac or fasting glucose and the use of diabetes medication.
- Safety concerns have been raised with LCDs. Although no significant or clinically important increase in total or serious adverse events was identified in this SR, these outcomes should be reported in future trials to confirm the certainty of evidence for safety.
- The Authors suggest long term, well designed, calorie controlled randomised trials are needed to determine the effects of LCD on sustained weight loss and remission of diabetes.
- Larger treatment effects for LCDs in shorter term trials (3 to <6 months), may be trialed as an effect modifier
Abstract
OBJECTIVE To determine the efficacy and safety of low carbohydrate diets (LCDs) and very low carbohydrate diets (VLCDs) for people with type 2 diabetes. DESIGN Systematic review and meta-analysis. DATA SOURCES Searches of CENTRAL, Medline, Embase, CINAHL, CAB, and grey literature sources from inception to 25 August 2020. STUDY SELECTION Randomized clinical trials evaluating LCDs (<130 g/day or <26% of a 2000 kcal/day diet) and VLCDs (<10% calories from carbohydrates) for at least 12 weeks in adults with type 2 diabetes were eligible. DATA EXTRACTION Primary outcomes were remission of diabetes (HbA1c <6.5% or fasting glucose <7.0 mmol/L, with or without the use of diabetes medication), weight loss, HbA1c, fasting glucose, and adverse events. Secondary outcomes included health related quality of life and biochemical laboratory data. All articles and outcomes were independently screened, extracted, and assessed for risk of bias and GRADE certainty of evidence at six and 12 month follow-up. Risk estimates and 95% confidence intervals were calculated using random effects meta-analysis. Outcomes were assessed according to a priori determined minimal important differences to determine clinical importance, and heterogeneity was investigated on the basis of risk of bias and seven a priori subgroups. Any subgroup effects with a statistically significant test of interaction were subjected to a five point credibility checklist. RESULTS Searches identified 14 759 citations yielding 23 trials (1357 participants), and 40.6% of outcomes were judged to be at low risk of bias. At six months, compared with control diets, LCDs achieved higher rates of diabetes remission (defined as HbA1c <6.5%) (76/133 (57%) v 41/131 (31%); risk difference 0.32, 95% confidence interval 0.17 to 0.47; 8 studies, n=264, I2=58%). Conversely, smaller, non-significant effect sizes occurred when a remission definition of HbA1c <6.5% without medication was used. Subgroup assessments determined as meeting credibility criteria indicated that remission with LCDs markedly decreased in studies that included patients using insulin. At 12 months, data on remission were sparse, ranging from a small effect to a trivial increased risk of diabetes. Large clinically important improvements were seen in weight loss, triglycerides, and insulin sensitivity at six months, which diminished at 12 months. On the basis of subgroup assessments deemed credible, VLCDs were less effective than less restrictive LCDs for weight loss at six months. However, this effect was explained by diet adherence. That is, among highly adherent patients on VLCDs, a clinically important reduction in weight was seen compared with studies with less adherent patients on VLCDs. Participants experienced no significant difference in quality of life at six months but did experience clinically important, but not statistically significant, worsening of quality of life and low density lipoprotein cholesterol at 12 months. Otherwise, no significant or clinically important between group differences were found in terms of adverse events or blood lipids at six and 12 months. CONCLUSIONS On the basis of moderate to low certainty evidence, patients adhering to an LCD for six months may experience remission of diabetes without adverse consequences. Limitations include continued debate around what constitutes remission of diabetes, as well as the efficacy, safety, and dietary satisfaction of longer term LCDs. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42020161795.
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Targeting body composition in an older population: do changes in movement behaviours matter? Longitudinal analyses in the PREDIMED-Plus trial.
Galmes-Panades, AM, Konieczna, J, Varela-Mato, V, Abete, I, Babio, N, Fiol, M, Antonio de Paz, J, Casas, R, Olbeyra, R, Ruiz-Canela, M, et al
BMC medicine. 2021;19(1):3
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Expert Review
Conflicts of interest:
None
Take Home Message:
- The importance of including daily physical activity in place of sedentary behaviour.
- The additional benefits of moderate-to vigorous physical activity.
- The importance of seeking medical advice before commencing a physical activity programme
- The importance of working with qualified exercise prescribers when embarking on a new activity programme
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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X
C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction:
Authors highlight that although the relationship between physical activity (PA), sedentary behaviour (SB) and markers of obesity and body composition (BC) have been studied extensively, the balance between PA at different levels of intensity e.g. light physical activity (LPA) intensity and medium to vigorous activity (MVPA) intensity as well as SB in older, obese/overweight adults remains unclear.
Aim and Objectives:
This longitudinal, observational prospective study aimed to explore the relationships between PA and SB in an older population with Metabolic Syndrome (MetS) over a period of 12 weeks (n=1564).
The objectives were specifically to:
1. Evaluate the relationship of concurrent changes in self=reported PA and SB with body composition changes at 12 months using dual-energy X-ray absorptiometry (DEXA).
2. Evaluate the impact of replacing SB with PA at different intensities (LA and MVPA) on BC changes.
Accelerometer-derived inactive time (IT) data was used as a proxy for SB.
Study Design:
The study was nested in the PREDIMED-Plus trial, registered at ISRCTN (89898870). 1564 participants were recruited for the sub-sample (men aged 55-75 n=813; women aged 60-75 n=751) with a BMI >27 and < 40kg/m2 and 3 components of MetS. Data was collected at baseline, 6 and 12 months.
Intervention:
Multicomponent weight loss based on energy restricted Mediterranean Diet (erMedDiet), increasing 30 mins of total PA with behavioural support.
Control:
MedDiet without energy restriction or additional support.
Results:
- At 12 months, participants (intervention and control groups) reduced their waist circumference, BMI, body fat, visceral adipose tissue (VAT) and total energy intake compared to baseline. They increased percentage of muscle mass and muscle-to-fat mass ratio.
- At 6 and 12 months, participants accrued more total PA, LPA and MVPA and less total SB compared to baseline.
After adjustment for potential confounders:
- Increasing 30 min of PA was significantly associated with a decrease in body fat (β − 0.07%, 95% CIs − 0.10; − 0.04%) and VAT (− 13.9 g; − 21.5; − 6.23) and increased muscle mass (0.07%; 0.04; 0.10) and muscle-to-fat mass ratio (0.41; 0.15; 0.67).
- Increasing 30 min of MVPA was linked to significantly reduced body fat (− 0.08%, − 0.11; − 0.04%) and VAT (− 15.6 g; − 24.1; − 7.25) and with increased muscle mass (0.07%; 0.04; 0.10) and muscle-to-fat mass ratio (0.44; 0.15; 0.72).
- Overall, 30 more minutes of total SB was associated with significantly greater body fat and lower muscle mass.
- No significant associations were observed for LPA.
Conclusions:
Increasing PA and substituting SB with PA, in particular MVPA is correlated with improvements in body composition in overweight or obese older adults with MetS.
Clinical practice applications:
- To inform older clients (>55yrs) on the benefits of PA on a range of health conditions e.g. cardiovascular disease and symptoms e.g. metabolic symptoms
- To provide guidance on the benefits of replacing SB with PA, with examples of optimal amount of time and intensity, obviously working within professional boundaries and referring on to relevant experts when necessary
- To encourage practitioners to include recommendations of physical activity as part of a comprehensive approach to physical well-being
Considerations for future research:
- Analyse how increases in physical activity may benefit other chronic health conditions in older adults
- Evaluate how exchanging sedentary behaviour with physical activity may benefit mental health symptoms such as mood and anxiety in adults.
- Explore different facilitators and barriers to increasing physical activity to reduce sedentary behaviour in adults.
Abstract
BACKGROUND The optimal distribution between physical activity (PA) levels and sedentary behaviour (SB) for the greatest benefits for body composition among older adults with overweight/obesity and chronic health conditions remains unclear. We aimed to determine the prospective association between changes in PA and in SB with concurrent changes in body composition and to examine whether reallocating inactive time into different physical activity levels was associated with 12-month change to body composition in older adults. METHODS Longitudinal assessment nested in the PREDIMED-Plus trial. A subsample (n = 1564) of men and women (age 55-75 years) with overweight/obesity and metabolic syndrome from both arms of the PREDIMED-Plus trial was included in the present analysis. Participants were followed up at 6 and 12 months. Physical activity and SB were assessed using validated questionnaires. Out of 1564 participants, 388 wore an accelerometer to objectively measure inactive time and PA over a 7-day period. At each time point, participants' body composition was measured using dual-energy X-ray absorptiometry (DXA). Standard covariate-adjusted and isotemporal substitution modelling were applied to linear mixed-effects models. RESULTS Increasing 30 min of total PA and moderate-to-vigorous physical activity (MVPA) was associated with significant reductions in body fat (β - 0.07% and - 0.08%) and visceral adipose tissue (VAT) (- 13.9 g, and - 15.6 g) at 12 months (all p values < 0.001). Reallocating 30 min of inactive time to MVPA was associated with reductions in body fat and VAT and with an increase in muscle mass and muscle-to-fat mass ratio (all p values < 0.001). CONCLUSIONS At 12 months, increasing total PA and MVPA and reducing total SB and TV-viewing SB were associated with improved body composition in participants with overweight or obesity, and metabolic syndrome. This was also observed when substituting 30 min of inactive time with total PA, LPA and MVPA, with the greatest benefits observed with MVPA. TRIAL REGISTRATION International Standard Randomized Controlled Trial (ISRCTN), 89898870 . Retrospectively registered on 24 July 2014.
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6.
Serum vitamin E levels and chronic inflammatory skin diseases: A systematic review and meta-analysis.
Liu, X, Yang, G, Luo, M, Lan, Q, Shi, X, Deng, H, Wang, N, Xu, X, Zhang, C
PloS one. 2021;16(12):e0261259
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Vitiligo, Psoriasis, Acne and Atopic Dermatitis are chronic immune-mediated inflammatory skin conditions characterised by itchy skin. In previous studies, decreased serum vitamin E levels have been associated with an increased risk of skin diseases. Nuts, oils from plants, and vegetables contain vitamin E, which is a dietary bioactive compound that has anti-inflammatory and antioxidant properties. In this systematic review and meta-analysis, twenty case-controlled studies were included, of which thirteen specifically examined alpha-tocopherol levels. Psoriasis, Vitiligo, atopic dermatitis, and acne patient groups had significantly lower levels of serum Vitamin E than the control groups. There is no clear understanding of the pathogenesis of chronic inflammatory skin conditions. One of the underlying mechanisms is the interaction between oxidative stress and the immune system, as well as the accumulation of free radicals in the epidermal layers of the skin. As there is limited evidence regarding the benefits of Vitamin E in improving chronic inflammatory skin conditions, further robust studies are necessary. Healthcare professionals can use this research to gain a better understanding of the potential clinical applications of vitamin E in the treatment of skin disorders.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Low serum vitamin E levels are reported to be associated with several chronic inflammatory skin diseases, such as vitiligo, psoriasis, atopic dermatitis, and acne.
- Practitioners could consider vitamin E therapy in those with low serum concentrations
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
This systematic review and meta-analysis report on the association between serum vitamin E levels and chronic inflammatory skin diseases.
The review which followed PRISMA reporting guidelines, screened 892 studies. After the selection and exclusions, 20 case-control studies were included involving a total of 1172 patients.
The studies that were included focused mainly on chronic inflammatory diseases, including vitiligo, psoriasis, atopic dermatitis, and acne. Eight studies included only adults, five included only children or teenagers and six studies included adults and children. One study had no age description.
Thirteen studies stated that alpha-tocopherol was used in their investigations. However, seven studies did not describe the subunit of vitamin E.
Primary clinical outcomes were:
- Seven studies, with 351 cases and 350 controls reported that compared with the control group, vitiligo patients had lower serum vitamin E concentrations (Standard Mean Difference (SMD):0.70, 95% Cl:121-0.19.
- Six studies investigated the change of serum vitamin E levels in patients with psoriasis, with 278 cases and 257 controls. Compared with the control group, psoriasis patients had lower serum vitamin E concentrations (SMD: -2.37, 95% CI: -3.57 to -1.18).
- The serum vitamin E Levels in patients with atopic dermatitis were observed in 4 studies, with 259 cases and 307 controls. Compared with the control group atopic dermatitis patients had lower serum vitamin E concentrations (SMD: -1.08, 95% CI: -1.80 to -0.36).
Levels of serum vitamin E in acne patients were reported in 3 studies, with 284 cases and 186 controls. Compared with the control group, acne patients had lower serum concentration levels of vitamin E (SMD: -0.67, 95% CI: -1.05 to -0.30).
No publication bias was found in any association (Egger’s test >0.05), though heterogeneity was considerable in every case (I2 > 80%), though this interaction was not significant for acne (p=0.879). Associations were not split by age, or any other cofactor, however sensitivity analyses did not indicate modification of the results.
The authors also assessed the association between skin disease severity and serum vitamin E concentrations. Overall, more severe disease was associated with a lower serum vitamin E concentration (SMD -1.56, 95% CI:-2.53 to -059).
Clinical practice applications:
- Vitamin E has gained the attention of researchers as a potential adjuvant therapy for various skin disorders due to its excellent antioxidant and anti-inflammatory properties.
- This review reports on the low levels of serum vitamin E found in patients with vitiligo, psoriasis, atopic dermatitis, and acne, and also suggests that serum concentrations of vitamin E are lower in those with more severe disease. Based on these findings, practitioners could therefore consider investigating the serum vitamin E levels of patients with inflammatory skin diseases and consider including vitamin E in their treatment protocols if their serum vitamin E levels are low.
Considerations for future research:
- The small number of studies in this review indicates the need for further research to be done on vitamin E and inflammatory skin diseases.
- Although there are reports on the antioxidant and anti-inflammatory properties of vitamin E, further investigations are needed to determine the exact mechanism of action in inflammatory skin diseases.
- Additionally, further investigation is needed to evaluate which chemical forms of vitamin E and their dosage amounts have beneficial effects on inflammatory skin diseases.
Abstract
BACKGROUND Vitamin E has long been linked to skin health, including all of its possible functions in cosmetic products, to its roles in membrane integrity and even the aging process. However, reports on the relationship between serum vitamin E levels and the risk of chronic inflammatory skin diseases have been inconsistent. We performed a systematic review and meta-analysis to evaluate the association between serum vitamin E levels and chronic inflammatory skin diseases. METHODS We searched the PubMed, Web of Science and Scopus databases, with no time limit up to 30.06.2021. Studies examining serum vitamin E levels in patients with chronic inflammatory skin diseases were selected. RESULTS Twenty articles met the inclusion criteria. Compared with controls, a lower vitamin E level was found in patients with vitiligo (SMD: -0.70, 95% CI: -1.21 to -0.19), psoriasis (SMD: -2.73, 95% CI: -3.57 to -1.18), atopic dermatitis (SMD: -1.08, 95% CI: -1.80 to -0.36) and acne (SMD: -0.67, 95% CI: -1.05 to -0.30). CONCLUSIONS Our meta-analysis showed that serum vitamin E levels were lower in patients suffering from vitiligo, psoriasis, atopic dermatitis and acne. This study highlights the need to evaluate vitamin E status to improve its level in patients with skin diseases.
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7.
Effect of sleep duration on dietary intake, desire to eat, measures of food intake and metabolic hormones: A systematic review of clinical trials.
Soltanieh, S, Solgi, S, Ansari, M, Santos, HO, Abbasi, B
Clinical nutrition ESPEN. 2021;45:55-65
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Plain language summary
Adequate sleep is crucial to health. Yet, sleep disturbances have become very common in modern societies. A lack of sleep is linked to increased risk for several chronic diseases such as diabetes, high blood pressure, metabolic syndrome and cardiovascular disease. Furthermore, appetite-regulating hormones can be disrupted by sleep shortages, which is thought to drive chronic overeating, leading to weight gain, obesity and its associated health consequences. This review examined the relationship between sleep duration and food consumption and energy intake, whilst also monitoring changes in body weight and appetite-regulating hormones. The review encompassed 50 randomized controlled trials (RCTs) with 3387 participants, including 1079 children and adolescents and 2308 adults. The findings suggested that sleep shortages contribute to significant increases in calorie intake, fat intake, increased body weight, appetite, hunger, more frequent eating and bigger portion sizes. In this review lack of sleep did not change protein and carbohydrate intake. Nor did lack of sleep make people exert more or less energy overall, however, a variance amongst ethnic groups was observed here. There was not enough evidence for changes in metabolic rate, so the review assumed no significant effect. When viewed collectively, the appetite-regulating hormones of leptin and ghrelin, the stress hormone cortisol and the sugar-regulating hormone insulin were not significantly influenced by sleep duration. However, there seemed to be a wide variance of outcomes when looking at individual studies' results. In conclusion, the authors reiterated the importance of sleep for health maintenance, advocating for a minimum of 7 hours of sleep per day for adults and that, despite busy modern lifestyles, sleep optimisation strategies should be prioritised. Less than 6 hours of sleep per day increases the risk of health consequences, like weight gain and metabolic disorders and sleep management should be considered part of their treatment protocols.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Reduced sleep duration may serve as a mediator for weight gain in part due to increased appetite, increased fat intake and disruptions to energy balance.
- Enhancing sleep quality may serve to support weight loss protocols.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
Short sleep duration and disruptions to circadian rhythm have been associated with being overweight and obese. It has been suggested that sleep restriction may interfere with appetite regulating hormones leading to increased appetite and disrupted energy balance.
This study aimed to systematically review studies exploring the relationship between sleep duration and food consumption, energy intake, anthropometric characteristics and appetite-regulating hormones.
Methods
This systematic review included 50 randomised controlled trials including 3,387 participants.
Results
Energy intake
- 13 out of 30 the included studies found that short sleep conditions led to higher energy intake.
- 1 study identified that sleep restriction resulted in a 15.3% and 9.2% increase in energy intake in both women and men.
- 3 studies noted that prolonging sleep duration led to a reduction in energy intake.
- 1 study reported a reduction in energy intake after sleep restriction (P=0.031).
Fat consumption
- 9 studies out of 22 identified a significant association between short sleep and increased fat consumption.
- 7 studies did not identify a difference between groups.
- 3 studies noted a decrease in fat consumption following prolonged sleep (P<0.001, P<0.05, P=0.04).
Hunger and appetite
- 11 studies out of 17 observed that sleep restriction resulted in increased hunger ratings.
- 3 studies found an increase in appetite following sleep restriction (P<0.01) with 3 finding no difference..
- 1 study reported a decrease in appetite following sleep restriction.
- 2 studies noted that portion sizes increased as a result of sleep restriction (P<0.01).
- 1 study reported an increase in eating occasions following restricted sleep compared to habitual sleep (6.08 vs 4.96).
Body weight
- 6 studies out of 14 found no effect of sleep loss on body weight.
- 4 studies identified that sleep restriction led to weight gain (P<0.001, P<0.05, P=0.14, P=0.031).
- 2 studies reported weight loss following increased sleep duration (P<0.001).
Ghrelin and leptin
- Leptin and ghrelin levels were generally not found to be influenced by sleep duration, with the exception of a few studies.
Clinical practice applications:
Reduced sleep duration may promote weight gain by:
- Increasing energy intake.
- Increasing fat consumption.
- Increasing hunger and appetite.
- Increasing portion sizes and eating occasions.
Prolonging sleep duration may support weight loss by:
- Reducing energy intake.
- Reducing fat intake.
Considerations for future research:
- Mixed results on the influence of sleep restriction on appetite regulating hormones, leptin and ghrelin.
- Some studies noted the negative impact of sleep restriction on leptin and ghrelin concentrations, collectively shortened sleep duration did not appear to influence these hormones.
- Further sleep restriction studies exploring additional appetite regulating hormones and neuropeptides and the reward system may provide a more definitive understanding of the underlying mechanism for reduced sleep duration to disrupt the appetite and energy balance and promote weight gain.
Abstract
BACKGROUND AND AIMS Sleep, as well as diet and physical activity, plays a significant role in growth, maturation, health, and regulation of energy homeostasis. Recently, there is increasing evidence indicating a possible causal association between sleep duration and energy balance. We aimed to examine the relationship between sleep duration and food consumption, energy intake, anthropometric characteristics, and appetite-regulating hormones by randomized controlled trials (RCTs). METHODS Electronic literature searches were conducted on Medline, Web of Science, and Google Scholar until July 2020. The search was conducted with the following words: "Sleep Duration", "Circadian Rhythm", "Sleep Disorders" in combination with "Obesity", "Overweight", "Abdominal Obesity", "Physical Activity", "Energy Intake", "Body Mass Index", "Lipid Metabolism", "Caloric Restriction", Leptin, "Weight Gain", and "Appetite Regulation" using human studies.methods RESULTS After screening 708 abstracts, 50 RCTs (7 on children or adolescents and 43 on adults) were identified and met the inclusion criteria. In general, the findings suggested that sleep restriction may leads to a significant increment in energy intake, fat intake, body weight, appetite, hunger, eating occasions, and portion size, while protein and carbohydrate consumption, total energy expenditure, and respiratory quotient remained unaffected as a result of sleep restriction. Serum leptin, ghrelin, and cortisol concentrations were not influenced by sleep duration as well. CONCLUSION Insufficient sleep can be considered as a contributing factor for energy imbalance, weight gain, and metabolic disorders and it is suggested that to tackle disordered eating it may be necessary to pay more attention to sleep duration.
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8.
The burden of disease of three food-associated heavy metals in clusters in the Danish population - Towards targeted public health strategies.
Herrera, JAR, Thomsen, ST, Jakobsen, LS, Fagt, S, Banasik, K, Izarzugaza, JM, Brunak, S, Pires, SM
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association. 2021;150:112072
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Expert Review
Conflicts of interest:
None
Take Home Message:
- The burden of disease from methylmercury, cadmium and inorganic arsenic exposure in some Danish subpopulations with certain dietary and lifestyle patterns and sociodemographics may be increased.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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X
E: Opinion piece, other
Summary Review:
Introduction
The authors state that lifestyle and sociodemographics might impact dietary patterns, and consequently, human exposure to chemical hazards in foods, and correlated human health effects. The objective was to classify Danish population cohorts into clusters via dietary, lifestyle and sociodemographic indicators, and determine which had an increased disease burden due to methylmercury (MeHg), cadmium (Cd), and inorganic arsenic (iAs) exposure.
Methods
This study involved cluster analysis and chemical risk assessment. Secondary analysis of a cohort study was conducted via collating dietary and lifestyle patterns from Danish national survey data. The extracted dataset included 3946 participants, 80 food groups, and four lifestyle and demographic variables. Metal concentration data were derived from Danish food surveillance data. Population clusters classified subjects with similar dietary and lifestyle patterns, using self-organising maps (SOMs). Dietary exposure to MeHg, Cd and iAs in each cluster was conducted via risk assessment. Furthermore, disease burden was estimated in disability-adjusted life years (DALYs), using 2-D Monte Carlo simulation to account for uncertainty from variability.
Results
SOMs rendered 12 population clusters with distinct features. Human exposure to the metals differed between clusters, primarily driven by fish, seafood, and cereal consumption. A high proportion of females of childbearing age, 33-41 years, respectively, were in the two highest ranking disease burden clusters due to HeMg (i.e, clusters 5 and 6). Five clusters yielded an estimated burden >20 DALYs per 100,000 population per annum.
The highest estimated disease burdens for each metal (mainly urban dwellers) were as follows:
- . MeHg exposure: cluster 6 (highest overall burden); 47.30 DALYs/100,000, 54% female, 41 years (mean age), 74kg (mean body weight), 89% non-smokers, 59% further education, 95% moderate-very high physical activity level;
- iAs exposure: cluster 1, 10.7 DALYs/100,000, 49% female, 8 years old, 31kg, 89% non-smokers, 61% further education, 92% moderate-very high physical activity level;
- Cd exposure: cluster 8, 0.15 DALYs/100,000, 49% female, 59 years, 77kg, 84% non-smokers, 28% further education, 94% moderate-very high physical activity level.
Conclusion
Certain Danish subpopulations held a greater disease burden due to MeHg, Cd and iAs dietary exposure. MeHg bore the highest burden. Clusters of highly educated, urban dwelling, females with seemingly healthy dietary patterns and moderate to high physical activity had the highest burden due to metal exposure. MeHg exposure in women of childbearing age substantially contributed to the total disease burden due to the risk of adverse effects on the foetus.
Clinical practice applications:
- Practitioners and clients need to be informed of the risks of human exposure to methylmercury, cadmium and inorganic arsenic through dietary and lifestyle patterns and sociodemographics, particularly in certain subpopulations.
- Practitioners should educate themselves and their clients regarding the foods which may pose a higher risk to these metals, namely fish, seafood and cereal as cited by the authors.
- The results of the study may contribute to public health and food safety strategies aimed at the most affected cohorts exposed to these chemical contaminants.
Considerations for future research:
- Future studies could investigate other metals and chemical hazards.
- Continuous surveillance of dietary and lifestyle exposure from multiple heavy metals and other chemical contaminants should be prioritised to inform public health and food safety.
- Dietary and lifestyle habit interventions could assess the possibility to reduce the risk of methylmercury, cadmium, inorganic arsenic exposure, and exposure from other metals.
Abstract
Lifestyle and sociodemographics are likely to influence dietary patterns, and, as a result, human exposure to chemical contaminants in foods and their associated health impact. We aimed to characterize subgroups of the Danish population based on diet and sociodemographic indicators, and identify those bearing a higher disease burden due to exposure to methylmercury (MeHg), cadmium (Cd) and inorganic arsenic (i-As). We collected dietary, lifestyle, and sociodemographic data on the occurrence of chemical contaminants in foods from Danish surveys. We grouped participants according to similarities in diet, lifestyle, and sociodemographics using Self-Organizing Maps (SOM), and estimated disease burden in disability-adjusted life years (DALY). SOM clustering resulted in 12 population groups with distinct characteristics. Exposure to contaminants varied between clusters and was largely driven by intake of fish, seafood and cereal products. Five clusters had an estimated annual burden >20 DALY/100,000. The cluster with the highest burden had a high proportion of women of childbearing age, with most of the burden attributed to MeHg. Individuals belonging to the top three clusters had higher education and physical activity, were mainly non-smokers and lived in urban areas. Our findings may facilitate the development of preventive strategies targeted to the most affected subgroups.
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9.
The Window Matters: A Systematic Review of Time Restricted Eating Strategies in Relation to Cortisol and Melatonin Secretion.
Chawla, S, Beretoulis, S, Deere, A, Radenkovic, D
Nutrients. 2021;13(8)
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Plain language summary
Time-Restricted Eating (TRE) is an eating pattern based on the circadian rhythm that gives the body a daily fasting period. This involves limiting daily food intake to 8–12 hours with an intention to prolong the time spent in a fasting state. In fact, chrono-nutrition is an emerging field of nutritional science that aims to understand how timing of food-intake may impact our health by affecting our circadian rhythm. The aim of this study was to examine the effects of two patterns of TRE, traditional TRE (a predetermined window of eating and fasting) and Ramadan fasting, on two markers of circadian rhythm, cortisol and melatonin. This study was a systematic review and meta-analysis of fourteen studies (13 reported results on cortisol, and four on melatonin). Results showed that: - Ramadan practice of TRE resulted in a reduced waking response of cortisol, and in most cases a statistically significant increase relative to non-Ramadan in the evening. - the Ramadan studies also found significant reductions in levels of nocturnal melatonin during Ramadan compared to baseline. - in the non-Ramadan TRE studies, skipping dinner led to a decreased evening cortisol level, and, potentially, an elevated morning level (however not in all cases waking time was accounted for). - skipping breakfast led to a relative increase in midday cortisol. Authors conclude that their findings indicated a potential blunting of the circadian cortisol rhythm during Ramadan and a reduction in melatonin which could lead to poor sleep duration and quality.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Other human and animal studies have highlighted the benefits of restricting the feeding window for longevity and metabolic health.
- Whether one chooses early or late TRE may help to determine the optimal time of alertness and sleep.
- Early TRE, which involves skipping dinner, may allow for greater alertness in the morning as the lower levels of cortisol at night can improve sleep quality and higher morning cortisol raises alertness, optimising wakefulness and productivity.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction:
This systematic review aimed to examine the effects of two patterns of Time Restricted Feeding (TRE): (1) traditional TRE, and (2) Ramadan fasting, on two markers of circadian rhythm: (1) cortisol and (2) melatonin.
Methods
- A search was performed on PubMed, and Web of Science (all databases) up to December 2020 using search terms relating to “time-restricted eating”, “intermittent fasting”, “cortisol”, “melatonin”, and “orexin”.
- 14 randomised controlled trials and observational studies that met the criteria were included.
- Quality assessment of all studies was performed
Results
14 studies met the inclusion criteria. 10 of the studies used TRE in the context of Ramadan (total n=242) whilst 4 followed non-Ramadan TRE protocols (total n=124). Of the 14 studies identified in the literature review, 13 reported results on cortisol, and 4 on melatonin.
- All 4 melatonin studies found a statistically significant reduction of melatonin (p < 0.05) during Ramadan.
- 2 of 3 studies assessing 24-h serum cortisol changes during Ramadan noted an “abolishing” of the circadian rhythm of cortisol (p < 0.05), meaning there was a flattening of cortisol levels during the fasting month compared with the non-fasting month.
- All 13 cortisol studies recorded a cortisol shift in response to time restricted eating, albeit over different time frames and different cortisol recording methods.
- 1 randomised 4-day crossover study (n=11) found skipping dinner resulted in significantly reduced evening cortisol (p=0.03) and non-significantly raised morning cortisol. Skipping breakfast resulted in significantly reduced morning cortisol (p=0.10) .
- 1 observational study of females aged 18-45 (n-65) found that skipping breakfast demonstrated decreased morning (waking) cortisol, elevated midday cortisol, and no significant evening cortisol differences compared to the control group.
Conclusion
The potential blunting of the circadian cortisol rhythm during Ramadan may impact the HPA axis and is associated with poor cardio-metabolic outcomes. A reduction in melatonin could lead to poor sleep duration and quality.
Clinical practice applications:
- The mechanisms behind these findings are not well understood, but are likely to include: the complex endocrine interplay with insulin response and glucocorticoid secretion.
- Caution must be taken in terms of generalisability due to the small sample size of the included studies
Early or late TRE can determine the optimal time of alertness and sleep:
- Early TRE (eating 8am-2pm / skipping dinner), may allow for greater alertness in the morning as the lower levels of cortisol at night can improve sleep quality and higher morning cortisol raises alertness, optimising wakefulness and productivity.
- Late TRE (skipping breakfast) may provide greater alertness mid-day, due to an intensified cortisol response mid-day.
Considerations for future research:
In order to better understand the effects of meal timing on health outcomes, further larger studies should be conducted. They should:
- Examine TRE during the inactive and active phases of the circadian rhythm under controlled conditions.
- Exclude studies relating to pregnancy, pathology, and athletic status.
- Ensure sufficient control for confounding factors that can affect serum parameters, including sleep duration and timing, total energy expenditure, and light exposure
Abstract
Time-Restricted Eating is an eating pattern based on the circadian rhythm which limits daily food intake (usually to ≤12 h/day), unique in that no overt restriction is imposed on the quality, nor quantity, of food intake. This paper aimed to examine the effects of two patterns of TRE, traditional TRE, and Ramadan fasting, on two markers of circadian rhythm, cortisol and melatonin. PubMed and Web of Science were searched up to December 2020 for studies examining the effects of time restricted eating on cortisol and melatonin. Fourteen studies met our inclusion criteria. All Ramadan papers found statistically significant decrease in melatonin (p < 0.05) during Ramadan. Two out of the three Ramadan papers noted an abolishing of the circadian rhythm of cortisol (p < 0.05). The non-Ramadan TRE papers did not examine melatonin, and cortisol changes were mixed. In studies comparing TRE to control diets, Stratton et al. found increased cortisol levels in the non-TRE fasting group (p = 0.0018) and McAllister et al. noted no difference. Dinner-skipping resulted in significantly reduced evening cortisol and non-significantly raised morning cortisol. Conversely, breakfast skipping resulted in significantly reduced morning cortisol. This blunting indicates a dysfunctional HPA axis, and may be associated with poor cardio-metabolic outcomes. There is a paucity of research examining the effects of TRE on cortisol and melatonin. The contrasting effect of dinner and breakfast-skipping should be further examined to ascertain whether timing the feeding window indeed has an impact on circadian rhythmicity.
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10.
Effect of selenium on thyroid autoimmunity and regulatory T cells in patients with Hashimoto's thyroiditis: A prospective randomized-controlled trial.
Hu, Y, Feng, W, Chen, H, Shi, H, Jiang, L, Zheng, X, Liu, X, Zhang, W, Ge, Y, Liu, Y, et al
Clinical and translational science. 2021;14(4):1390-1402
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Plain language summary
Hashimoto thyroiditis (HT) is the most common thyroid autoimmune disease. Multiple factors contribute to the development of the disease leading to immune system-mediated destruction of the thyroid gland. In the absence of specific therapeutic approaches that address the immunological activity, thyroid hormone replacement is the primary treatment. Selenium (Se) is an essential trace element for humans and the thyroid gland utilises high amounts of selenium for the production of enzymes and antioxidants. Supplementing Se has shown positive effects in HT, as demonstrated in some studies. Yet, there have been inconsistencies in the results and the understanding of the mechanisms involved are limited. The authors of this prospective, randomized controlled study tried to shed some light on the efficacy of Se supplementation and its mechanisms. 43 HT-patients on no thyroid medication, received 200mcg Se per day for 6 months. Various markers were assessed including antibodies, thyroid stimulating hormone (TSH), antioxidant enzymes and T-helper immune cells that regulate immunological activity, which were compared to the HT-control group (n=47) and healthy individuals (n=36). The outcome of the intervention showed that Se supplementation can reduce thyroid antibodies, and TSH and can increase antioxidant enzymes in patients with HT and along with the findings the authors discussed some potential mechanisms at play. This study suggests that supplementary Se can benefit HT, particularly subclinical HT.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Selenium supplementation is reported to reduce TPOAb, TGAb, and TSH levels, as well as increase Se, GPx3, and SePP1 concentrations in patients with HT without the use of levothyroxine replacement.
- Practitioners could consider selenium supplementation in patients with HT who have serum selenium levels less than 120ug/L.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
A prospective randomised controlled trial was conducted to investigate the effect of selenium (Se) supplementation in patients with Hashimoto’s thyroiditis (HT). The study also explored the potential mechanisms of action of Selenium in thyroid autoimmunity.
One hundred and twenty-six subjects (90 with HT and 36 healthy individuals) were included in the study. The patients with HT were randomly assigned into two groups. The Se-treated group (n=43) received 200ug of selenium in a selenious yeast tablet (SYT) per day for 6 months. No treatment was given to the control group (n=47). At the endpoint, 126/126 subjects completed the study.
Primary clinical outcomes were:
- Antithyroid peroxidase antibodies (TPOAb) levels were significantly lower compared with the control group at 6 months (ΔTPOAb [IU/ml] = −28.4 [−103.9,0] vs. 0 [−18.1, 20.5], p = 0.001).
- There was a significant difference in antithyroglobulin antibodies TGAb titers between the Se-treated group and the control group at 6 months (ΔTGAb [IU/ml] = −48.8 [−139.7, −2.0] vs. 18.3 [−23.5, 77.4], p = 0.001.
- Compared with baseline, thyroid stimulating hormone (TSH) presented slightly lower levels in the Se-treated group, whereas there was a statistical increase in the control group at 6 months (ΔTSH [mIU/L] = −0.16 [−2.1, 0.28] vs. 0.48 [−0.15, 1.47], p = 0.001).
Secondary clinical outcomes were:
- aTreg cells in the Se-treated group were significantly higher than the control group at 6 months (13.19 ± 3.5 vs. 11.49 ± 2.79, p = 0.012)
- There was a pronounced increase in glutathione peroxidase (GPx3) at 6 months of treatment in the Se-treated group compared with the control group (p=0.028).
- Furthermore, Selenoprotein P1 (SePP1) levels increased in the Se-treated group compared with the control group at 6 months (17.2 [9.8, 22.1] vs. 10.7 [8.9, 14.6], p = 0.007).
Clinical practice applications:
- There is no specific approach to suppress autoimmunity, thus thyroxine replacement has become the generally accepted therapy for patients with Hashimoto’s thyroiditis (HT) with hypothyroidism.
- The thyroid gland contains the highest concentration of selenium, which is incorporated into selenoproteins, such as glutathione peroxidase (GPx), selenoprotein P (SePP), thioredoxin reductase, and iodothyronine deiodinases. These selenoenzymes play important roles in thyroid hormone metabolism by acting as antioxidants and immunomodulators.
- Based on this study, practitioners could therefore consider using 200ug of selenium for six months as a supportive measure specifically in patients with serum selenium levels less than 120ug/L.
Considerations for future research:
- Although about 20 studies have investigated the treatment of selenium in HT further research is warranted to help explore the appropriate use of selenium.
- Furthermore, investigations are needed to establish if certain HT patients could benefit more from Se supplementation.
- Additionally, investigations are needed to understand the relationship between selenium and Treg cells and their impact on thyroid antibodies.
- This study was completed over six months, longer studies are required to investigate the effect of selenium supplementation over the clinical course of HT.
Abstract
Selenium (Se) is an essential trace element in human. Recent studies of Se supplementation on the effect of Hashimoto's thyroiditis (HT) have been reported, but the exact benefit is unclear as well as the underlying immunologic mechanism. We aimed to evaluate the clinical effect of Se supplement in patients with HT, and explore the potential mechanism against thyroid autoimmunity. A prospective, randomized-controlled study was performed in patients with HT assigned to two groups. Se-treated group (n = 43) received selenious yeast tablet (SYT) for 6 months, whereas no treatment in control group (n = 47). The primary outcome is the change of thyroid peroxidase antibody (TPOAb) or thyroglobulin antibody (TGAb). Second, thyroid function, urinary iodine, Se, Glutathione peroxidase3 (GPx3), and Selenoprotein P1 (SePP1) levels were measured during the SYT treatment. Meanwhile, regulatory T cells (Tregs) and their subsets activated Tregs (aTregs), resting Tregs, and secreting Tregs, as well as Helios and PD-1 expression on these cells were also detected. The results showed that SYT treatment significantly decreased TPOAb, TGAb, and thyroid stimulating hormone (TSH) levels, accompanied with the increased Se, GPx3, and SePP1, compared with the control group. Subgroup analysis revealed that subclinical HT may benefit more from this treatment in the decrease of TSH levels by interaction test. Moreover, the percentage of aTregs, Helios/Tregs, and Helios/aTregs were significantly higher in the Se-treated group than control. In conclusion, Se supplementation may have a beneficial effect on thyroid autoantibodies and thyroid function by increasing the antioxidant activity and upregulating the activated Treg cells.