-
1.
Nuts and seeds consumption and risk of cardiovascular disease, type 2 diabetes and their risk factors: a systematic review and meta-analysis.
Arnesen, EK, Thorisdottir, B, Bärebring, L, Söderlund, F, Nwaru, BI, Spielau, U, Dierkes, J, Ramel, A, Lamberg-Allardt, C, Åkesson, A
Food & nutrition research. 2023;67
-
-
-
Free full text
Plain language summary
Nuts and seeds consumption is associated with a reduced risk of coronary heart disease (CHD) and cardiovascular disease (CVD). Nuts and seeds contain beneficial components to reduce the risk of CVD and CHD; hence dietary addition may benefit heart health. This systematic review and meta-analysis included sixty studies to analyse the effects of the consumption of nuts and seeds on the incidence of mortality from type 2 diabetes (T2D) and CVD and intermediate cardiometabolic risk factors. High nuts and seed consumption showed a 19% reduction in CVD risk and a 23% reduction in CVD mortality. In addition, high consumption lowered the risk of CHD by 25%. Increased nut consumption up to 30 g/day showed a dose-dependent relationship with reduced risk of CVD. Healthcare professionals can use the results of this study to understand the association between nuts and seeds consumption and CHD, CVD and blood lipid levels. However, further robust studies are required to evaluate the effect of specific nuts and seeds on CHD and CVD risk reduction.
Abstract
OBJECTIVES We aimed to systematically review studies and evaluate the strength of the evidence on nuts/seeds consumption and cardiometabolic diseases and their risk factors among adults. METHODS A protocol was pre-registered in PROSPERO (CRD42021270554). We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials and Scopus up to September 20, 2021 for prospective cohort studies and ≥12-week randomized controlled trials (RCTs). Main outcomes were cardiovascular disease (CVD), coronary heart disease (CHD), stroke and type 2 diabetes (T2D), secondary total-/low density lipoprotein (LDL)-cholesterol, blood pressure and glycaemic markers. Data extraction and risk of bias (RoB) assessments (using RoB 2.0 and RoB-NObS) were performed in duplicate. Effect sizes were pooled using random-effects meta-analyses and expressed as relative risk (RR) or weighted mean differences with 95% confidence intervals (CI); heterogeneity quantified as I 2. One-stage dose-response analyses assessed the linear and non-linear associations with CVD, CHD, stroke and T2D. The strength of evidence was classified per the World Cancer Research Fund criteria. RESULTS After screening 23,244 references, we included 42 papers from cohort studies (28 unique cohorts, 1,890,573 participants) and 18 RCTs (2,266 participants). In the cohorts, mainly populations with low consumption, high versus low total nuts/seeds consumption was inversely associated with total CVD (RR 0.81; 95% CI 0.75, 0.86; I 2 = 67%), CVD mortality (0.77; 0.72, 0.82; I 2 = 59.3%), CHD (0.82; 0.76, 0.89; I 2 = 64%), CHD mortality (0.75; 0.65, 0.87; I 2 = 66.9%) and non-fatal CHD (0.85; 0.75, 0.96; I 2 = 62.2%). According to the non-linear dose-response analyses, consumption of 30 g/day of total nuts/seeds was associated with RRs of similar magnitude. For stroke and T2D the summary RR for high versus low intake was 0.91 (95% CI 0.85, 0.97; I 2 = 24.8%) and 0.95 (0.75, 1.21; I 2 = 82.2%). Intake of nuts (median ~50 g/day) lowered total (-0.15 mmol/L; -0.22, -0.08; I 2 = 31.2%) and LDL-cholesterol (-0.13 mmol/L; -0.21, -0.05; I 2 = 68.6%), but not blood pressure. Findings on fasting glucose, HbA1c and insulin resistance were conflicting. The results were robust to sensitivity and subgroup analyses. We rated the associations between nuts/seeds and both CVD and CHD as probable. There was limited but suggestive evidence for no association with stroke. No conclusion could be made for T2D. CONCLUSION There is a probable relationship between consumption of nuts/seeds and lower risk of CVD, mostly driven by CHD, possibly in part through effects on blood lipids. More research on stroke and T2D may affect the conclusions. The evidence of specific nuts should be further investigated.
-
2.
Comparative effects of vitamin and mineral supplements in the management of type 2 diabetes in primary care: A systematic review and network meta-analysis of randomized controlled trials.
Xia, J, Yu, J, Xu, H, Zhou, Y, Li, H, Yin, S, Xu, D, Wang, Y, Xia, H, Liao, W, et al
Pharmacological research. 2023;188:106647
-
-
-
-
Free full text
-
Plain language summary
Type 2 diabetes mellitus (T2DM), characterised by sustained hyperglycaemia and insulin resistance, remains a severe driver of chronic metabolic diseases such as cardiovascular diseases. The aim of this study was to investigate and compare the efficacy of vitamin and mineral supplements in the management of glycaemic control and lipid metabolism for type 2 diabetic patients to inform clinical practice. This study is a systematic review and meta-analysis of one hundred and seventy articles with a total of 4223 adults with T2DM. Participants were randomised to either the placebo/no treatment group (n= 6345) or to the treatment group (n= 7878). Results show that: - chromium was the most effective micronutrient for decreasing fasting blood glucose and insulin resistance. - vitamin K was the top-ranked micronutrient in reducing haemoglobin A1C and fasting insulin levels. - vanadium was the top-ranked micronutrient in total cholesterol reductions. - niacin was ranked as the most effective in triglycerides reductions and increasing high-density lipoprotein cholesterol levels. - vitamin E was the top-ranked micronutrient in low-density lipoprotein cholesterol reductions. Authors conclude that micronutrient supplements especially chromium, vitamin E, vitamin K, vanadium, and niacin supplements, may be more effective in the management of T2DM compared with other micronutrients.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Clinicians could consider the adjunctive effect of micronutrients supplements, such as chromium, vitamin E, vitamin K, vanadium, and niacin supplements in a nutrition protocol to manage T2DM and slow or prevent its complications.
- The study authors state that the vitamin and mineral supplements under review had a statistically significant improvement, however they did not reach the study threshold for clinical significance. Therefore they advise caution in utilising micronutrient supplements in the management of glucose and lipid metabolism for T2DM.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Objectives
The aim of this systematic review was to evaluate the comparative effects of vitamin and mineral supplements on managing glycemic control and lipid metabolism for type 2 diabetes mellitus (T2DM).
Methodology
This systematic review is registered with PROSPERO and adhered to PRISMA-2020 guidelines for network meta-analysis
The Cochrane Collaboration’s risk-of-bias tool was used to assess eligible randomised trials
8 prespecified markers identified and assessed in this study : 1) HbA1c (%), 2) fasting blood glucose (mmol/L), 3) total cholesterol (mmol/L), 4) triglycerides (mmol/L), 5) fasting insulin (μIU/mL), 6) HOMA-IR, 7) LDL-c (mmol/L), and 8) HDL-c (mmol/L).
Results
- 170 RCT trials of 14223 participants with T2DM treated with vitamin supplements, mineral supplements, or placebo/no treatment were included
- Low to very low certainty evidence established chromium supplements as the most effective in reducing fasting blood glucose levels and homeostasis model assessment of insulin resistance (SUCRAs: 90.4% and 78.3%, respectively)
- Vitamin K supplements ranked best in reducing glycated haemoglobin A1c and fasting insulin levels (SUCRAs: 97.0% and 82.3%, respectively), with moderate to very low certainty evidence
- Vanadium supplements ranked best in lowering total cholesterol levels with very low evidence certainty (SUCRAs:100%)
- Niacin supplements ranked best in triglyceride reductions and increasing high-density lipo-protein cholesterol levels with low to very low evidence certainty (SUCRAs:93.7% and 94.6%, respectively)
- Vitamin E supplements ranked best in reducing low-density lipoprotein cholesterol levels with very low evidence certainty (SUCRAs:80.0%).
Conclusion
- Micronutrient supplements, such as chromium, vitamin E, vitamin K, vanadium, and niacin supplements, may be efficacious in managing T2DM
- It should be noted that the evidence certainty for all was low.
Clinical practice applications:
- Chromium plays an important role in carbohydrate and lipid metabolism and was the most effective micronutrient for decreasing fasting blood glucose, HbA1c, fasting insulin, and HOMA-IR reductions. More pronounced effects were seen for chromium than vitamin E, vitamin C, niacin, selenium, and magnesium supplements
- Vitamin K was the top-ranked micronutrient in reducing HbA1c and fasting insulin levels. The mechanism through which Vitamin K affects glucose metabolism is proposed as activation of the AMP-activated protein kinase/sirtuin 1, that in turn increases phosphocreatine 3-kinase and glucose transporter 2 to decrease insulin resistance and fasting glucose.
- Vanadium was the top-ranked micronutrient in total cholesterol (TC) reductions, where supplementation dosage should be carefully considered, as vanadium compounds can be moderately or highly toxic. Vanadium supplementation is only recommended in cases of vanadium deficiency or diabetes, hyperlipidemia, and hypertension, where the intake of vanadium from food should be enhanced in preference to supplementation
- Niacin was ranked as the most effective in triglyceride (TG) reductions and increasing HDL cholesterol levels. The dose of niacin could not be determined
- Vitamin E was the top-ranked micronutrient in low-density lipo- protein (LDL) cholesterol reductions.
Considerations for future research:
- Considering the clinical importance of these findings, new research is needed to get better insight into the efficacy of micronutrient supplements in managing T2DM
- Selenium homeostasis, selenoprotein, insulin signaling/secretion, and carbohydrate/lipid metabolism are linked in multiple and complex ways but the authors could not explain why chromium supplementation would lower blood glucose more effectively than selenium supplementation, and suggest more research is needed to clarify this
- While vitamin K status could be an emerging treatment target in T2DM prevention and management, it remains to be determined whether vitamin K supplementation has an advantage over other nutrients in terms of hypoglycemic effect, and further research is necessary
- The beneficial effect of vitamin E and niacin supplements regarding lipid metabolism warrant investigation through more rigorous comparative studies.
Abstract
Medical nutrition treatment can manage diabetes and slow or prevent its complications. The comparative effects of micronutrient supplements, however, have not yet been well established. We aimed at evaluating the comparative effects of vitamin and mineral supplements on managing glycemic control and lipid metabolism for type 2 diabetes mellitus (T2DM) to inform clinical practice. Electronic and hand searches for randomized controlled trials (RCTs) were performed until June 1, 2022. We selected RCTs enrolling patients with T2DM who were treated with vitamin supplements, mineral supplements, or placebo/no treatment. Data were pooled via frequentist random-effects network meta-analyses. A total of 170 eligible trials and 14223 participants were included. Low to very low certainty evidence established chromium supplements as the most effective in reducing fasting blood glucose levels and homeostasis model assessment of insulin resistance (SUCRAs: 90.4% and 78.3%, respectively). Vitamin K supplements ranked best in reducing glycated hemoglobin A1c and fasting insulin levels (SUCRAs: 97.0% and 82.3%, respectively), with moderate to very low certainty evidence. Vanadium supplements ranked best in lowering total cholesterol levels with very low evidence certainty (SUCRAs:100%). Niacin supplements ranked best in triglyceride reductions and increasing high-density lipoprotein cholesterol levels with low to very low evidence certainty (SUCRAs:93.7% and 94.6%, respectively). Vitamin E supplements ranked best in reducing low-density lipoprotein cholesterol levels with very low evidence certainty (SUCRAs:80.0%). Our analyses indicated that micronutrient supplements, especially chromium, vitamin E, vitamin K, vanadium, and niacin supplements, may be more efficacious in managing T2DM than other micronutrients. Considering the clinical importance of these findings, new research is needed to get better insight into this issue.
-
3.
Is Extra Virgin Olive Oil the Critical Ingredient Driving the Health Benefits of a Mediterranean Diet? A Narrative Review.
Flynn, MM, Tierney, A, Itsiopoulos, C
Nutrients. 2023;15(13)
-
-
-
Free full text
Plain language summary
Cardiovascular diseases (CVDs) are the largest contributor to deaths globally, followed by cancers, chronic respiratory diseases and diabetes. It is estimated that 90% of deaths from CVD can be prevented with modifiable risk factors such as diet. The Mediterranean diet, which is rich in extra virgin olive oil (EVOO), is important in the prevention of chronic diseases. There is however very little focus on differentiating healthy fats such as EVOO from other fats and oils in dietary guidelines. This review of 34 studies aims to compare the effect of diets that include EVOO on cardiometabolic risk factors for heart disease, metabolic syndrome, and type 2 diabetes. It looks at the effects on blood pressure (SBP), low- and high-density lipoprotein cholesterol, (HDP-c and LDD-c) fasting blood glucose (FBG) and body weight. It also assesses from published studies the minimum daily amount of EVOO and the shortest time needed to see improvements in the risk factors. There is evidence to support EVOO in improving SBP in patients with high blood pressure, with studies suggesting that specific phenols in the oil may be important compared with a refined olive oil. Compared with other dietary fats or low-fat diets, EVOO can decrease LDL-c and increase HDL-c. Diets including daily EVOO are effective for weight loss. The effect of EVOO on FBG compared with other diets is not yet clear. The authors state that EVOO would be a far superior choice compared with other dietary fats, low-fat diets, or refined olive oil. The daily use of EVOO starting at approximately two tablespoons a day will improve a range of risk factors in as few as three weeks.
Abstract
Most chronic diseases are preventable with a healthy diet, although there is debate about the optimal dietary approach. Increasingly more countries are focusing on food-based guidelines rather than the traditional nutrient-based approach. Although there is good agreement on plant foods, controversy remains about the types and amounts of fats and oils. This narrative review aims to systematically summarize and evaluate the latest evidence on the protective effects of extra virgin olive oil (EVOO) on disease risk factors. A systematic search of the relevant literature using PubMed, Cochrane Library, and Embase databases was conducted for the years 2000 through December 2022. A narrative synthesis was then undertaken. Of 281 retrieved articles, 34 articles fulfilled our inclusion criteria and were included. Compared with other dietary fats and low-fat diets, EVOO is superior in the management of clinical biomarkers including lowering blood pressure and LDL-c, increasing protective HDL-c, improving glycemic control, and weight management. The protective effects of EVOO are likely due to its polyphenol content rather than the monounsaturated fat content. It is therefore important to promote the regular use of EVOO in the context of healthy dietary patterns such as the Mediterranean diet for maximal health benefit.
-
4.
The entero-endocrine response following a mixed-meal tolerance test with a non-nutritive pre-load in participants with pre-diabetes and type 2 diabetes: A crossover randomized controlled trial proof of concept study.
Muilwijk, M, Beulens, JWJ, Groeneveld, L, Rutters, F, Blom, MT, Agamennone, V, van den Broek, T, Keijser, BJF, Hoevenaars, F
PloS one. 2023;18(8):e0290261
-
-
-
Free full text
Plain language summary
There is a process within the mouth and gut that is responsible for sensing nutrients and releasing hormones, which is called the entero-endocrine response. This response is responsible for ensuring that we do not overeat and maintain normal metabolism. The use of stevia, which is a sweetener, instead of sugar in food has been reported to have blood sugar lowering effects, which may be of benefit to individuals with type 2 diabetes (T2D). However, it is not fully understood how stevia can affect the entero-endocrine response, especially in individuals with T2D and prediabetes. This cross-over randomised control trial aimed to determine the entero-endocrine response in 20 individuals with either T2D or prediabetes following the consumption of stevia before a meal. The results showed that there was an enhanced entero-endocrine response to stevia in individuals with T2D compared to those with prediabetes. Blood sugar and the hormones responsible for lowering blood sugar and appetite suppression were all higher in individuals with T2D. There were no associations between the composition of the oral or gut microbiota and the entero-endocrine response. It was concluded that the consumption of stevia before a meal differentially effects the entero-endocrine response in individuals with T2D and prediabetes. This study could be used by healthcare professionals to understand that the consumption of stevia before a meal elicits an individual response. However, as this was a small study, further understanding of the mechanisms involved would be of benefit.
Abstract
INTRODUCTION This crossover randomized controlled trial (RCT) investigated differences in short-term entero-endocrine response to a mixed-meal tolerance test preceded by nutrient sensing between participants with pre-diabetes (pre-T2D) and type 2 diabetes (T2D). Additionally, differences in gut and oral microbiome composition between participants with a high and low entero-endocrine response were investigated. RESEARCH DESIGN AND METHODS Ten participants with pre-T2D and ten with T2D underwent three test days with pre-loads consisting of either swallowing water (control), or rinsing with a non-nutritive sweetener solution, or swallowing the sweetener solution before a mixed-meal tolerance test. Blood glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), glucagon, glucose, insulin and peptide YY (PYY) were determined at t = -20, 0, 15, 30, 60, 120 and 240 minutes. The composition of the oral and gut microbiome at baseline were also determined. RESULTS The entero-endocrine response differed by pre-loads, e.g. a lower PYY response after swallowing the non-nutritive sweetener (-3585.2pg/mL [95% CI: -6440.6; -729.8]; p = 0.01). But it also differed by T2D status, e.g. a higher glucose, glucagon and PYY response was found in participants with T2D, compared to those with pre-T2D. Evidence for associations between the oral and gut microbiome composition and the entero-endocrine response was limited. Still, the level of entero-endocrine response was associated with several oral microbiome measures. Higher oral anterior α-diversity was associated with a lower PYY response (e.g. Inverse Simpson index -1357pg/mL [95% CI -2378; -336; 1.24]), and higher oral posterior α-diversitywith a higher GIP response (e.g. Inverse Simpson index 6773pg/mL [95% CI 132; 13414]) in models adjusted for sex, age and T2D status. CONCLUSIONS Non-nutritive pre-loads influence the entero-endocrine response to a mixed-meal, and this effect varies based on (pre-)T2D status. The entero-endocrine response is likely not associated with the gut microbiome, and there is limited evidence for association with the α-diversity of the oral microbiome composition. TRIAL REGISTRATION Trial register: Netherlands Trial Register NTR7212, accessible through International Clinical Trials Registry Platform: ICTRP Search Portal (who.int).
-
5.
High-fiber diet ameliorates gut microbiota, serum metabolism and emotional mood in type 2 diabetes patients.
Chen, L, Liu, B, Ren, L, Du, H, Fei, C, Qian, C, Li, B, Zhang, R, Liu, H, Li, Z, et al
Frontiers in cellular and infection microbiology. 2023;13:1069954
-
-
-
Free full text
Plain language summary
Accumulating studies have demonstrated that there are strong correlations between type 2 diabetes mellitus (T2DM) and gut microbiota. A nutritious diet composed of an adequate level of dietary fibres could provide enough carbohydrates for the gut microbiota to ferment, and the microbial metabolites could provide energy supply and regulate the immune function of the host. The aim of this study was to analyse the changes in gut microbiota, serum metabolism and emotional mood of patients with T2DM after consumption of a high-fibre diet. This study was a randomised, open-label, parallel-group clinical trial in T2DM patients with a 4-week treatment period. Seventeen patients clinically diagnosed with T2DM enrolled in the clinical trial and were randomly assigned into two groups: the control group (n = 8) or the intervention group (n = 9). Results showed that the high-fibre diet (compared to the control group): - improved glucose homeostasis and lipid metabolism of participants with T2DM; - decreased serum levels of inflammatory chemokines in participants with T2DM; - alleviated depression and anxiety symptoms, particularly by the uptake of more diverse carbohydrates in the diet in participants with T2DM; - enhanced the diversity of gut microbiota in the treatment group. Authors conclude that the dietary source of fibre demonstrated protective impacts on the gut ecosystem, and the alteration of the gut microbiota composition improved the glucose homeostasis in patients with T2DM.
Abstract
Previous studies have demonstrated that patients with type 2 diabetes mellitus (T2DM) often had the problems of fecal microbiota dysbiosis, and were usually accompanied with psychiatric comorbidities (such as depression and anxiety). Here, we conducted a randomized clinical study to analyze the changes in gut microbiota, serum metabolism and emotional mood of patients with T2DM after consumption of a high-fiber diet. The glucose homeostasis of participants with T2DM was improved by the high-fiber diet, and the serum metabolome, systemic inflammation and psychiatric comorbidities were also altered. The increased abundances of Lactobacillus, Bifidobacterium and Akkermansias revealed that the proportions of beneficial gut microbes were enriched by the high-fiber diet, while the abundances of Desulfovibrio, Klebsiella and other opportunistic pathogens were decreased. Therefore, the current study demonstrated that the intestinal microbiota alterations which were influenced by the high-fiber diet could improve the serum metabolism and emotional mood of patients with T2DM.
-
6.
Effect of aerobic exercise, slow deep breathing and mindfulness meditation on cortisol and glucose levels in women with type 2 diabetes mellitus: a randomized controlled trial.
Obaya, HE, Abdeen, HA, Salem, AA, Shehata, MA, Aldhahi, MI, Muka, T, Marques-Sule, E, Taha, MM, Gaber, M, Atef, H
Frontiers in physiology. 2023;14:1186546
-
-
-
-
Free full text
Plain language summary
Stress is considered to be an important factor in type 2 diabetes mellitus (T2DM) and aerobic exercise can help modulate the stress response as well as being important in the management of diabetes. Mindfulness meditation and deep breathing have also been shown to have positive effects on both stress and T2DM. This 6-week single-blind, randomised, controlled trial evaluated the effect of 10 min slow deep breathing and 10 min mindfulness meditation following a 40 min aerobic exercise programme, compared to the 40 min aerobic exercise alone, on fasting blood glucose (FBG) and cortisol levels in 58 stressed women with T2DM. FBG and cortisol levels improved in both groups but more so in the group who received the deep breathing and mindfulness meditation in addition to the exercise intervention: 20% vs 30% reduction in cortisol and 10% vs 15% reduction in FBG. The authors conclude that adding slow deep breathing and mindfulness meditation to an exercise programme may be useful in the management of stressed women with T2DM and reduce their cardiometabolic risk.
Expert Review
Conflicts of interest:
None
Take Home Message:
Practitioners could consider slow deep breathing and mindfulness meditation, added to aerobic exercise, as potentially useful components of the T2DM management program for stressed women.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
Stress, a key factor for Type 2 diabetes mellitus (T2DM), stimulates the hypothalamus-pituitary-adrenal gland (HPA) and triggers parasympathetic nerve withdrawal, leading to increased circulating cortisol levels and higher levels of blood glucose. Exercise is a key intervention that can modulate the HPA axis and help manage stress.
Methods
Fifty-eight women (aged between 40-50), diagnosed with T2DM for at least 5 years but medically stable with moderate to high stress scores were randomised to either aerobic training (AT) or aerobic exercise combined with slow deep breathing and mindfulness meditation (DMM) training three times weekly over 6-weeks.
AT group performed aerobic exercise on a treadmill at an intensity of 60%– 75% of the maximum heart rate for a total of 40 min, including a 5 minute warm up and 5 min cool down.
AT + DMM group performed a combination of aerobic exercise as per the AT group followed by a total of 10 minutes of diaphragmatic slow, deep breathing; and mindfulness meditation.
Results
Both groups showed a change from baseline in serum cortisol to p<0.0001
At 6 weeks in the AT + DMM group, the primary outcome of serum cortisol (nmol/L) levels was 12.59 nmol/L [95% CI 4.45-6.52] a decrease of 30.29% and the fasting blood glucose levels (secondary outcome) was 136.37mg/dl (95% CI: 9.19–2.6) a decrease of 14.54%
In the AT group performing only aerobic exercise decreased serum cortisol levels by 20.16% and FBG levels decreased by 9.97%.
Conclusion
This study showed that combining slow deep breathing and mindfulness meditation with aerobic exercise reduced the serum cortisol (p = 0.01) and FBG levels (p = 0.001) in women with T2DM compared to when only aerobic training was performed.
Clinical practice applications:
Consider a combined therapy approach with diaphragmatic breathing exercises and aerobic exercises that targets both the endocrine and autonomic nervous systems, as this may have a synergistic effect to assist with maintaining normal blood sugar levels and cortisol levels in individuals with T2DM.
Considerations for future research:
Future research is needed to determine the most effective combination of therapies for managing both FBG and serum cortisol levels in individuals with T2DM.
Abstract
Background: Aerobic exercise combined with breathing exercise can be an integral part of diabetes mellitus treatment. This single-center, randomized, parallel-group study investigated the effect of the combination of aerobic exercise with slow deep breathing and mindfulness meditation on the glucose and cortisol levels of women with type 2 diabetes mellitus (T2DM). Materials and Methods: Fifty-eight middle-aged women with T2DM (mean age: 45.67 ± 2.92 years) were randomly assigned to either the aerobic training group (AT: n = 29; mean age [46.1 ± 2.7 years]) or the aerobic exercise combined with slow deep breathing and mindfulness meditation (AT + DMM: n = 29; mean age [45.24 ± 3.14 years]). Aerobic exercise was performed at 60%-75% of the maximum heart rate. The women in each group were asked to perform the training three times weekly over a 6-week period. The duration of each session was 40 min for the AT group and 60 min for the AT + DMM group. The two groups were asked to perform aerobic exercise at 60%-75% of the maximum heart rate. Their fasting blood glucose (FBG) and serum cortisol levels were measured at the baseline and after the 6 weeks. Results: Compared with the AT group, the group undertaking 6 weeks of aerobic training combined with slow, deep breathing exercises and mindfulness meditation showed significantly lower levels of FBG (p = 0.001) and cortisol levels (p = 0.01) than the AT group. Conclusion: The addition of slow deep breathing and mindfulness meditation to aerobic exercise can better control the glucose and cortisol levels of women with T2DM and thereby improve their outcomes and decrease their cardiometabolic risk.
-
7.
Cognitive behavioral therapy for lifestyle changes in patients with obesity and type 2 diabetes: a systematic review and meta-analysis.
Kurnik Mesarič, K, Pajek, J, Logar Zakrajšek, B, Bogataj, Š, Kodrič, J
Scientific reports. 2023;13(1):12793
-
-
-
Free full text
Plain language summary
Obesity and type 2 diabetes mellitus (T2DM) are two of the most common chronic diseases and lifestyle modification, including diet, exercise and weight management, are recognised as important for prevention. Cognitive behavioural therapy (CBT) has been shown to contribute to lifestyle modification. The aim of this meta-analysis was to evaluate the effect of CBT, compared to no intervention/standard care only, in patients with obesity and/or T2DM, with a focus on health outcomes and implementation of changes long-term. Nine randomised controlled trials (RCT) with 902 participants were included in this meta-analysis. The health outcomes included weight loss and maintenance and glycosylated haemoglobin (HbA1c, a measure of blood glucose control) whilst the lifestyle changes included diet, physical activity, smoking, and compliance with treatments. There was a statistically significant benefit of CBT for weight loss and weight maintenance (based on 3 RCTs each) with a medium effect size, but no significant effect on HbA1c (based on 3 RCTs). In all 3 RCTs that evaluated depression, a significant benefit was observed. As the behavioural outcomes were too heterogenous to be pooled for a meta-analysis, they were reviewed in a descriptive manner only. Benefits were reported in terms of better dietary choices/reduced energy intake, increased physical activity, better adherence to medication and glucose monitoring as well as a reduction in smoking. The authors suggest that CBT appears to be moderately effective in promoting lifestyle modifications and weight loss.
Abstract
The aim of this systematic review and meta-analysis was to examine the contribution of cognitive behavioral therapy (CBT) to the implementation of lifestyle changes, considering health-related and behavioral outcomes. A systematic literature review was performed using multiple databases (PsycInfo, PubMed and MEDLINE). The inclusion criteria comprised randomised controlled trials of CBT for lifestyle changes in patients with obesity and/or type 2 diabetes. The quality of study reporting was assessed with the revised Cochrane Collaboration's risk of bias tool. A meta-analysis was conducted on studies with appropriate outcomes. Nine randomised controlled trials, with a total sample size of 902 participants, met the inclusion criteria. The meta-analysis has shown a medium, significant effect size of CBT interventions for weight loss and weight maintenance, and a low, non-significant effect size of CBT interventions for reducing glycated hemoglobin (HbA1c) levels. A separate, combined, meta-analysis for all nine calculated effect sizes has yielded a medium and significant overall effect size for the model. Our review of the studies about the effectiveness of CBT in implementing lifestyle changes has, in comparison to usual control groups, proven the efficacy of CBT interventions in implementing lifestyle changes, especially for weight loss and weight maintenance.
-
8.
Impact of dietary interventions on pre-diabetic oral and gut microbiome, metabolites and cytokines.
Shoer, S, Shilo, S, Godneva, A, Ben-Yacov, O, Rein, M, Wolf, BC, Lotan-Pompan, M, Bar, N, Weiss, EI, Houri-Haddad, Y, et al
Nature communications. 2023;14(1):5384
-
-
-
Free full text
Plain language summary
Pre-diabetes, a condition characterized by elevated blood glucose levels but below diabetes thresholds, is a significant risk factor for the development of type 2 diabetes, as well as other comorbidities including cardiovascular and kidney diseases. Diet plays a critical role in the development of hyperglycaemia and the onset of pre-diabetes. The aim of this study was to assess the impact of a personalized postprandial glucose-targeting diet (PPT), as well as the standard of care Mediterranean diet (MED), on the oral and gut microbiome, metabolites and cytokines in 200 pre-diabetic individuals. This study was a biphasic, randomised, controlled, single-blind dietary intervention. Phase one included a six-month intervention that compared two diets targeting glycaemic control, while phase two included a six-month follow-up period. Participants (n = 225) were randomly assigned in a 1:1 ratio to a PPT (n = 113) or a MED (n = 112). Results showed that participants assigned to the PPT diet had significant changes in 19 gut microbial species, 14 gut and one oral microbial pathway, 86 serum metabolites and four cytokines. Participants assigned to the MED diet showed significant changes in five gut and one oral microbial species, 18 gut microbial pathways, 27 serum metabolites and four cytokines. Authors conclude that dietary interventions can affect the microbiome, cardiometabolic profile and immune response of the host. Thus, diets such as the PPT used in this study, which takes into account microbiome features, could be designed to affect the microbiome and inflict desired metabolic outcomes.
Abstract
Diabetes and associated comorbidities are a global health threat on the rise. We conducted a six-month dietary intervention in pre-diabetic individuals (NCT03222791), to mitigate the hyperglycemia and enhance metabolic health. The current work explores early diabetes markers in the 200 individuals who completed the trial. We find 166 of 2,803 measured features, including oral and gut microbial species and pathways, serum metabolites and cytokines, show significant change in response to a personalized postprandial glucose-targeting diet or the standard of care Mediterranean diet. These changes include established markers of hyperglycemia as well as novel features that can now be investigated as potential therapeutic targets. Our results indicate the microbiome mediates the effect of diet on glycemic, metabolic and immune measurements, with gut microbiome compositional change explaining 12.25% of serum metabolites variance. Although the gut microbiome displays greater compositional changes compared to the oral microbiome, the oral microbiome demonstrates more changes at the genetic level, with trends dependent on environmental richness and species prevalence in the population. In conclusion, our study shows dietary interventions can affect the microbiome, cardiometabolic profile and immune response of the host, and that these factors are well associated with each other, and can be harnessed for new therapeutic modalities.
-
9.
Effect of a 12-Week Polyphenol Rutin Intervention on Markers of Pancreatic β-Cell Function and Gut Microbiota in Adults with Overweight without Diabetes.
Mathrani, A, Yip, W, Sequeira-Bisson, IR, Barnett, D, Stevenson, O, Taylor, MW, Poppitt, SD
Nutrients. 2023;15(15)
-
-
-
Free full text
Plain language summary
Rutin is a naturally ocurring chemical compound found in a variety of fruits and vegetables, but most notably citrus fruits. Previous studies in animals have indicated that rutin has antidiabetic properties and it is thought that this may be due to it acting as a prebiotic for the gut microbiota, which also have a role in decreasing inflammation and improving the body’s ability to balance blood sugar levels. This 12-week randomised control trial of 87 individuals with obesity and a risk of developing type 2 diabetes aimed to evaluate the intake of 500mg/day rutin on the functioning of the pancreatic cells that produce the hormone responsible for blood sugar balance known as insulin and gut microbiota composition. The results showed that rutin supplementation had no effect on pancreatic cell function or gut bacteria composition. It was concluded that rutin had no significant effect on type 2 diabetes related blood markers and overall gut microbiota composition. This study could be used by healthcare professionals to understand that 12-weeks of 500mg/day rutin is ineffective at stimulating the pancreatic cells associated with blood sugar control in those at risk of developing type 2 diabetes. However, more research should be considered on other mechanisms through which rutin may work to lower risk.
Abstract
Supplementation with prebiotic polyphenol rutin is a potential dietary therapy for type 2 diabetes prevention in adults with obesity, based on previous glycaemic improvement in transgenic mouse models. Gut microbiota are hypothesised to underpin these effects. We investigated the effect of rutin supplementation on pancreatic β-cell function measured as C-peptide/glucose ratio, and 16S rRNA gene-based gut microbiota profiles, in a cohort of individuals with overweight plus normoglycaemia or prediabetes. Eighty-seven participants were enrolled, aged 18-65 years with BMI of 23-35 kg/m2. This was a 12-week double-blind randomised controlled trial (RCT), with 3 treatments comprising (i) placebo control, (ii) 500 mg/day encapsulated rutin, and (iii) 500 mg/day rutin-supplemented yoghurt. A 2-h oral glucose tolerance test (OGTT) was performed at baseline and at the end of the trial, with faecal samples also collected. Compliance with treatment was high (~90%), but rutin in both capsule and dietary format did not alter pancreatic β-cell response to OGTT over 12 weeks. Gut bacterial community composition also did not significantly change, with Firmicutes dominating irrespective of treatment. Fasting plasma glucose negatively correlated with the abundance of the butyrate producer Roseburia inulinivorans, known for its anti-inflammatory capacity. This is the first RCT to investigate postprandial pancreatic β-cell function in response to rutin supplementation.
-
10.
A nutritional biomarker score of the Mediterranean diet and incident type 2 diabetes: Integrated analysis of data from the MedLey randomised controlled trial and the EPIC-InterAct case-cohort study.
Sobiecki, JG, Imamura, F, Davis, CR, Sharp, SJ, Koulman, A, Hodgson, JM, Guevara, M, Schulze, MB, Zheng, JS, Agnoli, C, et al
PLoS medicine. 2023;20(4):e1004221
-
-
-
Free full text
Plain language summary
Self-reported adherence to the Mediterranean diet (MedDiet) has been associated with a lower incidence of type 2 diabetes (T2D). However, as no biological indicators of whether people are really following the MedDiet have been recorded, it is difficult to definitively ascertain any associations. This post-hoc analysis of a randomised control trial and a cohort study aimed to determine indicative nutritional biomarkers associated with the MedDiet and to see if associations exist with the incidence of T2D. The study formulated a biomarker score based on 29 different nutrients that are in abundance in the MedDiet. This score was then applied to an observational study and showed that as the score went up and therefore adherence to the diet, the incidence of T2D went down and vice versa. Higher adherence to the MedDiet resulted in an 11% decrease in the incidence of T2D. It was concluded that adherence to the MedDiet may help to prevent T2D. This study could be used by healthcare professionals to recommend the commencement of the MedDiet in individuals who are risk of its development.
Abstract
BACKGROUND Self-reported adherence to the Mediterranean diet has been modestly inversely associated with incidence of type 2 diabetes (T2D) in cohort studies. There is uncertainty about the validity and magnitude of this association due to subjective reporting of diet. The association has not been evaluated using an objectively measured biomarker of the Mediterranean diet. METHODS AND FINDINGS We derived a biomarker score based on 5 circulating carotenoids and 24 fatty acids that discriminated between the Mediterranean or habitual diet arms of a parallel design, 6-month partial-feeding randomised controlled trial (RCT) conducted between 2013 and 2014, the MedLey trial (128 participants out of 166 randomised). We applied this biomarker score in an observational study, the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study, to assess the association of the score with T2D incidence over an average of 9.7 years of follow-up since the baseline (1991 to 1998). We included 22,202 participants, of whom 9,453 were T2D cases, with relevant biomarkers from an original case-cohort of 27,779 participants sampled from a cohort of 340,234 people. As a secondary measure of the Mediterranean diet, we used a score estimated from dietary-self report. Within the trial, the biomarker score discriminated well between the 2 arms; the cross-validated C-statistic was 0.88 (95% confidence interval (CI) 0.82 to 0.94). The score was inversely associated with incident T2D in EPIC-InterAct: the hazard ratio (HR) per standard deviation of the score was 0.71 (95% CI: 0.65 to 0.77) following adjustment for sociodemographic, lifestyle and medical factors, and adiposity. In comparison, the HR per standard deviation of the self-reported Mediterranean diet was 0.90 (95% CI: 0.86 to 0.95). Assuming the score was causally associated with T2D, higher adherence to the Mediterranean diet in Western European adults by 10 percentiles of the score was estimated to reduce the incidence of T2D by 11% (95% CI: 7% to 14%). The study limitations included potential measurement error in nutritional biomarkers, unclear specificity of the biomarker score to the Mediterranean diet, and possible residual confounding. CONCLUSIONS These findings suggest that objectively assessed adherence to the Mediterranean diet is associated with lower risk of T2D and that even modestly higher adherence may have the potential to reduce the population burden of T2D meaningfully. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12613000602729 https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=363860.