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Effect of two different sublingual dosages of vitamin B12 on cobalamin nutritional status in vegans and vegetarians with a marginal deficiency: A randomized controlled trial.
Del Bo', C, Riso, P, Gardana, C, Brusamolino, A, Battezzati, A, Ciappellano, S
Clinical nutrition (Edinburgh, Scotland). 2019;38(2):575-583
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Vitamin B12 (cyanocobalamin) represents an important and essential water-soluble nutrient involved in the formation of erythrocytes, in the maintenance of the central nervous system, and in cognitive performance. The aim of this study was to evaluate the ability of two different doses (350ug/week vs 2000 mg/week) of sublingual supplements in improving the nutritional status of cyanocobalamin in a group of vegans and vegetarians with a marginal deficiency. Forty subjects were enrolled and randomly divided into two groups of 20 subjects each for a 12-week double-blind (participants and outcome assessors), randomised, controlled, parallel dietary intervention study. Results indicate that as a little as 350ug per week of vitamin B12 supplementation was enough to correct a marginal deficiency of cobalamin and to improve biomarkers of cobalamin status in a group of vegans and vegetarians. Authors conclude that even though vitamin B12 supplementation is important for vegetarians and vegans with a marginal deficiency, the absence of a consensus on vitamin B12 cut-off values and the high individual variability make it difficult to identify the real needs for vegans and vegetarians.
Abstract
BACKGROUND & AIMS Vegetarians and vegans are more vulnerable to vitamin B12 deficiency with severe risks of megaloblastic anemia, cognitive decline, neuropathy, and depression. An easy and simple method of supplementation consists of taking one weekly dosage of 2000 μg. However, single large oral doses of vitamin B12 are poorly absorbed. The present research evaluates the ability of two different sublingual dosages of vitamin B12 (350 μg/week vs 2000 μg/week) in improving cyanocobalamin (vitamin B12) nutritional status in vegans and vegetarians with a marginal deficiency. METHODS A 12-week randomized, double-blind, controlled, parallel intervention trial was performed. Forty subjects with marginal vitamin B12 deficiency were enrolled and randomly divided into two groups: test group Ld (low dose, 350 μg/week) and control group Hd (high dose, 2000 μg/week) vitamin B12 supplementation. Blood samples were collected at baseline and after 15, 30, 60, and 90 days from the intervention for the determination of vitamin B12, related metabolic markers, and blood cell counts. RESULTS Two-way analysis of variance showed a significant effect of time (P < 0.0001) and of time × treatment interaction (P = 0.012) on serum concentration of vitamin B12 that increased after 90-day supplementation (Ld and Hd) compared to baseline. Both the supplements increased (P < 0.0001, time effect) the levels of holotranscobalamin, succinic acid, methionine and wellness parameter, while decreased (P < 0.0001, time effect) the levels of methylmalonic acid, homocysteine and folate compared to baseline. No difference was observed between groups (Ld vs Hd). No effect was detected for vitamin B6 and blood cell count. CONCLUSIONS In our experimental conditions, both supplements were able to restore adequate serum concentrations of vitamin B12 and to improve the levels of related metabolic blood markers in subjects with a marginal deficiency. The results support the use of a sublingual dosage of 50 μg/day (350 μg/week) of cobalamin, instead of 2000 μg/week (provided as a single dose), to reach a state of nutritional adequacy of vitamin B12 in this target population. This study was registered at www.isrctn.org as ISRCTN75099618.
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Plant-Based Diets Are Associated With a Lower Risk of Incident Cardiovascular Disease, Cardiovascular Disease Mortality, and All-Cause Mortality in a General Population of Middle-Aged Adults.
Kim, H, Caulfield, LE, Garcia-Larsen, V, Steffen, LM, Coresh, J, Rebholz, CM
Journal of the American Heart Association. 2019;8(16):e012865
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Plant based diets have been associated with better health outcomes, however mixed results have been shown on their relationship with death by any cause and death due to heart disease. This cohort study of 15792 middle aged people aimed to determine if plant-based diets are associated with a lower risk of heart disease, death due to heart disease or death due to any cause and whether this was on a sliding scale depending on adherence to a healthful plant-based diet. The results showed that individuals following a plant-based diet had a 16% lower risk of heart disease, 32% lower risk of death due to heart disease and a 25% lower risk of death by any cause and individuals who followed a healthier plant-based diet were at an even lower risk of heart disease, death due to heart disease and death due to any cause. Interestingly when margarine was included in an individual’s diet, the decreased risk of heart disease was attenuated. It was concluded that higher adherence to a healthy plant-based diet was associated with a lower risk of heart disease, death due to heart disease and death by any cause. This study could be used by healthcare practitioners to recommend a plant-based diet to those at an increased risk of heart disease.
Abstract
Background Previous studies have documented the cardiometabolic health benefits of plant-based diets; however, these studies were conducted in selected study populations that had narrow generalizability. Methods and Results We used data from a community-based cohort of middle-aged adults (n=12 168) in the ARIC (Atherosclerosis Risk in Communities) study who were followed up from 1987 through 2016. Participants' diet was classified using 4 diet indexes. In the overall plant-based diet index and provegetarian diet index, higher intakes of all or selected plant foods received higher scores; in the healthy plant-based diet index, higher intakes of only the healthy plant foods received higher scores; in the less healthy plant-based diet index, higher intakes of only the less healthy plant foods received higher scores. In all indexes, higher intakes of animal foods received lower scores. Results from Cox proportional hazards models showed that participants in the highest versus lowest quintile for adherence to overall plant-based diet index or provegetarian diet had a 16%, 31% to 32%, and 18% to 25% lower risk of cardiovascular disease, cardiovascular disease mortality, and all-cause mortality, respectively, after adjusting for important confounders (all P<0.05 for trend). Higher adherence to a healthy plant-based diet index was associated with a 19% and 11% lower risk of cardiovascular disease mortality and all-cause mortality, respectively, but not incident cardiovascular disease (P<0.05 for trend). No associations were observed between the less healthy plant-based diet index and the outcomes. Conclusions Diets higher in plant foods and lower in animal foods were associated with a lower risk of cardiovascular morbidity and mortality in a general population.
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Gut feelings: A randomised, triple-blind, placebo-controlled trial of probiotics for depressive symptoms.
Chahwan, B, Kwan, S, Isik, A, van Hemert, S, Burke, C, Roberts, L
Journal of affective disorders. 2019;253:317-326
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Depression is a debilitating psychiatric disorder that is the leading cause of disability world-wide. Multiple causes of depression have been identified, including genetic, neurological, inflammatory, personality, cognitive, and environmental factors. The aim of this study was to investigate the effectiveness of the multispecies probiotic Ecologic® Barrier for reducing symptoms in adults with mild to severe levels of depression. The study was a triple-blinded parallel, placebo-controlled randomised clinical trial. Participants were randomly allocated into two groups; probiotic and placebo. 71 participants with depressive symptoms were recruited and allocated sequentially over 12 months. Results indicate that all participants across both probiotic and placebo groups exhibited a reduction in depressive symptoms over the time-period of the trial. Thus, the routine involved with daily preparation and consumption of the probiotic and scheduled appointments, as well as involvement in these behaviours with the aim of seeking improvement in depressive symptoms had positive impacts on mood, irrespective of whether the probiotic or placebo was consumed. Authors conclude that their findings offer evidence to indicate that probiotic consumption can exert change on cognitive patterns associated with depression.
Expert Review
Conflicts of interest:
None
Take Home Message:
- This study offers evidence to indicate that probiotic consumption can exert change on cognitive patterns associated with depression.
- The study suggests that probiotics, rather than having a direct effect on depressive symptoms, potentially act on immune system activity, inflammation and gut barrier integrity which contribute to the expression of depression.
- Probiotics may be a useful adjunct to potentiate the effects of other therapies, such as CBT.
- This study points to the validity of managing physical health as part of mental health treatment.
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:
With evidence suggesting that decreased gut barrier function and inflammation are correlated with depression, this study set out to determine the effect of consumption of probiotic supplements on depressive symptoms from a sample of 71 participants with depression. The study was a triple-blinded parallel, placebo-controlled randomised clinical trial conducted over 8 weeks in Australia. Pre and post intervention measures of symptoms and vulnerability markers of depression as well as gut microbiota were compared alongside psychological variables and gut microbiota composition to non-depressed, placebo and probiotic groups. All the clinical trial participants demonstrated an improvement in symptoms – participants in the probiotic group demonstrated a significantly greater reduction in cognitive reactivity compared with the placebo group. Probiotics did not significantly alter the microbiota of depressed individuals, however a significant correlation was found between Ruminococcus gnavus and one of the metrics for depression.
Clinical practice applications:
This study was small and carried out over a short period of time. While significant results were found, which signify potential considerations for clinical practice, the results from this study do not offer evidence that the probiotics used had a direct effect on depressive symptoms – they suggest that probiotics potentially act on cognitive processes contributing to depression which may include immune system activity, inflammation, and gut barrier integrity. Overall, this study offers evidence to indicate that probiotic consumption can exert change on cognitive patterns associated with depression. In clinical practice, probiotics may be a useful adjunct to potentiate the effects of therapies, such as CBT. Finally, the use of probiotics promotes the concept of managing physical health as part of mental health treatment.
Considerations for future research:
These preliminary results are promising and offer a number of future research and clinical avenues to build upon. The results do however, indicate that a longer trial may be needed to fully assess the effects of probiotics on mood and the mechanisms by which probiotics may be influencing this. The study also suggests that further research using a range of concentrations in a dose response study may be warranted to determine the optimal dose; a greater dose over a longer period may produce detectable changes in microbiota as well as further differences in psychological data.
Abstract
BACKGROUND Depression is the leading cause of disability worldwide; with evidence suggesting that decreased gut barrier function and inflammation are correlated with depressive symptoms. We conducted a clinical trial to determine the effect of consumption of probiotic supplements (Winclove's Ecologic® Barrier) on depressive symptoms in a sample of participants with mild to severe depression. METHOD 71 participants were randomly allocated to either probiotic or placebo, which was, consumed daily over eight weeks. Pre- and post-intervention measures of symptoms and vulnerability markers of depression as well as gut microbiota composition were compared. Clinical trial participants were also compared on psychological variables and gut microbiota composition to a non-depressed group (n = 20). RESULTS All clinical trial participants demonstrated improvement in symptoms, suggesting non-specific therapeutic effects associated with weekly monitoring visits. Participants in the probiotic group demonstrated a significantly greater reduction in cognitive reactivity compared with the placebo group, particularly in the mild/moderate subgroup. Probiotics did not significantly alter the microbiota of depressed individuals, however, a significant correlation was found between Ruminococcus gnavus and one depression metric. LIMITATIONS There was a high attrition rate, which may be attributed to weekly monitoring visits. Additionally, modulation of the gut microbiota may need more specific testing to distinguish subtle changes. CONCLUSIONS While microbiota composition was similar between all groups, probiotics did affect a psychological variable associated with susceptibility to depression. Further research is needed to investigate how probiotics can be utilised to modify mental wellbeing, and whether they can act as an adjunct to existing treatments.
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Effect of a Nutritional and Behavioral Intervention on Energy-Reduced Mediterranean Diet Adherence Among Patients With Metabolic Syndrome: Interim Analysis of the PREDIMED-Plus Randomized Clinical Trial.
Sayón-Orea, C, Razquin, C, Bulló, M, Corella, D, Fitó, M, Romaguera, D, Vioque, J, Alonso-Gómez, ÁM, Wärnberg, J, Martínez, JA, et al
JAMA. 2019;322(15):1486-1499
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Excess caloric intake and poor nutritional quality are associated with overweight and obesity. A traditional Mediterranean diet has been shown to reduce all-cause mortality, and in particular to reduce risk of cardiovascular disease, type 2 diabetes mellitus and overweight. The aim of this randomised, prospective, single-blinded study was to evaluate the effectiveness of an intensive lifestyle intervention programme in 6874 overweight or obese men and women with metabolic syndrome in Spain. The intervention group was advised on an energy-reduced Mediterranean diet and exercise and received behavioural support, with initial group sessions and interviews, and monthly follow-up phone calls for one year. The control group received advice on a Mediterranean diet and usual care, with 6 monthly follow-ups. After 12 months, the more intensively counselled patients showed a significantly better adherence to an energy-reduced Mediterranean diet than the control group. They had greater reductions in refined grains, pastries, red and processed meats and greater increases in vegetable, fruit and nut consumption than the control group. The intervention group had also better improvements in cardiovascular risk factors.
Abstract
Importance: High-quality dietary patterns may help prevent chronic disease, but limited data exist from randomized trials about the effects of nutritional and behavioral interventions on dietary changes. Objective: To assess the effect of a nutritional and physical activity education program on dietary quality. Design, Setting, and Participants: Preliminary exploratory interim analysis of an ongoing randomized trial. In 23 research centers in Spain, 6874 men and women aged 55 to 75 years with metabolic syndrome and no cardiovascular disease were enrolled in the trial between September 2013 and December 2016, with final data collection in March 2019. Interventions: Participants were randomized to an intervention group that encouraged an energy-reduced Mediterranean diet, promoted physical activity, and provided behavioral support (n = 3406) or to a control group that encouraged an energy-unrestricted Mediterranean diet (n = 3468). All participants received allotments of extra-virgin olive oil (1 L/mo) and nuts (125 g/mo) for free. Main Outcomes and Measures: The primary outcome was 12-month change in adherence based on the energy-reduced Mediterranean diet (er-MedDiet) score (range, 0-17; higher scores indicate greater adherence; minimal clinically important difference, 1 point). Results: Among 6874 randomized participants (mean [SD] age, 65.0 [4.9] years; 3406 [52%] men), 6583 (96%) completed the 12-month follow-up and were included in the main analysis. The mean (SD) er-MedDiet score was 8.5 (2.6) at baseline and 13.2 (2.7) at 12 months in the intervention group (increase, 4.7 [95% CI, 4.6-4.8]) and 8.6 (2.7) at baseline and 11.1 (2.8) at 12 months in the control group (increase, 2.5 [95% CI, 2.3-2.6]) (between-group difference, 2.2 [95% CI, 2.1-2.4]; P < .001). Conclusions and Relevance: In this preliminary analysis of an ongoing trial, an intervention that encouraged an energy-reduced Mediterranean diet and physical activity, compared with advice to follow an energy-unrestricted Mediterranean diet, resulted in a significantly greater increase in diet adherence after 12 months. Further evaluation of long-term cardiovascular effects is needed. Trial Registration: isrctn.com Identifier: ISRCTN89898870.
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Effects of Yeast (1,3)-(1,6)-Beta-Glucan on Severity of Upper Respiratory Tract Infections: A Double-Blind, Randomized, Placebo-Controlled Study in Healthy Subjects.
Dharsono, T, Rudnicka, K, Wilhelm, M, Schoen, C
Journal of the American College of Nutrition. 2019;38(1):40-50
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Upper respiratory tract infections (URTIs) significantly impact the quality of life in susceptible individuals and account for considerable economic costs in days of work lost and medical visits. Previous studies have shown that URTIs may be reduced by the consumption of yeast beta-glucans through their affect on the immune system. This randomised double-blind placebo controlled study aimed to investigate whether the incidence and severity of the common cold could be altered by consumption of yeast (1,3)-(1,6)-beta-glucan. 291 subjects susceptible to URTI’s were randomly assigned to placebo or (1,3)-(1,6)-beta-glucan for 16-weeks. There were no statistically significant differences on overall symptom severity or duration of URTIs with beta-glucans at 16 weeks. Feelings of joy were significantly reduced with placebo. Further analysis showed that the beta-glucan group did experience reduced severity of symptoms in the first 7 days of contracting the URTI. Interesting to note was a significant reduction in blood pressure with beta-glucans, which was even more pronounced in subjects with clinically high blood pressure. Nutrition practitioners working with individuals suffering from chronic URTIs may wish to consider beta-glucans for their ability to reduce symptom severity in the first week of infection and increase feelings of wellbeing.
Abstract
OBJECTIVES Each year, adults suffer about two to four upper respiratory tract infections (URTIs), mostly in winter. The aim of the study was to evaluate the effects of brewers' yeast (1,3)-(1,6)-beta-glucan on incidence and severity of upper respiratory tract infections (URTIs). METHODS Generally healthy men and women (n = 299) reporting at least three URTIs during the previous year were randomized to receive either a placebo or 900 mg of yeast beta-glucan daily for 16 weeks during winter. In cases of acute URTI, the severity of URTI symptoms was assessed via the WURSS-21 questionnaire and the Jackson scale, and a clinical confirmation was implemented by the investigator. RESULTS Overall, 70 subjects under placebo and 71 subjects under yeast beta-glucan experienced at least one clinically confirmed URTI episode. The global severity using WURSS-21 had been quite similar between the study groups (p = 0.5267), whereas during the first days of URTIs the severity was less pronounced in the yeast beta-glucan group. On the episode level, the severity of physical symptoms was significantly lower for all investigated time intervals up to 7 days under yeast beta-glucan (WURSS (Q2-11) (days 1-2: p = 0.0465, days 1-3: p = 0.0323, days 1-4: p = 0.0248, days 1-7: p = 0.0278), also confirmed for the Jackson scale). The reduction of severity was accompanied by a significant increase in the joy subscore of the Perceived Stress Questionnaire (PSQ20) (p = 0.0148). In addition, there was a reduction of systolic (p = 0.0458) and diastolic (p = 0.1439) blood pressure. CONCLUSION Subjects supplementing with yeast beta-glucan benefit by a reduced severity of physical URTI symptoms during the first week of an episode, even though the incidence and global severity of common colds could not be altered in comparison to placebo. Furthermore, accompanying benefits in terms of blood pressure and mood were identified. Altogether, yeast beta-glucan supports the immune function.
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Examining Weight Bias among Practicing Canadian Family Physicians.
Alberga, AS, Nutter, S, MacInnis, C, Ellard, JH, Russell-Mayhew, S
Obesity facts. 2019;12(6):632-638
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Weight bias represents negative attitudes and beliefs about individuals because of their weight. The aim of this study was to examine: a. weight bias in a national sample of family physicians in Canada, b. the relationships between weight bias, attitudes about treating patients with obesity, and how people with obesity are perceived as a burden to the public healthcare system. A probability sample of 400 currently practicing family physicians completed the survey by phone or online. Results show that most respondents were white (63.3%) men (61.3%) aged 45 years or older. The average total score of explicit weight bias was 2.95 (1.17) evaluated on a 7-point Likert scale. Furthermore, although weight bias was not present in the majority of the sample, it was present among some physicians. Authors conclude that future work is needed to investigate weight bias reduction techniques targeted at physicians.
Abstract
OBJECTIVES The aim of this study was to examine the attitudes of practicing Canadian family physicians about individuals with obesity, their healthcare treatment, and perceptions of obesity treatment in the public healthcare system. METHOD A national sample of Canadian practicing family physicians (n = 400) completed the survey. Participants completed measures of explicit weight bias, attitudes towards treating patients with obesity, and perceptions that people with obesity increase demand on the public healthcare system. RESULTS Responses consistent with weight bias were not observed overall but were demonstrated in a sizeable minority of respondents. Many physicians also reported feeling frustrated with patients with obesity and agreed that people with obesity increase demand on the public healthcare system. Male physicians had more negative attitudes than females. More negative attitudes towards treating patients with obesity were associated with greater perceptions of them as a public health demand. CONCLUSION Results suggest that negative attitudes towards patients with obesity exist among some family physicians in Canada. It remains to be determined if physicians develop weight bias partly because they blame individuals for their obesity and its increased demand on the Canadian public healthcare system. More research is needed to better understand causes and consequences of weight bias among health professionals and make efforts towards its reduction in healthcare.
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Maternal allergen-specific IgG might protect the child against allergic sensitization.
Lupinek, C, Hochwallner, H, Johansson, C, Mie, A, Rigler, E, Scheynius, A, Alm, J, Valenta, R
The Journal of allergy and clinical immunology. 2019;144(2):536-548
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Analysis of allergen-specific IgE responses in birth cohorts with allergens has provided detailed information regarding the development of specific IgE responses in children. Data regarding early development of allergen-specific IgG is needed. The aim of this study is to investigate whether maternal allergen-specific IgG can protect against IgE sensitization in their children. Plasma samples were taken from mothers during the third trimester, cord blood, breast milk collected 2 months after delivery; and from children at 6, 12, and 60 months of age. These samples were analysed for IgG reactivity to 164 allergens in 99 families. IgE sensitizations to allergens were determined at 5 years of age in the children. Children who were IgE sensitized against an allergen at 5 years of age had significantly higher allergen-specific IgG levels than non-sensitised children. For all 164 tested allergens, children from mothers with higher levels of specific plasma IgG levels against an allergen had no IgE sensitizations against that allergen at 5 years of age. High levels of allergen-specific IgG in mothers during the third trimester and in cord blood seem to protect against allergic sensitization in offspring. This finding has implications for allergy prevention.
Abstract
BACKGROUND Analysis of allergen-specific IgE responses in birth cohorts with microarrayed allergens has provided detailed information regarding the evolution of specific IgE responses in children. High-resolution data regarding early development of allergen-specific IgG are needed. OBJECTIVE We sought to analyze IgG reactivity to microarrayed allergens in mothers during pregnancy, in cord blood samples, in breast milk, and in infants in the first years of life with the aim to investigate whether maternal allergen-specific IgG can protect against IgE sensitization in the offspring. METHODS Plasma samples from mothers during the third trimester, cord blood, breast milk collected 2 months after delivery, and plasma samples from children at 6, 12, and 60 months of age were analyzed for IgG reactivity to 164 microarrayed allergens (ImmunoCAP ISAC technology) in 99 families of the Swedish birth cohort Assessment of Lifestyle and Allergic Disease During Infancy (ALADDIN). IgE sensitizations to microarrayed allergens were determined at 5 years of age in the children. RESULTS Allergen-specific IgG reactivity profiles in mothers, cord blood, and breast milk were highly correlated. Maternal allergen-specific IgG persisted in some children at 6 months. Children's allergen-specific IgG production occurred at 6 months and reflected allergen exposure. Children who were IgE sensitized against an allergen at 5 years of age had significantly higher allergen-specific IgG levels than nonsensitized children. For all 164 tested allergens, children from mothers with increased (>30 ISAC standardized units) specific plasma IgG levels against an allergen had no IgE sensitizations against that allergen at 5 years of age. CONCLUSION This is the first detailed analysis of the molecular IgG recognition profile in mothers and their children in early life. High allergen-specific IgG reactivity in the mother's plasma and breast milk and in cord blood seemed to protect against allergic sensitization at 5 years of age.
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Ratios of specific IgG4 over IgE antibodies do not improve prediction of peanut allergy nor of its severity compared to specific IgE alone.
Datema, MR, Eller, E, Zwinderman, AH, Poulsen, LK, Versteeg, SA, van Ree, R, Bindslev-Jensen, C
Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology. 2019;49(2):216-226
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Ara h 1, 2, 3 and 6 are major peanut allergens. Peanut allergy sufferers are sensitized to at least one of these allergens, which can increase their risk of allergy symptoms and anaphylactic reactions. A component-resolved diagnosis using IgE has become an indispensable tool for distinguishing between tolerance, allergy, and risk of severe reactions. The blocking antibodies IgG4, IgG, and IgA may counteract IgE antibodies. This clinical trial, therefore, investigated the associations between component-specific IgG, IgE, IgG4, IgA antibodies and whole peanut extract by analysing the severity of the outcome and assessing the diagnostic accuracy of antibody levels and ratios to determine the severity level of peanut allergy. One hundred and sixty-two peanut sensitised tolerant and allergic subjects were examined using immunoCAP for specific antibody isotypes against peanut extract, Ara h1, 2, 3, 8 and 9. According to the study, specific IgE against Ara h 2 is the best biomarker to diagnose peanut allergy, distinguish peanut-allergic subjects from tolerant sensitised subjects, and estimate the severity of the reaction. Additionally, the ratio of IgG and IgG4 antibodies over IgE did not improve predictive accuracy. This study provides healthcare professionals with insight into the role of different antibody isotypes in testing and diagnosing peanut allergies.
Abstract
BACKGROUND IgG4 antibodies have been suggested to play a protective role in the translation of peanut sensitization into peanut allergy. Whether they have added value as diagnostic read-out has not yet been reported. OBJECTIVE To evaluate whether (a) peanut-specific IgG, IgG4 and/or IgA antibodies are associated with tolerance and/or less severe reactions and (b) they can improve IgE-based diagnostic tests. METHODS Sera of 137 patients with challenge-proven peanut allergy and of 25 subjects that tolerated peanut, both with known IgE profiles to peanut extract and five individual peanut allergens, were analyzed for specific IgG and IgG4 . Antibody levels and ratios thereof were associated with challenge outcome including symptom severity grades. For comparison of the discriminative performance, receiver operating characteristic curve (ROC) analysis was used. RESULTS IgE against Ara h 2 was significantly higher in allergic than in tolerant patients and associated with severity of reactions (P < 0.001) with substantial diagnostic capability (AUC 0.91, 95%CI 0.87-0.96 and 0.80, 95%CI 0.73-0.87, respectively). IgG and IgG4 were also positively associated albeit significantly weaker (AUCs from 0.65 to 0.72). On the other hand, ratios of IgG and IgG4 over IgE were greater in patients that were tolerant or had mild symptoms as compared to severe patients but they did not predict challenge outcomes better than IgE alone (AUCs from 0.54 to 0.89). CONCLUSION IgE against Ara h 2 is the best biomarker for predicting peanut challenge outcomes including severity and IgG and IgG4 antibody ratios over IgE do not improve these outcomes.
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Effects of Diet Based on IgG Elimination Combined with Probiotics on Migraine Plus Irritable Bowel Syndrome.
Xie, Y, Zhou, G, Xu, Y, He, B, Wang, Y, Ma, R, Chang, Y, He, D, Xu, C, Xiao, Z
Pain research & management. 2019;2019:7890461
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The causes of irritable bowel syndrome (IBS) are complex and not fully understood, yet the occurrence of migraine has been linked with this disease. As they have an association, therapies used for either disorder may have a direct impact on both. Food sensitivities have been shown to affect both migraines and IBS and the elimination of foods may be of benefit to both disorders. This randomised cross-over trial of 60 individuals with migraine and IBS assessed immune reactions to certain foods and aimed to determine the effect of eliminating these foods and the addition of probiotics on individuals with IBS and migraine. The results showed that after 14 weeks of treatment, only elimination diet combined with probiotics improved migraine and IBS symptoms, resulting in a decrease in the use of medications. Individuals treated with elimination diet or probiotics only did show an improvement in comparison to the start of the trial, however not when compared to the combination treatment It was concluded that elimination diet in combination with probiotics may be of benefit to relieve symptoms of migraine and IBS. This study could be used by healthcare professionals to understand possible causes of IBS and migraines, and that treatments may involve targeting both illnesses.
Abstract
Several research studies have revealed that migraine has a solid link with gastrointestinal diseases especially irritable bowel syndrome (IBS). This study was carried out to investigate therapeutic potential of diet based on IgG elimination combined with probiotics on migraine plus irritable bowel syndrome. A total of 60 patients diagnosed with migraine plus IBS were recruited for the study. IgG antibodies against 266 food varieties were detected by ELISA. Then, the subjects were randomized into three groups for treatment of IgG elimination diet or probiotics or diet combined with probiotics. Migraine symptom, gut function score, medication use, and serum serotonin level were measured at baseline, 7 weeks, and 14 weeks. Improvement of migraine and gut symptom was achieved at a certain time point. Reduced use of over-the-counter- (OTC-) analgesics was seen in all groups. However, use of triptans did not show significant difference. An increased serum serotonin level was seen in subjects treated with elimination diet and elimination diet combined with probiotics. IgG elimination diet combined with probiotics may be beneficial to migraine plus IBS. It may provide new insight by understanding the intricate relationship between migraine and gastrointestinal diseases.
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Broccoli consumption affects the human gastrointestinal microbiota.
Kaczmarek, JL, Liu, X, Charron, CS, Novotny, JA, Jeffery, EH, Seifried, HE, Ross, SA, Miller, MJ, Swanson, KS, Holscher, HD
The Journal of nutritional biochemistry. 2019;63:27-34
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Diet affects metabolic and gastrointestinal diseases, with the microbiome considered to be a mediating factor. Broccoli is a good source of fibre and phytochemicals including glucosinolates. The aim of this investigator-blinded, controlled feeding, randomised, crossover study was to evaluate the effects of broccoli on the composition and function of the microbiome. 18 healthy adults received 200 g cooked broccoli and 20 g raw daikon radish per day for 18 days in addition to a controlled, brassica-free diet or the same diet without the broccoli and daikon radish, with a 24-day washout period. A statistically significant increase in the ratio of Bacteroidetes to Firmicutes was observed following the broccoli intervention. When stratified by BMI above or below 25, this increase was only seen in those with a lower BMI whilst those with a higher BMI displayed a decrease in the ratio, although the latter was not statistically significant. In those with the lower BMI, there was also a correlation between the changes in the microbiota composition and glucosinolate metabolites. It was predicted that the involved changes would affect the functions of the endocrine system, transport and catabolism and energy metabolism. The authors concluded that eating broccoli may affect both the composition and the function of the microbiome.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Broccoli consumption at dosages of 200g per day were shown to change the composition of gastrointestinal microbiota, increasing Bacteroidetes and decreasing Firmicutes, and impact their function
- The observed results were strongest in those with a BMI of less than 26
- While interesting, the study only included 18 participants and therefore the results should be further confirmed.
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:
Introduction
There is growing evidence linking dysbiosis of the gastrointestinal microbiota and diet-induced gastrointestinal and metabolic diseases. Both long-term and acute dietary changes, fasting, eating frequency, and consumption of specific fibres and food phytochemicals play a role in shaping the composition and function of the microbiota, although evidence is lacking for specific foods. This study aimed to determine the impact of broccoli intake on the number of bacterial strains and their functional capacity.
Methods
This was a single-blind, randomised, crossover, complete feeding intervention. Study participants were healthy adults (n=18, females =10). Participants were requested to not eat Brassica vegetables for 3 weeks before the start of the study.
Subjects participated in two 18-day diet periods separated by a 24-hour washout, during which breakfast and dinner were consumed on site to observe compliance. The control diet was prepared using traditional American foods, excluding all Brassica vegetables. During the broccoli intervention period, participants consumed the same base diet with the addition of 200g of broccoli.
Faecal samples were collected on day 1, and day 16. Quantitative polymerase chain reaction was performed on bacterial strains. On day 17, time series plasma sampling and 24-hour urine collection was done.
Results
There was no difference in alpha diversity (a measure of microbiome diversity within a sample) between the two treatment periods. This indicates that no bacterial species were extinguished by broccoli treatment. Beta diversity analysis (a measure of the (dis)similarity between samples) indicated that bacterial communities were impacted by treatment (P=0.03).
After broccoli consumption, Bacteroidetes increased by 10% (P =0.03), while Firmicutes decreased by 8% (P=0.05). Overall the ratio of Bacteroidetes to Firmicutes increased by 37% (P=0.01) versus a 5% decrease in the control period. The Bacteroides genus increased by 6% (P=0.02) versus a 2% decrease in the control period.
Interestingly, the effects were most strong in those with a lower BMI (< 26 kg/m2) who had an increase in metabolites after broccoli consumption. Algorithms to predict the function of the microbiota showed that broccoli increased endocrine (P=0.05), energy metabolism (P=0.01), transport and catabolism (P=0.04) pathways.
Conclusion
Broccoli intake, at 200g daily, changes the composition and potentially impacts the function of the gut microbiota.
Clinical practice applications:
- Studies like this allow practitioners to focus on specific foods in specific quantities to positively alter the microbiota and their function
- Cruciferous vegetables, like broccoli, kale, cauliflower, cabbage, Brussel sprouts, are an important group as they contain fibre and phytonutrients such as glucosinolates. These compounds can be metabolised by the microbiota into active compounds with health benefits. This study has shown the bidirectional benefit of broccoli consumption in that it can positively impact the function and composition of the microbiota
- Interestingly, the results in this small study were driven by participants with a BMI of less than 26. Sub-group analysis found no statistically significant relationships in participants with BMI >26
- It is worth noting that it is possible that the addition of 5g of fibre from the broccoli is also contributing to the changes observed.
Considerations for future research:
- Larger, controlled feeding studies that isolate specific foods to identify their effects on the microbiota are needed
- Genetic sequencing for only a few bacterial myrosinases has been completed and therefore future studies should aim to assess the metabolic capabilities in faecal samples such as myrosinase activity
- While this study and others have shown changes in the types of bacteria after cruciferous vegetable consumption the consistency of results has been mixed potentially due to differing study designs and treatment dosages. Further studies to clarify and confirm these results would be beneficial
- To assess the function of the microbiota a predictive algorithm was used. This requires experimental confirmation by such methods as metabolite profiling and whole genome shotgun sequencing.
Abstract
The human gastrointestinal microbiota is increasingly linked to health outcomes; however, our understanding of how specific foods alter the microbiota is limited. Cruciferous vegetables such as broccoli are a good source of dietary fiber and phytonutrients, including glucosinolates, which can be metabolized by gastrointestinal microbes. This study aimed to determine the impact of broccoli consumption on the gastrointestinal microbiota of healthy adults. A controlled feeding, randomized, crossover study consisting of two 18-day treatment periods separated by a 24-day washout was conducted in healthy adults (n=18). Participants were fed at weight maintenance with the intervention period diet including 200 g of cooked broccoli and 20 g of raw daikon radish per day. Fecal samples were collected at baseline and at the end of each treatment period for microbial analysis. Beta diversity analysis indicated that bacterial communities were impacted by treatment (P=.03). Broccoli consumption decreased the relative abundance of Firmicutes by 9% compared to control (P=.05), increased the relative abundance of Bacteroidetes by 10% compared to control (P=.03) and increased Bacteroides by 8% relative to control (P=.02). Furthermore, the effects were strongest among participants with body mass index <26 kg/m2, and within this group, there were associations between bacterial relative abundance and glucosinolate metabolites. Functional prediction revealed that broccoli consumption increased the pathways involved in the functions of the endocrine system (P=.05), transport and catabolism (P=.04), and energy metabolism (P=.01). These results reveal that broccoli consumption affects the composition and function of the human gastrointestinal microbiota.