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Nutrients Sep 2020Diet modulates gut microbiota and plays an important role in human health. The aim of this study was to test the effect of a low-fat vegan diet on gut microbiota and its... (Randomized Controlled Trial)
Randomized Controlled Trial
Effects of a Low-Fat Vegan Diet on Gut Microbiota in Overweight Individuals and Relationships with Body Weight, Body Composition, and Insulin Sensitivity. A Randomized Clinical Trial.
Diet modulates gut microbiota and plays an important role in human health. The aim of this study was to test the effect of a low-fat vegan diet on gut microbiota and its association with weight, body composition, and insulin resistance in overweight men and women. We enrolled 168 participants and randomly assigned them to a vegan ( = 84) or a control group ( = 84) for 16 weeks. Of these, 115 returned all gut microbiome samples. Gut microbiota composition was assessed using uBiome Explorer™ kits. Body composition was measured using dual energy X-ray absorptiometry. Insulin sensitivity was quantified with the predicted clamp-derived insulin sensitivity index from a standard meal test. Repeated measure ANOVA was used for statistical analysis. Body weight decreased in the vegan group (treatment effect -5.9 kg [95% CI, -7.0 to -4.9 kg]; < 0.001), mainly due to a reduction in fat mass (-3.9 kg [95% CI, -4.6 to -3.1 kg]; < 0.001) and in visceral fat (-240 cm [95% CI, -345 to -135 kg]; < 0.001). PREDIcted M, insulin sensitivity index (PREDIM) increased in the vegan group (treatment effect +0.83 [95% CI, +0.48 to +1.2]; < 0.001). The relative abundance of Faecalibacterium prausnitzii increased in the vegan group (+5.1% [95% CI, +2.4 to +7.9%]; < 0.001) and correlated negatively with changes in weight (r = -0.24; = 0.01), fat mass (r = -0.22; = 0.02), and visceral fat (r = -0.20; = 0.03). The relative abundance of Bacteroides fragilis decreased in both groups, but less in the vegan group, making the treatment effect positive (+18.9% [95% CI, +14.2 to +23.7%]; < 0.001), which correlated negatively with changes in weight (r = -0.44; < 0.001), fat mass (r = -0.43; < 0.001), and visceral fat (r = -0.28; = 0.003) and positively with PREDIM (r = 0.36; < 0.001), so a smaller reduction in Bacteroides fragilis was associated with a greater loss of body weight, fat mass, visceral fat, and a greater increase in insulin sensitivity. A low-fat vegan diet induced significant changes in gut microbiota, which were related to changes in weight, body composition, and insulin sensitivity in overweight adults, suggesting a potential use in clinical practice.
Topics: Absorptiometry, Photon; Adult; Aged; Bacteroidetes; Body Composition; Body Mass Index; Body Weight; Diet; Diet, Fat-Restricted; Diet, Vegan; Exercise; Female; Firmicutes; Gastrointestinal Microbiome; Humans; Insulin Resistance; Intra-Abdominal Fat; Male; Middle Aged; Overweight
PubMed: 32987642
DOI: 10.3390/nu12102917 -
Vegan diet in young children remodels metabolism and challenges the statuses of essential nutrients.EMBO Molecular Medicine Feb 2021Vegan diets are gaining popularity, also in families with young children. However, the effects of strict plant-based diets on metabolism and micronutrient status of...
Vegan diets are gaining popularity, also in families with young children. However, the effects of strict plant-based diets on metabolism and micronutrient status of children are unknown. We recruited 40 Finnish children with a median age 3.5 years-vegans, vegetarians, or omnivores from same daycare centers-for a cross-sectional study. They enjoyed nutritionist-planned vegan or omnivore meals in daycare, and the full diets were analyzed with questionnaires and food records. Detailed analysis of serum metabolomics and biomarkers indicated vitamin A insufficiency and border-line sufficient vitamin D in all vegan participants. Their serum total, HDL and LDL cholesterol, essential amino acid, and docosahexaenoic n-3 fatty acid (DHA) levels were markedly low and primary bile acid biosynthesis, and phospholipid balance was distinct from omnivores. Possible combination of low vitamin A and DHA status raise concern for their visual health. Our evidence indicates that (i) vitamin A and D status of vegan children requires special attention; (ii) dietary recommendations for children cannot be extrapolated from adult vegan studies; and (iii) longitudinal studies on infant-onset vegan diets are warranted.
Topics: Adult; Child; Child, Preschool; Cross-Sectional Studies; Diet; Diet, Vegan; Diet, Vegetarian; Humans; Nutrients; Vegetarians
PubMed: 33471422
DOI: 10.15252/emmm.202013492 -
The American Journal of Clinical... Nov 2022Low-carbohydrate, high animal fat and protein diets have been promoted for weight loss and diabetes treatment. We therefore tested the effect of a low-carbohydrate vegan... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Low-carbohydrate, high animal fat and protein diets have been promoted for weight loss and diabetes treatment. We therefore tested the effect of a low-carbohydrate vegan diet in diabetes as a potentially healthier and more ecologically sustainable low-carbohydrate option.
OBJECTIVES
We sought to compare the effectiveness of a low-carbohydrate vegan diet with a moderate-carbohydrate vegetarian diet on weight loss and metabolic measures in diabetes.
METHODS
One hundred and sixty-four male and female participants with type 2 diabetes were randomly assigned to advice on either a low-carbohydrate vegan diet, high in canola oil and plant proteins, or a vegetarian therapeutic diet, for 3 mo, with both diets recommended at 60% of calorie requirements. Body weight, fasting blood, blood pressure, and 7-d food records, to estimate potential greenhouse gas emissions, were obtained throughout the study with tests of cholesterol absorption undertaken at baseline and end of study on 50 participants.
RESULTS
Both low-carbohydrate vegan and vegetarian diets similarly but markedly reduced body weight (-5.9 kg; 95% CI: -6.5, -5.28 kg; and -5.23 kg; 95% CI: -5.84, -4.62 kg), glycated hemoglobin (-0.99%; 95% CI: -1.07, -0.9%; and -0.88%; 95% CI: -0.97, -0.8%), systolic blood pressure (-4 mmHg; 95% CI: -7, -2 mmHg; and -6 mmHg; 95% CI: -8, -3 mmHg), and potential greenhouse gas emissions, but only for potential greenhouse gas emissions was there a significant treatment difference of -0.63 kgCO/d (95% CI: -0.99, -0.27 kgCO/d) favoring the low-carbohydrate vegan diet.
CONCLUSIONS
Low-carbohydrate vegan and vegetarian diets reduced body weight, improved glycemic control and blood pressure, but the more plant-based diet had greater potential reduction in greenhouse gas emissions.
TRIAL REGISTRATION NUMBER
clinicaltrials.gov identifier NCT02245399.
Topics: Humans; Diet, Vegan; Diabetes Mellitus, Type 2; Vegans; Greenhouse Gases; Blood Glucose; Weight Loss; Body Weight; Diet, Carbohydrate-Restricted
PubMed: 36156115
DOI: 10.1093/ajcn/nqac203 -
Obesity Reviews : An Official Journal... Sep 2022In parallel with an increased focus on climate changes and carbon footprint, the interest in plant-based diets and its potential health effects have increased over the... (Meta-Analysis)
Meta-Analysis Review
In parallel with an increased focus on climate changes and carbon footprint, the interest in plant-based diets and its potential health effects have increased over the past decade. The objective of this systematic review and meta-analysis was to examine the effect of vegan diets (≥12 weeks) on cardiometabolic risk factors in people with overweight or type 2 diabetes. We identified 11 trials (796 participants). In comparison with control diets, vegan diets reduced body weight (-4.1 kg, 95% confidence interval (CI) -5.9 to -2.4, p < 0.001), body mass index (BMI) (-1.38 kg/m , 95% CI -1.96 to -0.80, p < 0.001), glycated hemoglobin (HbA ) (-0.18% points, 95% CI -0.29 to -0.07, p = 0.002), total cholesterol (-0.30 mmol/L, 95% CI -0.52 to -0.08, p = 0.007), and low-density lipoprotein cholesterol (-0.24 mmol/L, 95% CI -0.40 to -0.07, p = 0.005). We identified no effect on blood pressure, high-density lipoprotein cholesterol, and triglycerides. We found that adhering to vegan diets for at least 12 weeks may be effective in individuals with overweight or type 2 diabetes to induce a meaningful decrease in body weight and improve glycemia. Some of this effect may be contributed to differences in the macronutrient composition and energy intake in the vegan versus control diets. Therefore, more research is needed regarding vegan diets and cardiometabolic health.
Topics: Body Weight; Cardiovascular Diseases; Cholesterol, HDL; Diabetes Mellitus, Type 2; Diet, Vegan; Humans; Overweight; Randomized Controlled Trials as Topic
PubMed: 35672940
DOI: 10.1111/obr.13462 -
European Journal of Nutrition Apr 2023Vitamin B is an essential nutrient that is not made by plants; consequently, unfortified plant-based foods are not a reliable supply. Recent estimates suggest high rates...
Vitamin B is an essential nutrient that is not made by plants; consequently, unfortified plant-based foods are not a reliable supply. Recent estimates suggest high rates of vitamin B deficiency among the vegetarian and vegan populations, particularly in pregnant women or women of child-bearing age who, for ethical and health reasons, are shifting towards higher consumption of plant-based foods in ever-increasing numbers. Vitamin B plays crucial metabolic roles across the life-course and in particular during pregnancy and in early development (first 1000 days of life). Evidence now implicates vitamin B deficiency with increased risk to a range of neuro, vascular, immune, and inflammatory disorders. However, the current UK recommended nutrient intake for vitamin B does not adequately consider the vitamin B deficit for those choosing a plant-based diet, including vegetarianism and in particular veganism, representing a hidden hunger. We provide a cautionary note on the importance of preventing vitamin B deficits for those individuals choosing a plant-based diet and the health professionals advising them.
Topics: Humans; Female; Pregnancy; Vitamin B 12; Diet; Diet, Vegetarian; Diet, Vegan; Vitamins
PubMed: 36469110
DOI: 10.1007/s00394-022-03025-4 -
Kardiologia Polska Aug 2020Dietary modification is one of the cornerstones in the treatment of arterial hypertension (AH). Current American and European guidelines recommend people to ingest... (Review)
Review
Dietary modification is one of the cornerstones in the treatment of arterial hypertension (AH). Current American and European guidelines recommend people to ingest fruit, vegetables, whole grains, and low‑fat dairy products as well as to decrease the consumption of red meat, sugar, and trans fats. This review aimed to summarize available evidence on dietary patterns associated with lower blood pressure (BP). Research has shown that the Dietary Approach to Stop Hypertension (DASH) diet can lower BP equally effectively or even more significantly than some antihypertensive drugs. The Mediterranean diet also leads to a considerable reduction in BP. Vegans and vegetarians have been shown to have a lower prevalence of AH than omnivores. Caloric restriction may decrease BP in normotensive, prehypertensive, and hypertensive populations. Blood pressure can also be lowered by certain nutraceuticals (such as beetroot juice, magnesium, vitamin C, catechin‑rich beverages, or soy isoflavones). Diet effects on BP are mediated by body weight loss, amelioration of inflammation, increased insulin sensitivity, and antihypertensive properties of some individual nutrients. There is robust evidence that vegetarian and vegan diets have the ability to reduce BP. The presence of the so-called floor effect makes these diets usable in normo- and prehypertensive people at high risk of developing AH. However, the dietary and nutraceutical approach to BP lowering cannot substitute drug treatment when the latter is needed.
Topics: Antihypertensive Agents; Blood Pressure; Diet; Dietary Supplements; Humans; Hypertension
PubMed: 32631027
DOI: 10.33963/KP.15468 -
Nutrients Mar 2021Despite being a focal issue to patients, the effect of diet on adult inflammatory bowel disease (IBD) remains underexplored with limited guidance. While promising... (Review)
Review
Despite being a focal issue to patients, the effect of diet on adult inflammatory bowel disease (IBD) remains underexplored with limited guidance. While promising clinical trials are currently underway, there is a need for further evidence-based recommendations. As such, we summarize the current evidence on various diets used in the treatment of IBD and also explore the potential applications of dietary data from related immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis and psoriasis, to provide additional information to inform IBD providers. To date, there have been multiple diets investigated as adjunctive therapy in IBD, but many associated studies are small, non-randomized, and not controlled. Mediterranean, vegetarian/vegan, and reduced-calorie/fasting diets have been studied and have shown some positive results in other IMIDs, which may suggest potential applicability to those with IBD, but larger, well-designed clinical trials are needed for further guidance. Gluten-free and low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP)diets do not appear to have an impact on IBD disease activity, but low FODMAP may potentially be helpful for those with concurrent functional gastrointestinal symptoms. Specific carbohydrate diets have been mainly assessed in children but show some potential in small adult studies.
Topics: Arthritis, Rheumatoid; Caloric Restriction; Diet; Diet, Carbohydrate-Restricted; Diet, Gluten-Free; Diet, High-Protein Low-Carbohydrate; Diet, Mediterranean; Diet, Paleolithic; Diet, Vegan; Diet, Vegetarian; Fasting; Humans; Inflammatory Bowel Diseases; Psoriasis
PubMed: 33801883
DOI: 10.3390/nu13030890 -
Nutrients Feb 2022This interventional study examined the effect of a four-week vegan diet (Veg) during a four-week high-intensity functional training (HIFT) on performance, training... (Randomized Controlled Trial)
Randomized Controlled Trial
This interventional study examined the effect of a four-week vegan diet (Veg) during a four-week high-intensity functional training (HIFT) on performance, training results and blood biochemical indices in female ( = 12) and male ( = 8) moderate-trained CrossFit participants. The whole study group performed the maximum number of repetitions with a load of 70% one repetition-maximum (1RM) and a modified Fight Gone Bad (FGB) test before and after a dietary intervention (the group was divided to follow a Veg or a traditional mixed diet (Mix)) in a randomised and parallel design. Pre-exercise resting blood samples were also analysed. There was a significant improvement in the number of repetitions performed at a load corresponding to 70% of 1RM in the classic squat in the Mix group ( < 0.001), and in the classic deadlift in the Veg group ( = 0.014). Furthermore, there was a significant improvement in the results of the FGB performance test after a Mix. Moreover, an improvement in some exercises in the modified FGB test (Wall Ball after the Veg and the Mix, and rowing after the Mix) was also observed. However, differences between the Mix and the Veg groups were not clinically relevant. In conclusion, the short-term study conducted here indicated that a Veg in HIFT training positively affects strength endurance in the classic deadlift but is unlikely to be more beneficial in improving performance than a Mix.
Topics: Diet, Vegan; Exercise; Female; Humans; Male; Muscle Strength; Muscle, Skeletal; Resistance Training
PubMed: 35215544
DOI: 10.3390/nu14040894 -
Nutrients May 2021There is a lack of data on associations between modern vegetarian and vegan diets and health among children and adolescents. The aim of the Vechi Youth Study was to...
There is a lack of data on associations between modern vegetarian and vegan diets and health among children and adolescents. The aim of the Vechi Youth Study was to cross-sectionally examine anthropometry, dietary intakes and nutritional status in a sample of 149 vegetarian, 115 vegan and 137 omnivore children and adolescents (6-18 years old, mean age: 12.7 ± 3.9 years). Group differences of dietary intake (calculated from three-day dietary records), nutrient biomarker and blood lipid concentrations were assessed using an analysis of covariance, adjusted for sex, age and other covariates. The total energy intake did not differ significantly between groups, but intake of carbohydrates was higher among vegetarians and vegans than among omnivores ( = 0.0002, respectively). The median protein intake exceeded 0.9 g/kg body weight/day in all diet groups and was lowest among vegetarians ( < 0.02). There was no significant difference of haemoglobin, vitamin B2, 25-OH vitamin D3, HDL-C and triglycerides blood concentrations between diet groups. Vegan participants had higher folate concentrations than vegetarian participants ( = 0.0053). Ferritin concentration was significantly higher in omnivores than in vegetarians ( = 0.0134) and vegans ( = 0.0404). Vegetarians had lower concentrations of holotranscobalamin ( = 0.0042) and higher concentrations of methylmalonic acid ( = 0.0253) than omnivores. Vegans had the lowest non-HDL-C and LDL-C concentrations in comparison to vegetarians ( = 0.0053 and = 0.0041) and omnivores ( = 0.0010 and = 0.0010). A high prevalence (>30%) of 25-OH vitamin D3 and vitamin B2 concentrations below reference values were found irrespective of the diet group. In conclusion, the Vechi Youth Study did not indicate specific nutritional risks among vegetarian and vegan children and adolescents compared to omnivores.
Topics: Adolescent; Biomarkers; Child; Diet; Diet Records; Diet, Vegan; Diet, Vegetarian; Eating; Feeding Behavior; Female; Germany; Humans; Lipids; Male; Nutrients; Nutritional Requirements; Nutritional Status
PubMed: 34069944
DOI: 10.3390/nu13051707 -
Nutrients Apr 2020Unhealthy diet is a significant risk factor for cardiovascular diseases (CVD). Therefore, this umbrella review aims to comprehensively review the effects of dietary... (Review)
Review
Unhealthy diet is a significant risk factor for cardiovascular diseases (CVD). Therefore, this umbrella review aims to comprehensively review the effects of dietary factors, including dietary patterns, food groups, and nutrients on CVD risks. Medline and Scopus databases were searched through March 2020. Systematic reviews with meta-analyses (SRMA) of randomized controlled trials (RCTs) or observational studies measuring the effects of dietary factors on CVD risks were eligible. Fifty-four SRMAs, including 35 SRMAs of observational studies, 10 SRMAs of RCTs, and 9 SRMAs of combined RCT and observational studies, were included for review. Findings from the SRMAs of RCTs suggest the significant benefit of Mediterranean and high-quality diets for lowering CVD risk, with pooled risk ratios (RRs) ranging from 0.55 (95%CI: 0.39-0.76) to 0.64 (95%CI: 0.53-0.79) and 0.70 (95%CI: 0.57-0.87), respectively. For food nutrients, two SRMAs of RCTs found that high intake of n-3 polyunsaturated fatty acid (PUFA) significantly reduced CVD risks, with pooled RRs ranging from 0.89 (95%CI: 0.82, 0.98) to 0.90 (95%CI: 0.85-0.96), while evidence of efficacy of n-6 PUFA and combined n-3 and n-6 PUFA were inconsistent. Moreover, results from the SRMAs of RCTs did not find a significant benefit of a low-salt diet and low total fat intake for CVD prevention. For food groups, results from the SRMAs of cohort studies suggest that high intakes of legumes, nuts, and chocolate, as well as a vegetarian diet significantly reduced the risk of coronary heart disease, with pooled RRs of 0.90 (95%CI: 0.84-0.97), 0.68 (95%CI: 0.59-0.78), 0.90 (95%CI: 0.82-0.97), and 0.71 (95%CI: 0.57-0.87), respectively. Healthy dietary patterns had a significant benefit for CVD prevention. With the substitutional and synergistic interactions between different food groups and nutrients, dietary recommendations for CVD prevention should be focused more on healthy dietary patterns than single food groups or nutrients.
Topics: Cardiovascular Diseases; Chocolate; Diet, Fat-Restricted; Diet, Healthy; Diet, Mediterranean; Diet, Sodium-Restricted; Diet, Vegan; Fabaceae; Fatty Acids, Omega-3; Humans; Meta-Analysis as Topic; Nuts; Observational Studies as Topic; Randomized Controlled Trials as Topic; Risk Factors; Systematic Reviews as Topic
PubMed: 32326404
DOI: 10.3390/nu12041088