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Nutrients Aug 2022During the complementary feeding period, any nutritional deficiencies may negatively impact infant growth and neurodevelopment. A healthy diet containing all essential... (Review)
Review
During the complementary feeding period, any nutritional deficiencies may negatively impact infant growth and neurodevelopment. A healthy diet containing all essential nutrients is strongly recommended by the WHO during infancy. Because vegetarian diets are becoming increasingly popular in many industrialized countries, some parents ask the pediatrician for a vegetarian diet, partially or entirely free of animal-source foods, for their children from an early age. This systematic review aims to evaluate the evidence on how vegetarian complementary feeding impacts infant growth, neurodevelopment, risk of wasted and/or stunted growth, overweight and obesity. The SR was registered with PROSPERO 2021 (CRD 42021273592). A comprehensive search strategy was adopted to search and find all relevant studies. For ethical reasons, there are no interventional studies assessing the impact of non-supplemented vegetarian/vegan diets on the physical and neurocognitive development of children, but there are numerous studies that have analyzed the effects of dietary deficiencies on individual nutrients. Based on current evidence, vegetarian and vegan diets during the complementary feeding period have not been shown to be safe, and the current best evidence suggests that the risk of critical micronutrient deficiencies or insufficiencies and growth retardation is high: they may result in significantly different outcomes in neuropsychological development and growth when compared with a healthy omnivorous diet such as the Mediterranean Diet. There are also no data documenting the protective effect of vegetarian or vegan diets against communicable diseases in children aged 6 months to 2-3 years.
Topics: Animals; Diet, Vegan; Diet, Vegetarian; Eating; Humans; Infant; Infant Nutritional Physiological Phenomena; Malnutrition; Vegetarians
PubMed: 36079848
DOI: 10.3390/nu14173591 -
Nutrition Bulletin Mar 2022Recent evidence suggests that vegetarian and vegan diets may increase the risk and symptoms of depression, a mental health condition affecting 350 million people... (Review)
Review
Recent evidence suggests that vegetarian and vegan diets may increase the risk and symptoms of depression, a mental health condition affecting 350 million people globally. We aimed to systematically review the literature on the associations between vegetarian and/or vegan diets and the risk or symptoms of depression using evidence from both observational and intervention studies. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with pre-specification of all methods. A systematic search for relevant papers was performed on Medline and Embase, Web of Science and the Cochrane Library for cohort, case-control, cross-sectional studies or randomised controlled trials examining associations between a vegetarian or vegan diet and depression in adults. Three independent reviewers extracted data and assessed risk of bias using the National Heart, Lung, and Blood Institute of the National Institutes of Health for Quality Assessment of Observational Cohort and Cross-Sectional Studies and Controlled Studies. Evidence was tabulated according to the type of diet analysed as vegetarian, vegan or both and narratively synthesised. A total of 23 studies (18 cross-sectional, three prospective cohort and two randomised controlled trials) with 25 study outcomes were eligible for inclusion in this review. Conflicting evidence was found on the association between vegetarian or vegan diets and depression. Eleven (44%) of the outcomes indicated that vegetarian and vegan diets were associated with higher rates of depression, while seven (28%) outcomes revealed beneficial effects of the diets on depression. Seven (28%) outcomes found no association between vegetarian and vegan diets and depression, although two of these studies found a higher risk of depression in some groups. The quality of evidence was rated as good for four of the studies with the remaining 19 studies rated as fair. The evidence on the effect of vegetarian and vegan diets on depression is contradictory, possibly due to the heterogeneity of the studies analysed. Further research, including longitudinal and intervention studies, is required to resolve this observation.
Topics: Adult; Cross-Sectional Studies; Depression; Diet, Vegan; Diet, Vegetarian; Humans; Prospective Studies; Randomized Controlled Trials as Topic; United States; Vegetarians
PubMed: 36045075
DOI: 10.1111/nbu.12540 -
European Journal of Nutrition Feb 2023Vegetarian diets have been associated with reduced risk of ischemic heart disease (IHD). However, results regarding cardiovascular disease (CVD) overall and stroke are... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Vegetarian diets have been associated with reduced risk of ischemic heart disease (IHD). However, results regarding cardiovascular disease (CVD) overall and stroke are less clear. We conducted a systematic review and meta-analysis of prospective cohort studies on CVD, IHD and stroke risk among vegetarians or vegans versus nonvegetarians to clarify these associations.
METHODS
PubMed and Ovid Embase databases were searched through August 12, 2021. Prospective cohort studies reporting adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) for incidence or mortality from CVD, IHD and stroke, comparing vegetarians and vegans to nonvegetarians were included. Risk of bias (RoB) was assessed using ROBINS-I and the strength of evidence was assessed using World Cancer Research Fund (WCRF) criteria. Summary RRs (95% CIs) were estimated using a random effects model.
RESULTS
Thirteen cohort studies (844,175 participants, 115,392 CVD, 30,377 IHD, and 14,419 stroke cases) were included. The summary RR for vegetarians vs. nonvegetarians was 0.85 (95% CI: 0.79-0.92, I = 68%, n = 8) for CVD, 0.79 (95% CI: 0.71-0.88, I = 67%, n = 8) for IHD, 0.90 (95% CI: 0.77-1.05, I = 61%, n = 12) for total stroke, and for vegans vs. nonvegetarians was 0.82 (95% CI: 0.68-1.00, I = 0%, n = 6) for IHD. RoB was moderate (n = 8) to serious (n = 5). The associations between vegetarian diets and CVD and IHD were considered probably causal using WCRF criteria.
CONCLUSIONS
Vegetarian diets are associated with reduced risk of CVD and IHD, but not stroke, but further studies are needed on stroke. These findings should be considered in dietary guidelines.
REVIEW REGISTRATION
No review protocol registered.
Topics: Humans; Cardiovascular Diseases; Diet, Vegan; Prospective Studies; Myocardial Ischemia; Diet, Vegetarian; Vegetarians; Cohort Studies
PubMed: 36030329
DOI: 10.1007/s00394-022-02942-8 -
Diabetology & Metabolic Syndrome Aug 2022A vegan diet has benefits on weight reduction and on the parameters of glucose and lipid metabolism. This meta-analysis aimed to investigate the efficacy of plant-based...
BACKGROUND
A vegan diet has benefits on weight reduction and on the parameters of glucose and lipid metabolism. This meta-analysis aimed to investigate the efficacy of plant-based diets on insulin resistance and blood lipids in patients with obesity.
METHODS
PubMed, Embase, and the Cochrane Library were searched for available papers published up to March 2021. The primary outcome was insulin resistance which was assessed by Homeostasis Model Assessment Insulin Resistance (HOMA-IR), other metabolic parameters measures including the pre/post-diet changes in triglycerides, HDL-cholesterol, total cholesterol, LDL-cholesterol. All analyses were performed using the random-effects model.
RESULTS
Six studies (seven datasets) were included. Compared with baseline, the plant-based diet improved the HOMA-IR (SMD = 1.64, 95%CI 0.95, 2.33; I = 91.8%, P < 0.001), total cholesterol (SMD = 2.51, 95% CI 0.88, 4.13; I = 98.0%, P < 0.001), HDL-cholesterol (SMD = 1.55, 95% CI 0.66, 2.44; I = 92.0%, P < 0.001), and LDL-cholesterol (SMD = 2.50, 95% CI 1.30, 3.70; I = 94.4%, P < 0.001), but not the triglycerides (SMD = - 0.62, 95% CI - 1.92, 0.68; I = 97.8%, P < 0.001). The sensitivity analyses showed that the results were robust.
CONCLUSIONS
In obese individuals with insulin resistance, a vegan diet improves insulin resistance and dyslipidemia, except for triglycerides.
PubMed: 35964120
DOI: 10.1186/s13098-022-00879-w -
Prostate Cancer and Prostatic Diseases Sep 2022Plant-based diets are increasingly popular and have many well-established benefits for health and environmental sustainability. Our objective was to perform a systematic... (Review)
Review
BACKGROUND
Plant-based diets are increasingly popular and have many well-established benefits for health and environmental sustainability. Our objective was to perform a systematic review of plant-based diets and prostate cancer.
METHODS
We performed a systematic database and citation search in February 2022. Studies were included if they reported primary data on plant-based dietary patterns (i.e., vegan, vegetarian, plant-based) and incidence among at-risk men for prostate cancer, or oncologic, general health/nutrition, or quality of life outcomes among patients with prostate cancer or caregivers.
RESULTS
A total of 32 publications were eligible for the qualitative synthesis, representing 5 interventional and 11 observational studies. Interventional studies primarily focused on lifestyle modification including plant-based diets for men on active surveillance for localized prostate cancer or with biochemical recurrence after treatment, showing improvements in short-term oncologic outcomes alongside improvements in general health and nutrition. Observational studies primarily focused on prostate cancer risk, showing either protective or null associations for plant-based dietary patterns. Studies of the vegan diet consistently showed favorable associations with risk and/or outcomes. Gaps in the current literature include impact for long-term disease-specific outcomes.
CONCLUSIONS
Interventional studies showed generally favorable results of lifestyle modifications incorporating a plant-based diet with prostate cancer outcomes as well as improvements in nutrition and general health. Observational studies demonstrated either a lower risk of prostate cancer or no significant difference. These results are encouraging in light of the many benefits of plant-based diets for overall health, as well as environmental sustainability and animal welfare.
Topics: Diet; Diet, Vegan; Humans; Incidence; Life Style; Male; Prostatic Neoplasms; Quality of Life
PubMed: 35790788
DOI: 10.1038/s41391-022-00553-2 -
Frontiers in Psychology 2022In recent years, and in the current climate crisis, the interest in veganism and sustainable diet/lifestyle has increased. This growing interest can also be seen within...
In recent years, and in the current climate crisis, the interest in veganism and sustainable diet/lifestyle has increased. This growing interest can also be seen within academia. Therefore, we set out to systematically document and organize the social psychological literature on veganism and vegan identity to identify where the field currently is, and what we need to do next. Following PRISMA guidelines we identified a data set of 26 academic papers published between 2010 and 2021. Through a thematic analysis of the data, we created four categories of study focus and content: (1) vegans as a disadvantaged/stigmatized group, (2) the role of ideology in negative attitudes toward vegans, (3) the role of moral and ethical beliefs in changing or sustaining dietary preferences, and (4) veganism as a social movement and vegan activism. Our analysis emphasizes issues with merging all non-meat eaters, reduction of veganism into dietary or lifestyle choices neglecting the politicized content and movement, lack of processes underlying emergence and endurance of veganism, and decontextualization of vegan identity. What is needed is a more fine-grained exploration that addresses the identified issues to account for the content of vegan identity. This would expand, for example, the motives literature to include and emphasize intersectionality in a vegan identity context. Specifically, to facilitate a more sustainable lifestyle, the content of social dimensions needs to be qualitatively explored.
PubMed: 35756214
DOI: 10.3389/fpsyg.2022.848434 -
Eating and Weight Disorders : EWD Oct 2022Meat avoidance has long been thought to be related to eating psychopathology; however, research does not necessarily support this notion. Furthermore, commonly used... (Review)
Review
PURPOSE
Meat avoidance has long been thought to be related to eating psychopathology; however, research does not necessarily support this notion. Furthermore, commonly used eating disorder scales may be picking up on normal meat-avoiding behaviours in vegetarians and vegans. As such, we systematically reviewed the association between vegetarianism, veganism, and disordered eating, and reviewed the psychometric properties of eating disorder scales for use in these populations.
METHODS
We searched electronic databases MEDLINE, PsychINFO, and CINAHL for literature published until June 2021.
RESULTS
Forty-eight studies met eligibility criteria, with no consensus as to whether meat avoidance was associated with higher rates of disordered eating. Most studies reported a significant positive association with both vegetarianism and veganism, and orthorexia nervosa. Six studies provided evidence for the use of eating disorder measures in vegetarians and vegans, reporting poor psychometric fit among all scales.
CONCLUSION
This systematic review highlights the extent to which vegetarians and vegans have been highly understudied, with limited research suggesting higher levels of orthorexia nervosa behaviours in vegetarians and vegans. Furthermore, our results provide tentative evidence that the factorial validity of commonly used eating disorder scales, such as the EDE-Q, may be poor in vegans.
LEVEL OF EVIDENCE
Level I, systematic review.
Topics: Diet, Vegan; Feeding and Eating Disorders; Humans; Meat; Vegans; Vegetarians
PubMed: 35729472
DOI: 10.1007/s40519-022-01428-0 -
Frontiers in Public Health 2022Diets containing red or processed meat are associated with a growing risk of digestive system cancers. Whether a plant-based diet is protective against cancer needs a... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVES
Diets containing red or processed meat are associated with a growing risk of digestive system cancers. Whether a plant-based diet is protective against cancer needs a high level of statistical evidence.
METHODS
We performed a meta-analysis of five English databases, including PubMed, Medline, Embase, Web of Science databases, and Scopus, on October 24, 2021 to identify published papers. Cohort studies or case-control studies that reported a relationship between plant-based diets and cancers of the digestive system were included. Summary effect-size estimates are expressed as Risk ratios (RRs) or Odds ratios (ORs) with 95% confidence intervals and were evaluated using random-effect models. The inconsistency index (I) and τ (Tau) index were used to quantify the magnitude of heterogeneity derived from the random-effects Mantel-Haenszel model.
RESULTS
The same results were found in cohort (adjusted RR = 0.82, 95% CI: 0.78-0.86, < 0.001, = 46.4%, Tau = 0.017) and case-control (adjusted OR = 0.70, 95% CI: 0.64-0.77, < 0.001, = 83.8%, Tau = 0.160) studies. The overall analysis concluded that plant-based diets played a protective role in the risk of digestive system neoplasms. Subgroup analyses demonstrated that the plant-based diets reduced the risk of cancers, especially pancreatic (adjusted RR = 0.71, 95% CI: 0.59-0.86, < 0.001, = 55.1%, Tau = 0.028), colorectal (adjusted RR = 0.76, 95% CI: 0.69-0.83, < 0.001, = 53.4%, Tau = 0.023), rectal (adjusted RR = 0.84, 95% CI: 0.78-0.91, < 0.001, = 1.6%, Tau = 0.005) and colon (adjusted RR = 0.88, 95% CI: 0.82-0.95, < 0.001, = 0.0%, Tau = 0.000) cancers, in cohort studies. The correlation between vegan and other plant-based diets was compared using Z-tests, and the results showed no difference.
CONCLUSIONS
Plant-based diets were protective against cancers of the digestive system, with no significant differences between different types of cancer.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022322276, Identifier: CRD42022322276.
Topics: Case-Control Studies; Cohort Studies; Diet; Diet, Vegetarian; Digestive System Neoplasms; Humans
PubMed: 35719615
DOI: 10.3389/fpubh.2022.892153 -
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 -
Nutrients Dec 2021Health authorities increasingly recommend a more plant-based diet, rich in fruits, vegetables, pulses, whole grains and nuts, low in red meat and moderate in dairy,...
Health authorities increasingly recommend a more plant-based diet, rich in fruits, vegetables, pulses, whole grains and nuts, low in red meat and moderate in dairy, eggs, poultry and fish which will be beneficial for both health and the environment. A systematic review of observational and intervention studies published between 2000 and January 2020 was conducted to assess nutrient intake and status in adult populations consuming plant-based diets (mainly vegetarian and vegan) with that of meat-eaters. Mean intake of nutrients were calculated and benchmarked to dietary reference values. For micronutrient status, mean concentrations of biomarkers were calculated and compared across diet groups. A total of 141 studies were included, mostly from Europe, South/East Asia, and North America. Protein intake was lower in people following plant-based diets compared to meat-eaters, but well within recommended intake levels. While fiber, polyunsaturated fatty acids (PUFA), folate, vitamin C, E and magnesium intake was higher, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake was lower in vegetarians and vegans as compared to meat-eaters. Intake and status of vitamin B12, vitamin D, iron, zinc, iodine, calcium and bone turnover markers were generally lower in plant-based dietary patterns compared to meat-eaters. Vegans had the lowest vitamin B12, calcium and iodine intake, and also lower iodine status and lower bone mineral density. Meat-eaters were at risk of inadequate intakes of fiber, PUFA, α-linolenic acid (ALA), folate, vitamin D, E, calcium and magnesium. There were nutrient inadequacies across all dietary patterns, including vegan, vegetarian and meat-based diets. As plant-based diets are generally better for health and the environment, public health strategies should facilitate the transition to a balanced diet with more diverse nutrient-dense plant foods through consumer education, food fortification and possibly supplementation.
Topics: Adult; Aged; Aged, 80 and over; Animals; Asia; Diet, Vegan; Diet, Vegetarian; Dietary Fiber; Dietary Proteins; Eating; Energy Intake; Europe; Feeding Behavior; Female; Humans; Male; Meat; Micronutrients; Middle Aged; North America; Nutrients; Nutritional Status; Vitamins
PubMed: 35010904
DOI: 10.3390/nu14010029