Vegetarian, vegan diets and multiple health outcomes: A systematic review with meta-analysis of observational studies

  title={Vegetarian, vegan diets and multiple health outcomes: A systematic review with meta-analysis of observational studies},
  author={Monica Dinu and Rosanna Abbate and Gian Franco Gensini and Alessandro Casini and Francesco Sofi},
  journal={Critical Reviews in Food Science and Nutrition},
  pages={3640 - 3649}
BACKGROUND Beneficial effects of vegetarian and vegan diets on health outcomes have been supposed in previous studies. [] Key MethodMETHODS A comprehensive search of Medline, EMBASE, Scopus, The Cochrane Library, and Google Scholar was conducted. RESULTS Eighty-six cross-sectional and 10 cohort prospective studies were included.
Vegetarianism and veganism compared with mental health and cognitive outcomes: a systematic review and meta-analysis.
A meta-analysis found that vegan or vegetarian diets were related to a higher risk of depression and lower anxiety scores, but no differences for other outcomes were found.
A Systematic Review of the Association Between Vegan Diets and Risk of Cardiovascular Disease
Among the Western populations studied, evidence weakly demonstrates associations between vegan diets and risk of CVDs, with the direction of associations varying with the specific CVD outcome tested.
The Impact of Vegan Diet in the Prevention and Treatment of Type 2 Diabetes: A Systematic Review
It is found that a vegan diet is associated with lower T2D prevalence or incidence and in T1D patients decreases high glucose values and improves glucose homeostasis, as reported from the majority of included studies.
Relation of Vegetarian Dietary Patterns With Major Cardiovascular Outcomes: A Systematic Review and Meta-Analysis of Prospective Cohort Studies
Very low-quality evidence indicates that vegetarian dietary patterns are associated with reductions in CHD mortality and incidence but not with CVD and stroke mortality in individuals with and without diabetes.
The effect of vegetarian diets on iron status in adults: A systematic review and meta-analysis
It is recommended that not only vegetarians but also non-vegetarians should regularly control their iron status and improve their diet regarding the content and bioavailability of iron by consuming more plants and less meat.
Adherence to the vegetarian diet may increase the risk of depression: a systematic review and meta-analysis of observational studies.
Vegetarian diet significantly increased depression risk; however, the findings were not robust, and more studies are required to investigate the vegetarian diet and depression association.
Plant-based diets and risk of disease mortality: a systematic review and meta-analysis of cohort studies.
The findings show the potential protective role of PBDs against chronic disease mortality, and there was an inverse association between healthy plant-based and vegetarian diets and the risk of all-cause mortality.
Vegetarianism and breast, colorectal and prostate cancer risk: an overview and meta‐analysis of cohort studies
A summary of the existing evidence from cohort studies on vegetarian diets showed that complete exclusion of any source of protein from the diet is not associated with further benefits for human health.
The Association of Plant-Based Diet With Cardiovascular Disease and Mortality: A Meta-Analysis and Systematic Review of Prospect Cohort Studies
A comprehensive study examines the effects of a plant-based diet on major clinical endpoints using more holistic PDIs and highlights the favorable role of healthful plant- based foods in reducing cardiovascular mortality and CVD.


Cardiovascular Disease Mortality and Cancer Incidence in Vegetarians: A Meta-Analysis and Systematic Review
It is suggested that vegetarians have a significantly lower ischemic heart disease mortality and overall cancer incidence than nonvegetarians.
Beyond Meatless, the Health Effects of Vegan Diets: Findings from the Adventist Cohorts
Vegetarians, those who avoid meat, and vegans, additionally avoiding dairy and eggs, represent 5% and 2%, respectively, of the US population. The aim of this review is to assess the effects of
Lifestyle Determinants and Mortality in German Vegetarians and Health-Conscious Persons: Results of a 21-Year Follow-up
Low prevalence of smoking and moderate or high level of physical activity but not strictly vegetarian diet was associated with reduced overall mortality, and the nonsignificant reduction in mortality from ischemic heart diseases in vegetarians compared with health-conscious persons could be explained in part by avoidance of meat intake.
Vegetarian Diets and the Incidence of Cancer in a Low-risk Population
Vegan diet seems to confer lower risk for overall and female-specific cancer than other dietary patterns and the lacto-ovo-vegetarian diets seem to confer protection from cancers of the gastrointestinal tract.
Vegetarian diets: what do we know of their effects on common chronic diseases?
  • G. Fraser
  • Medicine
    The American journal of clinical nutrition
  • 2009
It is probable that using the label "vegetarian" as a dietary category is too broad and that understanding will be served well by dividing vegetarians into more descriptive subtypes, and different types of vegetarians may not experience the same effects on health.
Mortality in British vegetarians: results from the European Prospective Investigation into Cancer and Nutrition (EPIC-Oxford).
Mortality from circulatory diseases and all causes is not significantly different between vegetarians and meat eaters, but the study is not large enough to exclude small or moderate differences for specific causes of death, and more research on this topic is required.
Vegetarian dietary patterns and mortality in Adventist Health Study 2.
Vegetarian diets are associated with lower all-cause mortality and with some reductions in cause-specific mortality, and appeared to be more robust in males.
Vegetarian dietary patterns and the risk of colorectal cancers.
Vegetarian diets are associated with an overall lower incidence of colorectal cancers, and pescovegetarians in particular have a much lower risk compared with nonvegetarians.
Mortality in vegetarians and nonvegetarians: detailed findings from a collaborative analysis of 5 prospective studies.
Mortality from ischemic heart disease among vegetarians was 24% lower in vegetarians than in nonvegetarians, and was greater at younger ages and was restricted to those who had followed their current diet for >5 y.