Is a vegan diet good for you
Executive summary
A growing body of research links well-planned vegan and other plant-based diets to lower body weight, reduced cardiometabolic risks and lower risks of some cancers — with studies reporting modest reductions in mortality and disease incidence when animal products are replaced by whole plant foods [1] [2] [3]. At the same time, peer‑reviewed reviews and clinical guidance warn that vegan diets can produce micronutrient shortfalls (notably B12, iodine, vitamin D) and may increase fracture risk unless carefully managed [4] [3] [5].
1. Evidence of benefit: lower weight and cardiometabolic risk
Multiple meta-analyses and umbrella reviews report that vegan and broader plant-based diets reduce body weight (about −2.5 kg in pooled RCTs), lower LDL cholesterol and improve glycemic control — effects that translate into lower risks of type 2 diabetes, heart disease and some cancers in large observational cohorts [3] [1] [2]. Major reviews over two decades find consistent statistical associations between vegetarian/vegan patterns and favorable cardiometabolic markers such as blood pressure, BMI and blood sugar management [1].
2. Institutional endorsement: “appropriately planned” is the key phrase
Professional bodies now say vegan patterns can be nutritionally adequate if planned. The Academy of Nutrition and Dietetics’ 2025 position paper states that appropriately planned vegetarian and vegan diets can offer long‑term health benefits and be nutritionally adequate for adults, and recommends RDNs help tailor diets to avoid nutrient gaps [6] [7].
3. The counterpoint: nutrient shortfalls and other risks
Systematic reviews and clinical summaries flag consistent risks: vitamin B12 is absent from unfortified vegan diets and deficiencies can harm neurological health; iodine, vitamin D and sometimes iron, calcium and omega‑3 status require attention or supplementation [5] [8]. An umbrella review also found an association between vegan diets and higher fracture risk in some studies, indicating bone health can suffer without careful planning or supplementation [3] [4].
4. What the real‑world studies say about mortality and disease
Large cohort work such as Adventist Health Study‑2 and pooled meta‑analyses show lower overall and disease‑specific mortality for vegetarians/vegans in many analyses — e.g., vegans with up to ~15% lower overall mortality in some reports and estimated reductions in premature mortality from noncommunicable diseases in the high‑teens percent range in modelling studies — but the strength of these associations varies by study design and population [2] [8] [1]. Reviews caution that differences in lifestyle and demographics (exercise, smoking, SES) may explain part of the apparent benefit [4].
5. What “vegan” actually means for health: diet quality matters
Researchers and clinicians emphasize that the health effects depend on food choices: a whole‑food vegan pattern rich in fruits, vegetables, legumes, whole grains and minimally processed foods delivers benefits; a vegan diet high in refined carbs and ultra‑processed meat substitutes may not [1] [9]. Clinical voices remind patients that you can be overweight or malnourished on a vegan diet — quality, not label, determines much of the outcome [10] [9].
6. Practical implications: monitoring and supplementation
Authors and position papers recommend planning: B12 supplementation or fortified foods are essential for vegans, and attention to vitamin D, iodine, calcium and omega‑3s is prudent; dietitians can create culturally appropriate plans that optimize benefits while reducing nutrient inadequacies [5] [6] [7]. Reviews urge clinical monitoring of vulnerable groups (young people, pregnant women, older adults) and long‑term follow‑up to detect deficiencies [4].
7. Wider context and competing priorities: health plus environment
Beyond personal health, some studies highlight environmental co‑benefits: modeled vegan menus reduced diet‑related greenhouse gases and land use substantially while delivering most nutrients, though authors note extra attention is needed for B12, iodine and vitamin D in those models [8] [11]. Advocates may emphasize planetary gains; critics stress individual nutrient risks — both perspectives are present in the literature [8] [4].
8. Bottom line for readers deciding whether to go vegan
A vegan diet can be health‑promoting and reduce risk factors for major chronic diseases when it emphasizes whole plant foods and is planned to cover micronutrients [1] [3] [6]. Available sources do not mention individualized genetic or long‑term cohort effects beyond those already cited; therefore, anyone adopting a vegan diet should consult a registered dietitian or clinician for tailored advice and routine monitoring, especially for B12, bone health markers and vitamin D/iodine status [5] [4].
Limitations: this summary draws only on the provided articles and position papers; heterogeneity of study designs and populations limits precise effect estimates and some sources note residual confounding by lifestyle factors [1] [4].