Plant-Based & Vegan Diets
Built around whole plant foods, with different rules for how strict to go.
How It Works
"Plant-based" and "vegan" get used interchangeably, but they're not the same thing. Vegan is the strict version: it excludes all animal-derived foods and ingredients — meat, poultry, seafood, dairy, eggs, honey, and often gelatin or other animal-derived additives. Plant-based is looser, spectrum language — it emphasizes minimizing animal products and maximizing whole plant foods (fruits, vegetables, legumes, whole grains, nuts, seeds) without requiring full exclusion, so someone "eating plant-based" may still occasionally eat meat, dairy, or eggs. Vegan is a strict subset of plant-based, not a synonym for it.
The Research
Associated with lower BMI, lower rates of type 2 diabetes and heart disease, and lower all-cause mortality in large cohort studies — with the important caveat that the benefit is concentrated in healthful plant-based patterns (whole grains, produce, legumes, nuts) rather than "unhealthful" ones built on refined carbs and sugar.
Cohort study: Orlich MJ, Singh PN, Sabaté J, et al. "Vegetarian Dietary Patterns and Mortality in Adventist Health Study 2," JAMA Internal Medicine, 2013. Following 73,308 Seventh-day Adventists, vegetarian diets — including a vegan subgroup — were associated with lower all-cause and cardiovascular mortality than non-vegetarian diets.Read the cohort study →
Additional research:
Qian F, Liu G, Hu FB, Bhupathiraju SN, Sun Q. "Association Between Plant-Based Dietary Patterns and Risk of Type 2 Diabetes: A Systematic Review and Meta-analysis," JAMA Internal Medicine, 2019. Greater adherence to plant-based patterns — especially "healthful" ones — was associated with significantly lower type 2 diabetes risk; "unhealthful" plant-based patterns were not protective.
Read the meta-analysis →
Quek J, Lim G, Lim WH, et al. "The Association of Plant-Based Diet With Cardiovascular Disease and Mortality: A Meta-Analysis and Systematic Review of Prospective Cohort Studies," Frontiers in Cardiovascular Medicine, 2021. Across 13 cohorts (~410,000 people), higher plant-based adherence was linked to roughly 8–10% lower cardiovascular disease incidence and mortality — again, concentrated in healthful patterns.
Read the meta-analysis →
Nutrient-adequacy caveat: Melina V, Craig W, Levin S. "Position of the Academy of Nutrition and Dietetics: Vegetarian Diets," Journal of the Academy of Nutrition and Dietetics, 2016. States that well-planned vegetarian and vegan diets are nutritionally adequate across life stages — but explicitly flags vitamin B12 (absent from plant foods entirely), iron and zinc (lower bioavailability from non-heme sources), long-chain omega-3s, vitamin D, calcium, and iodine as nutrients that need deliberate attention, particularly on a fully vegan diet.
Read the position paper →
Food Examples
Protein: lentils, chickpeas, black beans, tofu, tempeh, seitan, edamame.
Whole grains: quinoa, brown rice, oats, farro.
Nuts & seeds: almonds, walnuts, chia, flax, hemp seeds.
B12 sources for strict vegans: fortified nutritional yeast, fortified plant milks and
cereals, or a B12 supplement — per the Academy of Nutrition and Dietetics, this is the one nutrient
that has no reliable unfortified plant source, so it isn't optional for a fully vegan diet.
A Sample Day
Breakfast: oats with fortified soy milk, chia seeds, and berries.
Lunch: lentil soup with whole-grain bread and a tahini-dressed salad.
Snack: hummus with vegetables, or a handful of almonds.
Dinner: tofu-and-vegetable stir-fry over brown rice with edamame.
Include a B12-fortified food or supplement daily if eating strictly vegan.
Who It Might Suit
Tends to suit people motivated by environmental or ethical concerns, or by the cardiometabolic risk reduction the research above points to, and who are willing to plan meals rather than eat on autopilot. The Academy of Nutrition and Dietetics' position is that these diets are appropriate for athletes and all life stages "when appropriately planned" — that qualifier matters. Without deliberate attention to B12, iron, omega-3s, vitamin D, and calcium, or for people with very high calorie and protein needs, real gaps can occur, especially on a fully vegan diet with less margin for error than a looser plant-based pattern that still includes some animal foods.