For most people, going vegan delivers measurable benefits for heart health, diabetes risk, environmental impact, and grocery costs, but it also introduces real nutritional gaps that require planning. Whether it’s “worth it” depends on what you’re optimizing for and how willing you are to manage a few key nutrients. Here’s what the evidence actually shows.
The Heart Health Case Is Strong
One of the clearest wins for a vegan diet is cardiovascular health. A meta-analysis of 30 randomized trials published in the European Heart Journal found that switching to a plant-based diet reduced LDL cholesterol (the kind that clogs arteries) by 10% and total cholesterol by 7% compared to omnivorous diets. That’s a meaningful shift, roughly equivalent to what some people achieve with low-dose statins.
These improvements come largely from eliminating saturated fat found in meat and dairy while increasing fiber intake. The cholesterol reduction alone makes a vegan diet worth considering if heart disease runs in your family or your numbers are trending in the wrong direction.
Diabetes Risk Drops Significantly
The data on type 2 diabetes is striking. In a large study of over 41,000 people, vegans had about 62% lower odds of developing type 2 diabetes compared to non-vegetarians, even after adjusting for body weight and other lifestyle factors. A separate study in the Adventist Health cohort found vegans had roughly half the rate of diabetes compared to meat-eaters. Among Taiwanese Buddhist women past menopause, vegetarians had one-quarter the diabetes rate of omnivores.
The protection isn’t just about being thinner. These studies controlled for BMI, meaning the diet itself appears to improve how the body handles blood sugar, likely through higher fiber intake, lower saturated fat, and better insulin sensitivity.
Longevity Is Less Clear-Cut
If you’re going vegan hoping to live longer, the evidence is more ambiguous. A large U.S. prospective study tracked over 117,000 participants for an average of 18 years. The risk of dying from any cause did not significantly differ between vegans, vegetarians, pescatarians, and omnivores. Vegans actually trended slightly higher in mortality risk, though the result wasn’t statistically significant and the vegan group was small (only 140 people).
This doesn’t mean veganism shortens your life. It means the diet alone isn’t a guaranteed longevity hack. A well-planned vegan diet likely lands you in the same ballpark as any other health-conscious eating pattern. The quality of what you eat matters more than the label you put on it.
The Nutrients You Need to Manage
The biggest practical downside of veganism is that several essential nutrients become harder to get, and ignoring this can cause real problems.
Vitamin B12 is the most critical gap. About 52% of vegans show deficient B12 levels, compared to just 1% of omnivores. B12 is essential for nerve function and red blood cell production, and deficiency can cause fatigue, numbness, and cognitive issues that develop slowly and are easy to miss. There is no reliable plant source of B12, so supplementation isn’t optional.
Iron requires more attention on a vegan diet, though it’s manageable. Your body absorbs about 25% of the iron from animal sources but 17% or less from plants. Overall iron bioavailability drops to 5-12% for plant-based eaters, compared to 14-18% for those eating animal products. Pairing iron-rich foods like lentils and spinach with vitamin C significantly improves absorption, but you’ll need to be deliberate about it.
Protein quality is often overstated as a concern, but it’s worth understanding. Soy protein scores nearly identically to whey and egg on standardized quality measures. Pea protein scores slightly lower, and wheat protein scores about half as well. The practical takeaway: if you eat a variety of protein sources throughout the day, including soy, legumes, and quinoa, you’ll cover your amino acid needs without difficulty. Relying on a single grain as your main protein source is where problems emerge.
The Environmental Impact Is Substantial
If reducing your environmental footprint matters to you, this is where veganism delivers the most dramatic results. A vegan diet produces about 2.1 kg of CO2 equivalents per day, compared to 3.8 kg for a standard omnivorous diet. That’s a 46% reduction in greenhouse gas emissions from food alone.
Water use tells a similar story. Producing one kilogram of protein from livestock requires roughly 67,600 liters of water, compared to about 25,600 liters for plant protein. Beef is the most water-intensive of all, while soy protein is more water-efficient than every animal source tested, including chicken and dairy. If you’re motivated by climate concerns, switching to a vegan diet is one of the single largest changes an individual can make.
It Can Cost Less Than You’d Expect
A common assumption is that vegan eating is expensive, but research published in JAMA Network Open found the opposite. A low-fat vegan diet built around fruits, vegetables, grains, and beans cost about $1.80 less per day than a standard American diet, adding up to more than $650 in annual savings. That’s a 19% reduction in grocery spending.
The caveat is that this applies to whole-food vegan eating. Specialty vegan products like plant-based meats, artisanal nut cheeses, and protein bars can easily push costs above what you’d spend on a conventional diet. The savings come from building meals around dried beans, lentils, rice, oats, frozen vegetables, and tofu, which are among the cheapest foods in any grocery store.
Who Benefits Most
Veganism makes the strongest case for people with elevated cholesterol, a family history of type 2 diabetes, or strong environmental convictions. The heart and metabolic benefits are well-documented and meaningful. The environmental gains are hard to match with any other single lifestyle change.
It makes a weaker case if you’re unwilling to supplement B12, pay attention to iron and protein variety, or cook most of your meals from whole ingredients. A poorly planned vegan diet can leave you deficient in ways that take months or years to notice. It also offers no clear longevity advantage over other health-conscious eating patterns, so if that’s your primary motivation, the evidence doesn’t strongly support the switch.
For many people, the practical middle ground is worth considering: eating predominantly plant-based while occasionally including animal products eliminates most of the nutritional risk while capturing a large share of the health and environmental benefits. Whether you go fully vegan or mostly plant-based, the biggest factor is the quality of your overall diet, not the purity of the label.