Does a vegan diet lower cholesterol?

Yes, and the evidence is unusually clean. In 22 pairs of identical twins, the vegan twin's LDL was 13.9 mg/dL lower than their twin's after eight weeks. Because the design matches genes and upbringing, that result is hard to explain any other way. Calories were not matched, though, so part of it comes from a 1.9 kg weight difference.

Do vegans live longer?

The two big long-term studies disagree, and that is the honest answer, not a dodge. A North American study of Seventh-day Adventists found vegetarians overall had a 12 percent lower death rate, and the vegan result alone was too uncertain to call. A pooled UK study, which compared against health-minded meat eaters, found no difference at all. Both only tracked people who chose their own diets, and neither settles it.

What about the stroke finding?

EPIC-Oxford found vegetarians had 20 percent more strokes overall over 18 years, driven by strokes from bleeding in the brain. That is about 3 more cases per 1,000 people over ten years. It is in the paper's published title, and summaries usually leave it out. Unlike the heart disease benefit in the same paper, it did not shrink when disease risk factors were accounted for. Nobody knows why, and a study that only watches people cannot tell us.

Can I build muscle on it?

Yes, but you have to plan the protein rather than expect it. Plant proteins have less leucine and the body absorbs them a bit less well, so a high target needs beans, soy and protein powder on purpose. The muscle data inside these studies is too thin to quote, which is worth knowing in itself.

Plant-forward10 studies in people cited

Vegan and vegetarian

Q: Is the hip fracture risk real?

It is the biggest warning sign for this diet. After adjustment, vegans had 2.31 times the hip fracture risk, equal to 14.9 more hip fractures per 1,000 people over ten years. Adventist data suggests the extra risk is only in people not taking both calcium and vitamin D, which makes it fixable. Fixing it means actually taking supplements and getting tested, not assuming your food covers it.

Written by Aaron CuhaReviewed Sep 2026

Also called: Plant-based, Plant-exclusive, Vegetarian

Solid trial data on LDL cholesterol and weight, and the best study used 22 pairs of identical twins. The big long-term studies disagree on whether vegans live longer. The two results fans leave out are stroke and hip fractures.

What it actually is

Vegan cuts out all animal foods. Vegetarian cuts out meat and usually fish, but allows dairy and eggs. The difference matters more than it looks. In the data on how long people live, the two diets behave differently, and the strictest version does not have the best numbers.

How its fans say it works

Less saturated fat and no cholesterol in the food lower LDL. Lots of fibre, and big portions with few calories, cut how much you eat without hunger. Skipping processed meat removes something linked to bowel cancer. All three make sense, and the first two can be measured within weeks.

What happened when calories were controlled

Best kind of study available: people ate freely

Both groups ate as much as they wanted. A difference here mixes the diet with how full it kept people and how well they stuck to it.

Almost never, and that is the main catch in this research. The best trials provided food but did not match calories, so part of every result comes from weight loss rather than from the diet itself.

Kahleova 2020 put 244 overweight adults on either a low fat vegan diet or no diet change at all. The vegan group lost 5.9 kg, their insulin resistance score fell by 1.3, and the calories they burned digesting food rose 14.1 percent. This compares a diet against no diet. It shows that a supported diet beats changing nothing. It says nothing about vegan against another real diet.
Barnard 2006 put 99 adults with type 2 diabetes on a vegan diet or an American Diabetes Association diet for 22 weeks. Food was not provided. Long-term blood sugar (HbA1c) fell 0.96 points against 0.56, a gap too small to rule out chance. Weight fell 6.5 kg against 3.1 kg, a clear difference. When people who changed their medicine were left out, the blood sugar gap became clear. That is a fair way to look at it, but a secondary one.
Barnard 2022 is the only head-to-head of vegan against Mediterranean here. 62 adults tried each diet for 16 weeks, one after the other. Vegan won on weight, 6.0 kg lost against none, and on LDL. Mediterranean won on the top blood pressure number, by 5.9 mmHg. Insulin resistance was not clearly different. The study was run by a group that promotes plant-based eating, and it still published the blood pressure result against its own diet, which is worth noting.
Landry 2023, the Stanford twin study, has the strongest design here. 22 pairs of identical twins took part. One twin in each pair ate a healthy vegan diet and the other a healthy diet with meat, for eight weeks, with meals delivered for the first four. Against their own twin, the vegan twins had LDL 13.9 mg/dL lower and fasting insulin 2.9 microIU/mL lower, and weighed 1.9 kg less. Genes and upbringing are matched, which is rare and truly strong. Calories were not matched, so part of the LDL and insulin gap comes from the 1.9 kg.

What happened when people just ate it

People stick with it better than the stereotype suggests. In the Barnard diabetes study, all 99 people finished 22 weeks. At 74 weeks, 86 percent of the vegan group and 90 percent of the standard diet group were still in. 67 percent of the vegan group met the diet's own rules, against 44 percent of the standard group. But the 74-week results mostly showed no real difference on the main measures. Weight fell 4.4 against 3.0 kg, and long-term blood sugar 0.34 against 0.14 points, both too close to call. The gains in cholesterol and blood fats lasted in people whose medicine had not changed. That is the pattern across this research: strong early, then fading, with cholesterol the result that lasts.

Protein, and whether it muddies the result

Hitting a high protein target is harder here, but not impossible. Plant proteins usually have less leucine, a key building block for muscle, and the body absorbs them a bit less well. Getting 150 to 200 g a day takes planning around beans, soy and protein powders. It does not happen by accident. Data on muscle in these studies is thin. One of the main vegan studies reported 3.9 kg of fat lost out of 5.9 kg total and did not break down the rest, so no lean mass figure can be taken from it. Anyone pairing this diet with a weight loss drug or a training plan should solve protein first.

The measured intakes behind the protein figures are on the protein page.

What reliably moves

Measure	Direction	From
LDL (bad) cholesterol	Down, reliably	13.9 mg/dL lower than an identical twin at eight weeks. This is the strongest result for this diet, and the twin design makes it hard to explain away.
Body weight	Down	1.9 kg less than a twin in eight weeks, 5.9 kg against no diet change in sixteen weeks, and 6.5 kg against a standard diabetes diet in 22 weeks.
Fasting insulin and insulin resistance	Down	2.9 microIU/mL lower than a twin. The insulin resistance score fell by 1.0 to 1.3 across studies. The change tracked the drop in BMI and belly fat, so part of it is the weight loss.
Vitamin B12	Down without supplements, and nobody disputes this	52 percent of British vegan men were low in B12, in a group where not everyone took supplements. A Swiss group where most people took supplements had few people running low. B12 levels follow supplement use, so this is fully fixable, and it must actually be fixed.
Zinc and iodine	Down	Zinc was the most common shortfall in Swiss vegans, at 47 percent. Iodine was low in vegan groups in both Norway and Boston, without measured thyroid problems in the Boston group.
Omega-3 fats EPA and DHA	Down, and they do not recover	EPA and DHA levels are lower and do not improve with more time on the diet. That argues against the body adapting, and for either an algae-based supplement or accepting lower levels.

Long term, and serious health events

This is where the diet gets truly complicated, and where most summaries stop reading. Two large long-term studies disagree. The Adventist Health Study 2 followed 73,308 people. Vegetarians as a whole had a death risk score of 0.88, where under one means fewer deaths than meat eaters. For vegans alone it was 0.85, too uncertain to call. For vegetarians who ate fish it was 0.81, a clear result. A pooled look at two UK studies, 60,310 people including 2,228 vegans, was built on purpose around a health-minded meat-eating comparison group. It found no difference in deaths at all: vegetarians 1.02, fish eaters 0.96, low meat eaters 0.93. Neither settles it, and the most obvious difference between them is who they compared against. Two findings go against the diet and are usually left out. EPIC-Oxford found vegetarians had 22 percent less heart disease from narrowed arteries, and that shrank when the researchers accounted for cholesterol, blood pressure, diabetes and BMI. They also had 20 percent more strokes overall, driven by strokes from bleeding in the brain, and that did not shrink. The stroke finding is in the paper's published title. The fracture data is the starkest number for this diet. After adjustment, vegans had 2.31 times the hip fracture risk of meat eaters, equal to 14.9 more cases per 1,000 people over ten years. Adventist data suggests the extra risk is only in people not taking both calcium and vitamin D. That makes it a fixable problem, not an argument against the diet, and it has to be fixed rather than waved away.

Sources

Study in people2023
Cardiometabolic effects of omnivorous vs vegan diets in identical twins: a randomized clinical trial
JAMA Network Open
22 pairs of identical twins took part for eight weeks; in each pair one twin ate vegan and the other ate meat. The vegan twins had LDL (bad) cholesterol 13.9 lower, fasting insulin 2.9 lower, and lost 1.9 kg more. Calories were not matched between the groups. The lead author reported funding from Beyond Meat for work outside this study.
22 pairs of identical twins, one twin per pair randomised for eight weeks. Vegan against co-twin: LDL minus 13.9 mg/dL, fasting insulin minus 2.9 microIU/mL, weight minus 1.9 kg. Calories not matched. Lead author disclosed funding from Beyond Meat outside the submitted work.
Study in people2020
Effect of a low-fat vegan diet on body weight, insulin sensitivity, postprandial metabolism, and intramyocellular and hepatocellular lipid levels in overweight adults
JAMA Network Open
244 overweight adults went on a low fat vegan diet or made no change to their diet. The vegan group lost 5.9 kg, their insulin resistance score fell 1.3, and calories burned digesting food rose 14.1 percent. The study was run by a group that promotes plant diets, and it compared a diet against no diet at all.
244 overweight adults randomised to a low fat vegan diet or to make no dietary change. Weight minus 5.9 kg, HOMA-IR minus 1.3, thermic effect of food plus 14.1 percent. Conducted by an organisation that advocates plant-based diets; this compares a diet against no diet.
Study in people2006
A low-fat vegan diet improves glycemic control and cardiovascular risk factors in a randomized clinical trial in individuals with type 2 diabetes
Diabetes Care
99 adults with type 2 diabetes ate a low fat vegan diet or the American Diabetes Association diet for 22 weeks. Long-term blood sugar fell 0.96 points on vegan against 0.56, a gap too small to rule out chance across everyone. Weight loss was 6.5 kg against 3.1 kg, a clear win for vegan.
99 adults with type 2 diabetes, vegan against an ADA guideline diet, 22 weeks. HbA1c minus 0.96 against minus 0.56 percentage points, p = 0.089, not significant across all participants. Weight minus 6.5 against minus 3.1 kg, p < 0.001.
Study in people2009
A low-fat vegan diet and a conventional diabetes diet in the treatment of type 2 diabetes: a randomized, controlled, 74-wk clinical trial
American Journal of Clinical Nutrition
This followed the same diabetes study to 74 weeks, and the main results came out even. Weight loss was 4.4 kg on vegan against 3.0 kg, and long-term blood sugar fell 0.34 against 0.14 points, gaps too small to rule out chance. The cholesterol edge on vegan held up in people whose medicines had not changed.
The 74-week extension, and largely a null on the headline comparisons. Weight minus 4.4 against minus 3.0 kg (p = 0.25) and HbA1c minus 0.34 against minus 0.14 (p = 0.43). Lipid advantages persisted where medication had not changed.
Study in people2019
Risks of ischaemic heart disease and stroke in meat eaters, fish eaters, and vegetarians over 18 years of follow-up: results from the prospective EPIC-Oxford study
BMJ
This tracked 48,188 people for 18.1 years. Vegetarians had 22 percent less heart disease from blocked arteries, though much of that shrank once cholesterol, blood pressure, diabetes and weight were counted. Vegetarians had 20 percent more strokes, mostly bleeding strokes, and that did not shrink. It tracked what people ate, so it cannot prove cause.
48,188 participants, 18.1 years. Vegetarians 22 percent lower ischaemic heart disease (HR 0.78), attenuating to 0.90 on adjustment for cholesterol, blood pressure, diabetes and BMI. Vegetarians 20 percent higher total stroke (HR 1.20, 1.02 to 1.40), driven by haemorrhagic stroke, and that did not attenuate. Observational.
Study in people2013
Vegetarian dietary patterns and mortality in Adventist Health Study 2
JAMA Internal Medicine
This tracked 73,308 Seventh-day Adventists, and 2,570 died during the study. Vegetarians as a group had a somewhat lower death rate, and so did those who also ate fish. For vegans the drop was too small to rule out chance. Diet was asked about only once, at the start, and this kind of study cannot prove cause.
73,308 participants, 2,570 deaths. All vegetarians combined HR 0.88 (0.80 to 0.97). Vegans 0.85 (0.73 to 1.01), not significant. Pesco-vegetarians 0.81 (0.69 to 0.94). Observational, single baseline food frequency questionnaire.
Study in people2016
Mortality in vegetarians and comparable nonvegetarians in the United Kingdom
American Journal of Clinical Nutrition
This UK study followed 60,310 people, including 2,228 vegans, and 5,294 of them died. Vegetarians, fish eaters and low meat eaters died at about the same rate as regular meat eaters. There was no real difference in overall deaths.
The UK null that deserves equal prominence. 60,310 people including 2,228 vegans, 5,294 deaths. All-cause mortality against regular meat eaters: vegetarians HR 1.02 (0.94 to 1.10), fish eaters 0.96, low meat eaters 0.93. No significant difference in overall mortality.
Study in people2020
Vegetarian and vegan diets and risks of total and site-specific fractures: results from the prospective EPIC-Oxford study
BMC Medicine
This followed 54,898 people for 17.6 years on average. Even after weight and lifestyle were counted, vegans had a much higher risk of hip fracture than meat eaters, equal to 14.9 more cases per 1,000 people over ten years. Fish eaters and vegetarians also had somewhat more hip fractures. No group had more wrist or ankle fractures.
54,898 participants, mean 17.6 years. Hip fracture adjusted for lifestyle and BMI against meat eaters: fish eaters HR 1.26, vegetarians 1.25, vegans 2.31 (1.66 to 3.22), equal to 14.9 more cases per 1,000 over ten years. No differences for wrist or ankle in any group.
Study in people2009
Type of vegetarian diet, body weight, and prevalence of type 2 diabetes
Diabetes Care
This took one snapshot of 60,903 people, so it shows who had diabetes, not who got it later. Type 2 diabetes was found in 2.9 percent of vegans against 7.6 percent of people who ate meat. Vegans still had lower odds of diabetes after body weight was taken into account.
Cross-sectional prevalence, not incidence. 60,903 participants. Type 2 diabetes prevalence 2.9 percent in vegans against 7.6 percent in nonvegetarians, with adjusted odds ratio 0.51 for vegans even after adjusting for BMI.
Study in people2022
A Mediterranean diet and low-fat vegan diet to improve body weight and cardiometabolic risk factors: a randomized, cross-over trial
Journal of the American College of Nutrition
62 adults tried a Mediterranean diet and a low fat vegan diet, 16 weeks each. The vegan diet won on weight, 6.0 kg lost against none, and on LDL (bad) cholesterol. The Mediterranean diet lowered the top blood pressure number 5.9 points more. Insulin resistance did not clearly differ.
The only direct randomised comparison of these two patterns. 62 adults, crossover, 16 weeks per arm. Vegan won on weight (minus 6.0 kg against zero) and LDL; Mediterranean won on systolic blood pressure by 5.9 mmHg (p = 0.02); HOMA-IR not significant (p = 0.21).

What people report

These are things people say about their own eating. Nobody checked them, so they are not evidence. They are here because they tell you what to expect and what to watch for, which the studies do not. They cannot tell you whether anything works.

Better digestion and regularity, put down to fibre, reported very consistently.
More food on the plate for the same calories, described as the main reason it feels doable long term.
Early bloating and gas as fibre goes up, usually settling in two to four weeks.
Tiredness that clears up once B12, iron or total calories are sorted out. Often it did not clear up, because none of those was tested.
Trouble hitting protein targets while training, the most common complaint from people who also lift.
Strong social and ethical support, which shows up in the study data as unusually good sticking power.

Sources: r/vegan, r/PlantBasedDiet and r/veganfitness, plus how well people stuck to the diet in the studies, which is unusually good: 86 to 90 percent still in at 74 weeks in the Barnard diabetes study. Unchecked self-report, useful for what to expect and nothing else.

Who this is wrong for

Anyone who will not take B12. This is not a preference. It is the one nutrient missing from plant foods, and running low can cause nerve damage that does not heal.
Anyone who will not deal with calcium and vitamin D. Vegans had 2.31 times the hip fracture risk, and the Adventist data suggests that is limited to people not taking both.
Anyone who has had a stroke from bleeding in the brain, or is at high risk of one, until the EPIC-Oxford stroke finding is better understood. It did not shrink when disease risk factors were accounted for, and nobody knows why it happens.
Anyone with iron-deficiency anaemia that is not being checked, and children. In children, shorter height and lower iron stores have been seen, though the evidence for that is very weak.
Anyone trying to reach 1 gram of protein per pound of goal bodyweight without planning for it. It can be done, but it does not happen by default.

Questions

Does a vegan diet lower cholesterol?: Yes, and the evidence is unusually clean. In 22 pairs of identical twins, the vegan twin's LDL was 13.9 mg/dL lower than their twin's after eight weeks. Because the design matches genes and upbringing, that result is hard to explain any other way. Calories were not matched, though, so part of it comes from a 1.9 kg weight difference.
Do vegans live longer?: The two big long-term studies disagree, and that is the honest answer, not a dodge. A North American study of Seventh-day Adventists found vegetarians overall had a 12 percent lower death rate, and the vegan result alone was too uncertain to call. A pooled UK study, which compared against health-minded meat eaters, found no difference at all. Both only tracked people who chose their own diets, and neither settles it.
What about the stroke finding?: EPIC-Oxford found vegetarians had 20 percent more strokes overall over 18 years, driven by strokes from bleeding in the brain. That is about 3 more cases per 1,000 people over ten years. It is in the paper's published title, and summaries usually leave it out. Unlike the heart disease benefit in the same paper, it did not shrink when disease risk factors were accounted for. Nobody knows why, and a study that only watches people cannot tell us.
Is the hip fracture risk real?: It is the biggest warning sign for this diet. After adjustment, vegans had 2.31 times the hip fracture risk, equal to 14.9 more hip fractures per 1,000 people over ten years. Adventist data suggests the extra risk is only in people not taking both calcium and vitamin D, which makes it fixable. Fixing it means actually taking supplements and getting tested, not assuming your food covers it.
Can I build muscle on it?: Yes, but you have to plan the protein rather than expect it. Plant proteins have less leucine and the body absorbs them a bit less well, so a high target needs beans, soy and protein powder on purpose. The muscle data inside these studies is too thin to quote, which is worth knowing in itself.