A vegan diet means eating only plants like fruits, vegetables, grains, and beans, and avoiding all animal products such as meat, dairy, and eggs. The claim says that switching to this kind of diet makes you healthier and helps you live longer.
See the scientific wording
Adopting a vegan dietary pattern leads to improved health outcomes and increased life expectancy.
There's disagreement
ObservationalThe 3 studies we reviewed point in different directions — there's no clear consensus.
What the research says
3 studies reviewedSupporting (2)
Nutritional associations with decelerated epigenetic aging: vegan diet in a Dutch population
Cross-Sectional StudyHuman2025
The study found that vegans showed signs of aging more slowly in their blood tests compared to meat eaters, but only a few vegans were studied, so we need more research.
Systematic Review With Meta-AnalysisMeta-analysis2025
The study looked at whether eating vegan reduces inflammation, and it found a small trend that wasn't strong enough to be sure, so we can't say for sure that being vegan makes you live longer.
Contradicting (1)
Cohort StudyHuman2020
Vegans had more broken bones, which is not healthy, so this study does not support the idea that a vegan diet makes you healthier.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 2 supporting, 1 contradicting studies
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