VEGETARIAN diets are associated with a lower risk of cancers in the pancreas, breast, prostate, kidney, and multiple myeloma, the largest study to date on this topic has found.
Although, vegetarianism was also associated with a higher risk of squamous cell carcinoma of the oesophagus in the 2026 pooled analysis.
The Cancer Risk in Vegetarians Consortium
Researchers established the Cancer Risk in Vegetarians Consortium, bringing together data from nine prospective studies across three continents and analysing more than 1.8 million people with diverse diets. Most of those studied lived in the UK or USA.
Cancers investigated included those of the gastrointestinal tract, lung, reproductive system, urinary tract, and blood. Skin and cervical cancer were omitted from analysis due to a lack of data regarding their major non-dietary causal factors: exposure to UV radiation and human papillomavirus, respectively.
Participants were split into five groups: meat eaters, poultry eaters, pescatarians, vegetarians, and vegans. Resurvey was carried out at a median of four to 14 years after baseline. Cancer cases were identified through linkage to cancer registries and defined using WHO’s International Classification of Diseases.
Of the entire cohort, 90.5% were meat eaters, 3.1% were poultry eaters, 2.4% were pescatarians, 3.5% were vegetarians, and 0.5% were vegans.
Vegetarianism and Cancer Risk
Vegetarians had lower risks for cancers of the pancreas, breast, prostate, kidney, and multiple myeloma, but higher risk of squamous cell carcinoma of the oesophagus than meat eaters.
Upon sensitivity analysis, the most consistent findings were that vegetarians had a lower risk of kidney cancer and higher risk of squamous cell carcinoma of the oesophagus.
Poultry eaters exhibited a lower risk of prostate cancer and pescatarians had a lower risk of colorectal, breast, and kidney cancer than meat eaters.
Potential Underlying Mechanisms
Previous studies suggest that vegetarians typically have several favourable diet-related characteristics, including relatively low saturated fat intake and higher intakes of dietary fibre. They have also shown low BMI and cholesterol compared with meat eaters.
Alongside these favourable characteristics, vegetarians and vegans generally had lower intakes of several nutrients, including protein, vitamin B12, and vitamin D.
Researchers suggested that this might explain the higher risk for squamous cell carcinoma of the oesophagus in vegetarians.
They also warned that the generalisability of findings should be approached with caution, as dietary and nutritional intakes of both vegetarians and non-vegetarians can vary across and within populations.
References
Dunneram Y et al. Vegetarian diets and cancer risk: pooled analysis of 1.8 million women and men in nine prospective studies on three continents. Br J Cancer. 2026;DOI:10.1038/s41416-025-03327-4.
Dunneram Y et al. Methods and participant characteristics in the Cancer Risk in Vegetarians Consortium: a cross-sectional analysis across 11 prospective studies. BMC Public Health. 2024;24:2095.
Key TJ et al. Plant-based diets and long-term health: findings from the EPIC-Oxford study. Proc Nutr Soc. 2022;81:190-8.
Featured image: I-Wei Huang on Adobe Stock
