Largest ever study of vegetarian diets and cancer shows lower risk of 5 cancers

A woman with tattoos smiles whilst eating a salad in a bright kitchen. She wears a black vest, jeans, and a headband, standing near the cooker and sink with plants and dried flowers in the background.

A major new study funded by World Cancer Research Fund has revealed how appropriately planned vegetarian diets may help reduce the risk of specific cancer types

Author: World Cancer Research Fund

Published: 27 February 2026

This could help many people stay health, as there are 3 million vegetarians in the UK and interest is growing in many parts of the world.

The research, led by scientists at Oxford Population Health’s Cancer Epidemiology Unit, pooled data from more than 1.8 million people across three continents through the Cancer Risk in Vegetarians Consortium – the largest ever study of largest ever study of non-meat diets and cancer risk.

They compared the risk of 17 different cancers across five diet groups: meat eaters, poultry eaters (do not eat red or processed meat), pescatarians (fish eaters), vegetarians (eat dairy and/or eggs), and vegans.

Compared with meat eaters, vegetarians had:

21% lower risk of pancreatic cancer
9% lower risk of breast cancer
12% lower risk of prostate cancer
28% lower risk of kidney cancer
31% lower risk of multiple myeloma.

However, vegetarians had:

Nearly double the risk of squamous cell carcinoma of the oesophagus.

More information on all cancer types

Tim Key

Emeritus Professor of Epidemiology at Oxford Population Health, and co-investigator

Dietary patterns that prioritise fruit, vegetables, and fibre-containing foods, and avoid processed meat, are recommended to reduce cancer risk. Our study helps to shed light on the benefits and risks associated with vegetarian diets.

Aurora Perez Cornago,

Principal investigator of the study and formerly Associate Professor at Oxford Population Health

The higher risk of oesophageal squamous cell carcinoma in vegetarians and bowel cancer in vegans may relate to lower intakes of certain nutrients more abundant in animal foods. Additional research is needed to understand what is driving the differences in cancer risk found in our study

Dr Helen Croker

Assistant Director of Research and Policy at World Cancer Research Fund International

The results suggest non-meat diets are linked to lower risks for some cancers, though not all, highlighting important differences between cancer types and the role of different dietary patterns. To increase your overall protection from cancer, our advice is to build meals around wholegrains, pulses, fruit and vegetables, and avoid processed meat and limit red meat.

Yashvee Dunneram

First author of the study, and former postdoctoral epidemiologist at Oxford Population Health

Among the 72,000 vegetarians and vegans included in our study, the numbers of cases for some cancers were small, which limits the certainty of some findings. Moreover, nutrient intakes and overall diet quality vary substantially within and between vegetarian populations. Our next challenge is to collect more data on vegan diets and more data from other parts of the world.

There were no statistically-significant differences in risk for colorectal, stomach, liver, lung (in never smokers), endometrial, ovarian, mouth and pharynx, or bladder cancers, or non-Hodgkin lymphoma, leukaemia, and oesophageal adenocarcinoma in vegetarians.

Vegans had a statistically significant higher risk of colorectal (bowel) cancer when compared with meat eaters. For the other cancers studied, there was no evidence that risk in vegans differed from meat eaters, and for some less common cancers there were too few vegan cases to analyse. Further studies are needed to confirm these results in the vegan population.

Pescatarians had lower risks of breast and kidney cancers, as well as a lower risk of bowel cancer. Poultry eaters were found to have a lower risk of prostate cancer.

The full findings were published on 27 February 2026 in the British Journal of Cancer.

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