The incidence of cancer is 10 to 15 % less in vegetarians and vegans compared to meat consumers. Small consumers of meat, and those who eat fish, also have a lower risk.
Cancer is one of the main causes of death in the world. Colorectal, breast and prostate cancers represent almost 40 % of all new cancer diagnoses in Europe together, and it is estimated that almost 40 % of cancer cases could be avoided thanks to changes affecting the lifestyle and the environment.
The protective potential of vegetarian diets
Vegetarian diets, which exclude the consumption of foods of animal origin, could be associated with a lower risk of cancer. In addition to excluding red meat and transformed meat, which are associated with an increased risk of colorectal cancer, vegetarians and vegans also generally consume more plants than meat consumers, which could also help reduce the risk of certain localized cancers.
To learn all about vegetarian and vegan diets: The best way to eat vegetableby Fabien Badariotti and Léa Lebrun
What great scientific studies reveal
Two major prospective studies, the Epic-Oxford study and the Health Study of Adventists-2 (AHS-2), have suggested that vegetarians may have a lower risk of developing cancer compared to meat eaters.
Adventist Health Study-2
In 2025, an analysis of the Adventist Health Study-2, relating to 79,468 participants, showed that vegetarian people have a reduced risk of cancerin particular for colorectal (-21 %), stomach (-45 %) and lymphoproliferative (-25 %) cancers, but also breast and prostate. Were considered vegetarians Vegans, lacto-ovo-vegetarians and pesco-vegetarians. The Adventist Health Study study is a cohort of 95,863 Adventists on the North American seventh day formed between 2002 and 2007.
The results of a major British study
A vast study by researchers from the University of Oxford used information identified by the British Biobank, a repository which includes epidemiological data and the health files of half a million volunteers.
On the half-million individuals present in the Biobank, the data of 472,377 adults aged 40 to 70 were used. Among them, 247,571 (52 %) ate meat more than five times a week, 205,382 (44 %) ate meat five times a week or less, 10,696 (2.2 %) ate fish but no meat and 8,685 (1.8 %) were vegetarian and/or vegan.
Fewer cancers in fish eaters and vegetarians
During the 11 years of follow -up, 54,961 (12 %) developed a type of cancer. In total, the risk of developing a tumor for those who ate meat at most five times a week was 2 % lower than that of those who ate meat at least five times a week. The risk of those who ate fish, but no meat, was 10 % lower. And the risk was 14 % lower in vegetarians and vegans.
Read also: 5 Good habits to reduce the risk of colorectal cancer
Among cancers, the Prostate cancer risk was 20 % lower in men who ate fish but no meat, and 31 % lower in vegetarians and vegans. A 18 % reduction in risk of breast cancer Was observed in vegetarian women compared to those who ate meat more than five times a week, but the difference was linked to a lower body mass index in vegetarian, obesity and overweight being a risk factor for this disease.
What to remember
In conclusion, this vast British study shows that low to moderate to moderate meat, fish or monitoring a vegetarian or vegan diet are associated with a lower risk of cancer, which can be the result of food factors and/or differences in lifestyle, such as smoking. Small meat eaters had a lower risk of colorectal cancer, vegetarian women a lower risk of breast cancer after menopause and vegetarian men or fish eaters a lower risk of prostate cancer.
However, the authors warn in their conclusions that the nature of their work does not make it possible to establish a cause and effect relationship between food and risk of cancer. In addition, the reduction in the risk linked to the follow -up of a vegetarian or vegan diet, a diet low in meat, or regular consumption of fish, if it is proven, is low.
