A new study of the health of vegetarians shows that they are less likely to develop cancer.

Vegetarians have  lower cancer risk

A vegetarian diet seems intrinsically healthy, maybe because a vegetarian tends to eat a lot of fresh fruits and vegetables and accompanying fiber.  But few large, or long-term, studies have been carried out on the health impact of the vegetarian diet.  In a new report, researchers at the Cancer Research UK Epidemiology Unit at Oxford University gather data from the original Oxford Vegetarian Study and a more recent one called EPIC-Oxford.

The research involved more than 61,000 people divided up into pure vegetarians and vegans (20,601 people), fish-eating vegetarians (8,562 people) and meat-eaters (32,403 people) followed for around 12 years. Overall, vegetarians are 12% less likely to get cancer than meat-eaters. The incidences of 20 different cancers was recorded and some interesting differences between vegetarians and meat-eaters noted.

Cancer of the stomach, bladder and ovary were less common among vegetarians than among meat-eaters.  Also cancers of the blood, including leukemia, non-Hodgkin's lymphoma and multiple myeloma were, taken together, 45% less common among vegetarians. There was also a decreased risk of prostate cancer among fish-eating vegetarians compared to the meat-eaters. 

How do these findings on the vegetarian diet compare to those of other studies? The Adventist Health Study in California showed that vegetarians have a lower risk of colon and prostate cancer than non-vegetarians.  And the UK Women's Cohort Study showed a lower risk of breast cancer in vegetarians.  As with all these studies, there are challenges in assessing people's diet - are they really vegetarian and which vegetarian foods are the most healthy? The researchers declare themselves most surprised by the link between the vegetarian diet and a lowered risk of blood cancers.  This deserves a fuller investigation.  There is clearly much more to be learned about how the vegetarian diet affects both overall cancer risk and the risk of individual types of cancer.