NEW YORK (Reuters Health) - A new study provides more evidence that animal-derived foods increase the risk of endometrial cancer, while foods from plant sources reduce it.
Women who received the most calories from animal protein had twice the risk of the disease compared to those who took in the fewest calories from animal sources, Dr. Wang-Hong Xu of Fu Dan University School of Public Health in Shanghai and colleagues found.
High levels of calories from animal fat boosted the risk by 50 percent. However, the women who ate the most protein from plant sources cut their endometrial cancer risk by 30 percent.
The results suggest that it's the source of fat or protein, not the macronutrients themselves, that is related to endometrial cancer risk, Xu and his team conclude.
There is already strong evidence that eating plenty of fruits and vegetables reduce endometrial cancer risk, while animal foods increase it, the researchers note in the International Journal of Cancer. But studies on the association between various vitamins and minerals, and the disease have had mixed results.
To better understand the relationship, the researchers compared 1,204 women recently diagnosed with the disease and 1,212 healthy women who severed as a comparison group (controls). Chinese women generally eat fewer processed and enriched foods than Western women, Xu and his team note, and rarely take supplements.
The researchers analyzed the patients' diet and determined how many calories from a particular source a woman consumed for every 1,000 calories she ate.
Women who consumed the most calories had the greatest risk of endometrial cancer, the researchers found. Saturated and monounsaturated fats increased the risk, but there was no association between polyunsaturated fats and cancer risk.
The researchers also found that vitamin A, beta-carotene, vitamin C, vitamin E and fiber from food, as well as vitamin supplements, were associated with a lower risk of the disease.
These findings suggest that the relationship between endometrial cancer risk and macronutrients may depend on their sources, with nutrients of animal origin associated with higher risk and nutrients of plant origin linked to a lower risk, they conclude.
SOURCE: International Journal of Cancer, April 15, 2007.