Specific dietary factors known to promote the growth of cancer cells have been known for many years. Studies show that the rate of cancer in a population is directly proportional to the percent of animal fat consumed in the diet of that population. Evidence supporting this can be seen in Asian countries like Japan, where rates of breast cancer are very low, compared to Western countries where the rates are consequently higher. However, breast cancer rates increase significantly when Japanese women consume the rich Western diet or migrate to Western countries and forego their native low-fat diet.
The fat content of the traditional Japanese diet is less than 10%, compared to the typical Western diet where animal products are the center of each meal, resulting in 37-40% of its calories from fat.
Studies have also shown that a diet rich in fruits and vegetables can improve the chances of survival in those patients that already have cancer. The higher the percentage of fat in the diet, the lower the survival rate. Higher body weight is also associated with higher rates of dying from breast cancer. Thinner women have less lymph node involvement, while heavier women have more lymph node involvement, increased rates of recurrence, and less chance of survival.
An overwhelming amount of evidence concludes that a diet devoid of animal products and rich in whole, plant foods not only helps to prevent cancer from becoming a threat to one's health but can also increase the chances of survival in those already diagnosed with cancer.
(1) "Breast Cancer: Survival and Prevention" by PCRM
(2) Purchase PCRM's "Cancer Survivor's Guide - Foods that Help You Fight Back!"
(3) Using Diet to Prevent and Treat Breast Cancer