High Carb Diet Linked to Prostate Tumor Growth

Having too much insulin in the blood, a condition called hyperinsulinemia, is associated with poorer outcomes in patients with prostate cancer. Vasundara Venkateswaran, Ph.D., of Sunnybrook Health Sciences Centre in Toronto and colleagues investigated whether high insulin levels caused by eating a diet high in refined carbohydrates would lead to more rapid growth of prostate tumors in mice.

Forty mice were randomly assigned to either a high carbohydrate-high fat diet or a low carbohydrate-high fat one for nine weeks. The researchers measured the animals' weight, tumor size, and insulin levels weekly. Mice on the high carbohydrate diet gained more weight, had faster growing tumors, and had higher insulin levels than mice on the low carbohydrate diet.

"Our results provide support for the concept that diets associated with a reduction in insulin level may have benefits for prostate cancer patients, particularly for the subset of patients who are hyperinsulinemic," the authors write.