Cancer Patients Lose More Weight on Ketogenic Diet

Cancer patients who followed a ketogenic diet were more successful in losing body fat and lowering their insulin levels compared to similar patients who followed an American Cancer Society-recommended low-fat diet. Those are the results of a study published by the University of Alabama at Birmingham.

Researchers chose 45 overweight or obese women suffering from ovarian or endometrial cancer for the study. Those patients were not actively attempting to lose weight and were not on a special diet at the time of the trial. Each was assigned to either a ketogenic diet or a diet recommended by the American Cancer Society.

Women with ovarian and endometrial cancers were chosen because of the associated risks factors and health outcomes with those two types of cancers.

"Ovarian and endometrial cancers are some of the deadliest cancers among women in the United States," said study co-author Kevin Fontaine, Ph.D. "These cancers are also strongly linked to obesity and higher levels of insulin."

A ketogenic diet was chosen for the study because it is designed to limit the carbohydrate intake as those foods increase and glucose and insulin.

"Because cancer cells prefer to use glucose, diets that limit glucose may be beneficial," said co-author Barbara Gower, Ph.D. "These diets are called 'ketogenic' because they allow the body to burn fat as a fuel. Some of the fat is converted to ketones, which are used by the brain and many other tissues as another type of fuel. Because they limit glucose and several growth factors, ketogenic diets will limit the ability of cancer to grow, which gives the patient's immune system time to respond."

"Compared to the diet recommended by the American Cancer Society, which is moderate-to-high-carbohydrate, high-fiber and low-fat, 12 weeks on a ketogenic diet, which is low-carbohydrate, high-fat, produced significantly lower levels of fat mass," Fontaine said. "The ketogenic diet group also had significantly lower levels of fasting insulin."

Previous studies of the ketogenic diet involving animal and humans were shown to be beneficial with other types of cancers. This study showed favorable effects with ovarian and endometrial cancers.

"First, it lowered insulin, which is a growth factor," Gower said. "High-glucose diets result in high insulin, which stimulates cancer cell growth. Second, this ketogenic diet resulted in selected loss of visceral fat. Visceral fat is the 'bad fat' in the abdomen that is associated with elevated risk for cancer and diabetes. Third, we noted that patients with higher ketones had lower levels of IGF-1. IGF-1 is also a growth factor that stimulates cancer cells."

The study authors hope to expand their research to see how a ketogenic diet may impact cancer treatment.

Click here to read more in the Journal of Nutrition.