Ketogenic Diet

Awareness of the role of sugar metabolism in various cancers has increased interest in low carbohydrate diets. Popular low carbohydrate diets include the ketogenic, Atkins, paleo, primal, Bulletproof, and Zone diets. What these have in common is an emphasis on decreasing carbohydrate intake in favor of increased fat and protein intake.

The ketogenic diet in particular has been studied for its anti-cancer benefits, because in animal studies, it has been shown to increase survival with some types of brain tumor. This has not been well-replicated in humans, but there are several published case reports that demonstrate improvement, especially in brain tumors and breast tumors. More studies are underway.  The ketogenic diet relies on fat as the main source of calories, with some protein and extremely low amounts of carbohydrates. When a ketogenic diet is used as a means to control cancer, it must also be a calorically restricted diet in order to force the body to retain ketones

While the ketogenic diet is generally considered safe, particularly when it is done under the supervision of a registered dietitian or other knowledgeable healthcare provider, there are concerns about the ketogenic diet, and it is therefore not routinely recommended for cancer patients. The ketogenic diet tends to be higher in animal proteins and fats, and increased animal fats, including excessive red meat, have been associated with an increased risk of breast and colon cancers.

Additionally, the ketogenic diet can be very low in fiber. Fiber is essential for gut health, and research is continually emerging about the importance of gut health, the microbiome, and the associations of poor gut health with chronic disease, including cancer. The ketogenic diet also does not supply sufficient B vitamins or vitamin D, so these need to be supplemented.  Finally, this is a hard diet for many individuals to follow, limiting its potential value.

If you feel strongly about trying the ketogenic diet, or if it is recommended by your trusted medical provider, please see a qualified registered dietician (RD) for guidance. Many cancer centers have nutrition experts on their staff to help patients navigate the sometimes complicated world of specialized nutrition.