Does a Keto Diet Work for Prostate Cancer?
All cells of the human body require energy in the form of Adenosine TriPhosphate (ATP) to support life. If you remember way back in high school, you learned that the mitochondria are the “powerhouse” of the cell as it produces the majority of ATP. When the mitochondria are impaired, their malfunction is implicated in the majority of today’s most concerning chronic and degenerative diseases including obesity, cardiovascular disease, cancer, and diabetes, to name a few.
What are the ketogenic, mitochondria, and health connections?
Initially, ketogenic diets were used to treat seizures, but recent research indicates that benefits related to the management of epilepsy, weight loss, metabolic syndrome, and type 2 diabetes can be achieved with an approach that is less restrictive in carbohydrate and protein, and therefore more satisfying, sustainable, and feasible for the general population.
What is a Ketogenic Diet?
Ketogenic diets (KDs) are diets that mimic the metabolic state of fasting by inducing a physiological rise in the two main circulating ketones, acetoacetate and beta-hydroxybutyrate (BHB).
This is a simple version of how the ketogenic diet works.
When your cells are deprived of glucose (sugar) as their primary source of energy, your body kicks in the next gear and utilizes fat for fuel in the form of ketones.
One can create ketones from either fasting for a prolonged period, anywhere from 16 hours a day or for several days, or from eating a high-fat diet, which is what a ketogenic diet is.
To be clear, a ketogenic diet (KD) is not a high protein diet like a Paleo form of eating. It is a fat diet where lard is in, along with other oils, coconut being a favorite, butter, avocados, etc. Although, it isn’t uncommon for people to use a keto supplement alongside their diet.
The Ketogenic Diet and Cancer Connection
KDs target the Warburg effect, a biochemical phenomenon in which cancer cells predominantly utilize glycolysis (burns sugar) instead of oxidative phosphorylation (OXPHOS) to produce ATP (energy). Don’t get caught up on what OXPHOS means or how it works for now but know that healthy cells work by using this metabolic pathway.
Thus, the rationale in providing a fat-rich, low-carbohydrate diet in cancer therapy is to reduce circulating glucose levels and induce ketosis such that cancer cells are starved of energy while normal cells adapt their metabolism to use ketone bodies and survive.
To date, the most reliable evidence for KD in suppressing tumors has been reported for glioblastoma (a type of brain cancer).
The proposed mechanism for how the Ketogenic diet works for cancer is like this.
Cancer cells have dysfunctional mitochondria and lack specific enzymes necessary for effective ketone body utilization. In other words, malignant cells can’t use ketones for energy but healthy cells can.
Free fatty acids and ketone bodies are considered to become a significant fuel for normal tissues of cancer patients as a consequence of developing insulin resistance. Additionally, ketone bodies have been shown to suppress protein catabolism during starvation (more on this further down.)
Ketogenic Diet and Prostate Cancer: Yes or No?
There have been no studies on KD and prostate cancer.
However, there is a small pilot, non-randomized study going as we speak looking and this dietary approach among a sample of 12 overweight or obese prostate cancer patients on active surveillance. The result will not be available until the Spring of 2021.
Besides there being no studies, should a man with prostate cancer implement a KD?
Yes and no.
Here’s the deal;
One mice study looking at the effects of a no carbs keto diet (NCKD), 10% carb diet, and a 20% carb diet on prostate cancer showed is no difference between low-carbohydrate and no-carbohydrate diets regarding prostate cancer growth and progression.
The other important point is that most types of prostate cancer are not glycolytic cancers like glioblastoma’s thus the Warburg effect does not apply. Clinically this is relevant, as this prostate cancer will not appear on fluorodeoxyglucose (FGD) PET scans. However, in the late stage, more aggressive metastatic prostate cancer there may be more of a Warburg effect and have a high glucose uptake.
In other words, low-grade prostate cancer and high-grade metastatic prostate are two entirely different animals in how they behave.
Dr. Geo’s Take On the Ketogenic Diet and Prostate Cancer
A low carbohydrate diet of about 50 to 60g of carbs total (not sugar, carbohydrates) a day is still, eliminating refined; processed carbs is still essential for early-stage prostate cancer without metastasis or positive FDG PET scan.
The reason why a low-carb diet is vital to beat non-metastatic prostate cancer is not due to the glucose uptake of cancer cells, but the problems of excess insulin production resulting in insulin resistance that promotes the disease. In fact, there is research to suggest that patients with early-onset, type one diabetes mellitus (not type two diabetes) whose pancreas is no longer able to produce insulin are significantly less likely to develop prostate cancer, independent of diet changes.
If a huge guy is diagnosed with prostate cancer, then his high basal metabolic index (BMI) increases the risk of not only getting prostate cancer but dying from it.
It is a good idea for an overweight person with prostate cancer to restrict carbs as low carb diets, and a KD has shown to help with weight loss.
Lastly, ketones from fasting would be contraindicated in cancer patients with rapid weight loss (cachexia) unless a higher fat intake is consumed to avoid further weight loss. Additionally, ketone bodies have been shown to suppress protein catabolism during starvation – meaning that one can maintain muscle from breaking down while utilizing ketones for energy.
Adding medium-chain triglyceride (MCT) to KD in a study to five severely cachectic cancer patients for one week induced a significant weight gain of 2 kg and improved their performance status.
The bottom line is this: A low-carbohydrate, non-ketogenic diet is recommended for prostate cancer with few exceptions: one if the patient has a high BMI, or if prostate cancer is more advanced and shows on glucose dependant PET scan.
My Favorite Books on the Warburg Effect, Metabolic Approach, Ketogenic approach on Cancer