Metabolic Health, Diet & Exercise
Research increasingly links metabolic health with cancer risk and outcomes. Obesity, insulin resistance, high blood sugar, and related metabolic problems have been associated with worse outcomes in several cancers and with a greater risk of aggressive or fatal prostate cancer.
Doctors and researchers such as Robert Lustig and Jason Fung emphasize how diet, obesity, insulin resistance, and metabolic dysfunction may contribute to an environment favorable to cancer growth. Both advocate reducing added sugar and refined carbohydrates and eating primarily whole, minimally processed foods. Fung also emphasizes fasting as a way to lower insulin and improve metabolic health.
This does not mean that sugar causes prostate cancer or that eliminating carbohydrates can cure it. But maintaining a healthy weight, good insulin sensitivity, muscle mass, and overall metabolic health may be particularly worthwhile for men with prostate cancer—especially those receiving hormone therapy, which can worsen metabolic health.
What Should You Eat?
There is no single diet proven to treat prostate cancer. A dietary pattern that supports good metabolic health is a reasonable goal.
Useful principles include:
Eat primarily whole, minimally processed foods
Minimize added sugar, refined carbohydrates, and ultra-processed foods
Include adequate protein to help maintain muscle
Eat vegetables and other fiber-rich foods
Avoid gaining excess body fat and, when appropriate, work toward a healthy weight
For people who are insulin resistant, reducing carbohydrates may help improve blood sugar, insulin levels, weight, and other metabolic markers.
A therapeutic ketogenic diet is a different question. It is being studied as a possible metabolic cancer therapy but has not been established as a treatment for prostate cancer.
Fasting and Cancer
Jason Fung has written extensively about fasting as a way to lower insulin, improve insulin sensitivity, and reduce excess body fat.
Fasting also affects processes such as autophagy, which has led researchers to investigate whether fasting or fasting-mimicking diets might influence cancer or responses to treatment.
The evidence for fasting as a cancer treatment in humans remains limited. For someone with prostate cancer, fasting is best considered primarily as a metabolic-health strategy, and more intensive fasting during treatment should be discussed with the medical team.
Exercise and Muscle Matter
Exercise improves insulin sensitivity, cardiovascular fitness, strength, and overall metabolic health.
It is particularly important for men receiving androgen-deprivation therapy (ADT), which can cause loss of muscle and bone, increased body fat, fatigue, and worsening metabolic health.
Resistance training helps preserve muscle and strength, while aerobic exercise supports cardiovascular fitness. Combining the two is particularly useful.
Exercise is an important way to maintain strength, independence, metabolic health, and quality of life during and after prostate cancer treatment.
Learn More
Dr. Fung's book examining cancer through genetics, evolution, metabolism, and the body's internal environment.
Videos
A discussion of sugar, insulin resistance, metabolic health, and chronic disease.
Dr. Fung discusses cancer, obesity, insulin resistance, diet, and other metabolic factors that may influence cancer development and growth.
A discussion of exercise and its role in prostate cancer care.