Can fasting make chemotherapy more effective?

You’ve probably heard about the benefits of fasting a couple of times a week to help prevent a variety of diseases, including cancer.

Mounting evidence suggests fasting can also help to beat cancer alongside conventional treatment.

Recent research by the Ackerman Cancer Center in the US, found that a form of fasting can sensitise breast cancer cells to chemotherapy both at the clinical and pathological levels.

The Fasting Mimicking Diet

The Fasting Mimicking Diet, or FMD, is a meal programme where participants consume a very low-calorie diet for five days, usually once a month.

The researchers found that fasting deprives proliferating cancer cells of nutrients, growth and other factors, which renders them more sensitive to cancer therapy and increases cell death.

Evidence suggests it will work well to help prevent breast cancer reoccurring too, as metabolic disturbances, like too much insulin and blood sugar, increase the risk of breast cancer recurring. By reducing fat and insulin levels, intermittent fasting could help reduce that risk.

This builds on other research done in the field. A study done by scientists at the University of Southern California looked at the impact fasting had on breast, urinary tract and ovarian cancers in mice.

Cycles of fasting combined with chemotherapy cured 20 per cent of mice with a highly aggressive form of cancer, while 40 per cent with a limited spread of the same cancer were cured. None survived if they were treated with chemotherapy alone.

The cancer cell effectively commits suicide. We know cancer cells need plenty of glucose. Without blood supplies of glucose (often from high fructose corn syrup in junk food), cancer cells wither away. Healthy cells, on the other hand, switch to burning fats (this is when your body goes into ketosis). Human trials are planned. However, given the gruelling nature of chemotherapy, patients may find going without eating for long periods difficult.

Can Keto help?

The  Ketogenic Diet – a way of eating designed to produce the ketosis so loathed by the cancer cells – may work in a similar way. In the Ketogenic diet, carbohydrates are off the menu, other than non-starchy vegetables – fizzy, soft drinks and dairy are banned. A limited amount of quality, fresh protein (fish, chicken) is allowed. Healthy fats - like virgin olive oil, fish oils, flaxseed, macademia and other nuts and seeds, coconut oil are encouraged.

When Dr. Dominic D'Agostino of the University of South Florida removed carbohydrates from the diets of lab mice, the mice survived highly aggressive metastatic cancer even better than when they were treated with chemotherapy. Anecdotal reports suggest this has the potential for similarly positive results in humans.

'Your normal cells have the metabolic flexibility to adapt from using glucose to using ketone bodies. But cancer cells lack this metabolic flexibility. So, we can exploit that,' says Dr. D'Agostino.

There is still much research to do, and there are question marks over whether fasting or ketogenic diets are right for everyone. Many scientists believe that one-size-fits-all approach is simply not appropriate, and the day will come where we can take genetic tests to find the diet that work best for us as individuals.

If you are considering a fasting or a ketogenic diet, do discuss with your doctor or dietician first.

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The basic unit of all living organisms. Full medical glossary
The use of chemical substances to treat disease, particularly cancer. Full medical glossary
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