The fasting-mimicking diet – a short-term, low-protein, low-carbohydrate diet – improves metabolism and increases immune cell populations that target cancer, according to a 2021 study. Participants who followed the five-day dietary protocol found it easy to adhere to and experienced few ill effects other than fatigue.

The study involved 101 cancer patients who followed a fasting-mimicking diet that provided up to 600 calories on the first day and up to 300 calories on the remaining days. They repeated the dietary protocol every three to four weeks – up to eight times in all. The patients followed their normal diets between the fasting-mimicking periods but were encouraged to adhere to healthy lifestyles.

The study’s investigators found that the fasting-mimicking diet reduced the patients' glucose by 18 percent, insulin by 50 percent, and IGF-1 (a growth factor involved in cancer development) by 30 percent. These changes remained stable over the duration of the study. They also found that levels of immunosuppressive cells decreased, but CD8+ T cells – the primary drivers of anti-tumor immunity – increased.

Research shows that the fasting-mimicking diet creates a hostile microenvironment for cancer cells, sensitizing them to chemotherapy drugs and promoting cell death while preserving healthy cells. This sensitization exploits cancer cells' inability to adapt to extreme environments – a critical aspect of treating certain types of aggressive cancers and preventing their recurrence.

These findings suggest that the fasting-mimicking diet is a safe and useful adjunct to chemotherapy. Learn about other benefits of the fasting-mimicking diet in this video featuring its creator, Dr. Valter Longo.

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