Cancer: A 'fasting mimicking' diet may aid chemotherapy

A 'fasting mimicking' diet may enhance the effects of initial rounds of chemotherapy in patients with breast cancer, according to a randomized, controlled phase 2 clinical trial published in Nature Communications. Fasting mimicking diets are low-calorie, low-protein diets developed to elicit similar metabolic responses to those caused by water-only fasting.

Preclinical evidence suggests that short-term fasting and fasting mimicking diets can protect healthy cells against chemotherapy, while simultaneously rendering cancer cells more vulnerable to the treatment. However, clinical research evaluating the potential of short-term fasting in patients with cancer is in its infancy.

In a trial conducted by Judith Kroep and colleagues, 129 patients with HER2-negative stage II/III breast cancer followed either a fasting mimicking diet or their regular diet for 3 days prior to and during neoadjuvant chemotherapy (treatment given as a first step to shrink a tumour before surgery). The fasting mimicking diet was a plant-based, low amino-acid substitution diet, consisting of soups, broths, liquids and tea. Although no difference in toxicity was observed between the treatment and control groups, the effects of neoadjuvant chemotherapy on tumour response were reinforced in patients in the fasting mimicking diet group. Follow up on (relapse free) survival is ongoing.

The results of this study suggest that cycles of a fasting mimicking diet are safe and effective as a supplement to chemotherapy in women with early breast cancer. These findings, together with preclinical data, encourage further exploration of the benefits of fasting combined with cancer therapy.