A few days of fasting may delay tumor progression and improve chemotherapy, a new study in mice reports. The findings indicate that fasting prior to chemotherapy treatment protects animals – and possibly humans – against the side effects of treatment. Here, Valter Longo and colleagues show in mice that fasting for 2 days in the absence of other treatments can delay the progression of different types of cancer, and may in some cases be just as effective as toxic chemotherapy drugs. However, the combination of fasting and chemotherapy appears to be more effective at making normal cells stronger (more able to resist damage from chemotherapeutic drugs) than either alone. In fact, combined fasting and chemotherapy promoted long-term, cancer-free survival in up to 40 percent of mice with neuroblastomas. Although clinical trials testing the effect of fasting in cancer treatment are still in early stages, these studies suggest that fasting cycles have the potential to boost the efficacy of chemotherapy. The results are particularly relevant for advanced-stage patients for whom standard treatment is ineffective.
The research is published in this week’s Science Translational Medicine (Sci. Transl. Med. DOI: 10.1126/scitranslmed.3003293)