Every three to five days, all of the cells lining the human intestine are replaced. That constant replenishment of cells helps the intestinal lining withstand the damage caused by food passing through the digestive tract. This rapid turnover of cells relies on intestinal stem cells, which give rise to all of the other types of cells found in the intestine. Recent research has shown that those stem cells are heavily influenced by diet, which can help keep them healthy or stimulate them to become cancerous. “Low-calorie diets such as fasting and caloric restriction can have anti-aging effects and anti-tumor effects, and we want to understand why that is. On the other hand, diets that lead to obesity can promote diseases of aging, such as cancer,” says Omer Yilmaz, PhD, the Eisen and Chang Career Development Associate Professor of Biology at MIT. For the past decade, Dr. Yilmaz has been studying how different diets and environmental conditions affect intestinal stem cells, and how those factors can increase the risk of cancer and other diseases. This work could help researchers develop new ways to improve gastrointestinal health, either through dietary interventions or drugs that mimic the beneficial effects of certain diets, he says. “Our findings have raised the possibility that fasting interventions, or small molecules that mimic the effects of fasting, might have a role in improving intestinal regeneration,” says Dr. Yilmaz, who is also a member of MIT’s Koch Institute for Integrative Cancer Research.