Dietary microbes modulate transgenerational cancer risk.

Environmental factors are suspected in the increase of obesity and cancer in industrialized countries but are poorly understood. Here, we used animal models to test how future generations may be affected by Westernized diets. We discover long-term consequences of grandmothers' in utero dietary exposures, leading to high rates of obesity and frequent cancers of lung and liver in two subsequent generations of mice. Transgenerational effects were transplantable using diet-associated bacteria communities alone. Consequently, feeding of beneficial microbes was sufficient to lower transgenerational risk for cancer and obesity regardless of diet history. Targeting microbes may be a highly effective population-based approach to lower risk for cancer. ©2015 American Association for Cancer Research.