We are interested in known energy balance-related CRC risk or protective factors, including (abdominal) fatness as reflected by BMI and waist circumference, height2,3, physical activity2,4, and early life energy restriction5, and how the CRC risks associated with these factors may be modified by sirtuin 1 (SIRT1), an energy-sensing protein. The gene discussed is SIRT1; the disease is colorectal carcinoma.