Moderately reducing caloric intake over a period of two years significantly improved cardiometabolic risk factors in young and middle-aged, non-obese adults, according to findings from the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) trial. The study is a multicenter, randomized, controlled trial supported by the National Institute on Aging (NIA) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health.
 
According to the researchers, there are no pharmacologic agents with such profound effects on such a broad range of cardiometabolic risk factors. The study published online July 11, and will appear in the September print edition of The Lancet Diabetes & Endocrinology. The paper was authored by a team led by CALERIE study principal investigator William E. Kraus, MD, of Duke University School of Medicine, Durham, North Carolina.
 
Compared to the control group, the calorie restriction group experienced significant reductions in multiple cardiometabolic risk factors, including waist circumference, blood pressure, HDL cholesterol, LDL cholesterol, triglycerides, insulin sensitivity and fasting glucose, and C-reactive protein (a marker of systemic inflammation associated with multiple chronic conditions and diseases of age).
 
Calorie restriction was found to improve risk factors for the development of atherosclerotic cardiovascular disease and related deaths well below clinical risk thresholds. This speaks to the impact that the dietary practice might have, even when adopted by younger people in good health.
 
CALERIE was the first trial that investigated the effects of two-year caloric restriction in humans, following on evidence from several model organisms showing that calorie restriction increased both health span and life span. Over 200 young and middle-aged normal-weight or moderately overweight adults were randomly assigned to follow either a calorie restriction diet or their usual diets. After two years, participants in the experimental group had reduced their daily caloric intake by 12% and maintained, on average, a 10% loss in body weight.