Calorie Restriction in the Elderly People

which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Excessive calorie intake and subsequent obesity is associated with multiple chronic diseases, including type 2 diabetes melli-tus, hypertension, dyslipidemia, coronary heart disease, stroke, and some types of cancers such as colon cancer, endometrial cancer, and breast cancer (1). Moreover, obesity is an independent risk factor for the disability and premature mortality. However, management of the food intake is much neglected by physicians. Furthermore, it is one of the difficult challenges to effectively motivate patients to change their eating behavior for the maintenance or promotion of health. Among the major barriers to counseling patients, physicians' inadequate confidence and lack of knowledge with regards to the optimal food intake is believed to be the main reason for suboptimal recommendation of life style modification in the daily practice. It has been well established that calorie restriction, defined as a reduction in calorie intake below usual ad libitum intake without malnutrition, slows aging and increases maximum life span in various animal models from yeasts to non-human primates (2). Data from epidemiologic studies also suggest that calorie restriction can have beneficial effects on the factors involved in the pathogenesis of age-associated chronic disease and life expectancy in humans. Residents of Okinawa in Japan are famous for their longevity, high numbers of centenarians, and accompanying low risk of age-associated diseases. Much of the longevity advantage in Okinawa is believed to be related to a healthy lifestyle, particularly the traditional diet, which is low in calories yet nutritionally dense (3). In addition, the participant of biosphere 2 experienced a forced decrease in calorie intake for 18 months because of an unanticipated decrease in food availability. During the period, the participants consumed a low-calorie (1,750-2,100 kcal/d) nutrient-dense diet, which resulted in a marked reduction of cardiometabolic risk factors such as blood glucose level, lipid profile, and blood pressure (4). In addition, data from the Calorie Restriction Society who are practicing calorie restriction showed many of the same alterations in metabolic profile and organ function previously reported in calorie restriction rodents, such as low percentage of body fat, low blood pressures, markedly reduction in plasma cholesterol , increased insulin sensitivity, low plasma concentrations of inflammatory markers, low levels of circulating growth factors , low serum concentrations of T3, and improvement of left ventricular diastolic dysfunction (5, 6). Furthermore, calorie restriction may …