Chronobiology and chrononutrition: Relevance for aging

Abstract

Abstract Chrononutrition is the science that investigates the correlations between mealtimes, metabolism, physiology, and endogenous circadian rhythms, but it also outlines a diet in harmony with biological biorhythms, one of the main processes that is involved in healthiness, causing, if altered, many diseases and syndromes associated with the aging process. These rhythms originate in the hypothalamic suprachiasmatic nucleus (SCN), located in the anterior hypothalamus, and it is mainly controlled by the oscillations, an important type of cellular signaling characterized by the periodic change of the system over time. The oscillation originating in the suprachiasmatic nucleus (SCN) is known as the central oscillator, and all other similar signals are named peripheral oscillations. These rhythms are not only regulated by these endogenous signals, but it may be entrained by external signals named zeitgebers, such as light, exercise, and meal times. The worst outcome of the deregulation of the physiological circadian rhythms is chronodisruption, which consists of desynchronization of peripheral oscillators from the central one. Some causes of this phenomenon are night work and jet lag, including social jet lag, for example, the discrepancy in a person s sleep pattern between the weekday and the weekend which, if continued chronically, have been associated with an increased risk of metabolic syndrome, obesity, and cardiovascular disease, all pathological conditions associated with aging. Both a low-calorie diet and the regular use of functional and mimetic compounds could be the nutritional basis for promoting health in aging, obviously only together with all the other measures that characterize a correct lifestyle. The optimal diet model for that is the one inspired by the food choices typical of the Mediterranean model with oriental influences and adopt a calorie intake that, depending on the proposed diet, provides a quantity of calories that is between a range of 15%–20% around the basal metabolic rate in subjects with a low level of physical activity. Furthermore, an optimal diet should provide a protein content of around 0.95–1\xa0g/kg body weight and follow all other recommendations published by international nutrition companies. This chapter discusses what is currently known about genetics and physiology of the circadian rhythms and zeitgebers, as well as the main evidence regarding the chronodisruption correlations with obesity, metabolic syndrome, and cardiovascular diseases. Furthermore, here we try to gather chrononutrition main aspects with the best dietary regime for ensuring a successful aging.