Circadian rhythms, metabolism, and nutrition are closely linked, although the effects of meal timing on the human circadian system are poorly understood. The time factor biological of nature is an essential element for the functioning of cosmic systems. In the event of any defect, many problems come out as a result of this imbalance, and here came whether to change the timing of eating diets has to do with the occurrence of illness in the body and the emergence of diseases of this age such as obesity and diseases of the gastrointestinal tract (gallbladder - diseases of the colon, liver, and others). Hence the need to research the effect of timing, eating the three meals, and the body's system to resist disease. The study sample was withdrawn from Egyptian and foreign guests in hospitality establishments in Hurghada, Egypt with 300 forms. SPSS statistical program was used, and the research was focused on the body's sympathetic nervous system and its role in regulating the body processes related to metabolism. The timing of waking up and eating meals reached a set of findings and recommendations. The most important ones are the need to amend the healthy track of food and to increase the awareness of educational health, followed by hotels and resorts’ restaurants and room services offering those meals according to the client’s demand and the time they want to eat the meal. Therefore, it is necessary to direct the food operators in the hospitality establishments to prepare the food at the optimum time and to search for the modification of new food trends in line with the nature and the regularity of the diet to prevent diseases.