Nutrition is the science that studies how what people eat affects their health and performance, such as foods or food components that cause diseases or deteriorate health (such as eating too many calories, which is a major contributing factor to obesity, diabetes, and heart disease). The field of nutrition also studies foods and dietary supplements that improve performance, promote health, and cure or prevent disease, such as eating fibrous foods to reduce the risk of colon cancer, or supplementing with vitamin C to strengthen teeth and gums and to improve the immune system.Personal health depends partially on the social structure of one’s life. The maintenance of strong social relationships is linked to good health conditions, longevity, productivity, and a positive attitude. This is due to the fact that positive social interaction as viewed by the participant increases many chemical levels in the brain which are linked to personality and intelligence traits. Essentially this means that positive reinforcement from a third party make one more socially adept, in control, and relaxed physically and mentally, all of which are proven to effect the nervous system(UHF).

Sports nutrition:Sports nutrition focuses on how food and dietary supplements affect athletic performance (during events), improvement (from training), and recovery (after events and training). One goal of sports nutrition is to maintain glycogen levels and prevent glycogen depletion. Another is to optimize energy levels and muscle tone. An athlete's strategy for winning an event may include a schedule for the entire season of what to eat, when to eat it, and in what precise quantities (before, during, after, and between workouts and events). Participants in endurance sports such as the full-distance triathlon actually eat during their races. Sports nutrition works hand-in-hand with sports medicine.Exercise A U.S. Marine emerges from the water upon completing the swimming leg of a triathlon.Exercise is the performance of movements in order to develop or maintain physical fitness and overall health. It is often directed toward also honing athletic ability or skill.

Frequent and regular physical exercise is an important component in the prevention of some of the diseases of affluence such as cancer, heart disease, cardiovascular disease, Type 2 diabetes, obesity and back pain.Exercises are generally grouped into three types depending on the overall effect they have on the human body:Flexibility exercises such as stretching improve the range of motion of muscles and joints. Aerobic exercises such as walking and running focus on increasing cardiovascular endurance and muscle density. Anaerobic exercises such as weight training or sprinting increase muscle mass and strength. Physical exercise is considered important for maintaining physical fitness including healthy weight; building and maintaining healthy bones, muscles, and joints; promoting physiological well-being; reducing surgical risks; and strengthening the immune system.Proper nutrition is just as, if not more, important to health as exercise. When exercising it becomes even more important to have good diet to ensure the body has the correct ratio of macronutrients whilst providing ample micronutrients; this is to aid the body with the recovery process following strenuous exercise.

When the body falls short of proper nutrition, it gets into starvation mode developed through evolution and depends onto fat content for survival. Research suggest that the production of thyroid hormones can be negatively affected by repeated bouts of dieting and calorie restriction.

Health

Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.The definition was updated in the 1986 WHO "Ottawa Charter for Health Promotion" to say health is a "resource for everyday life, not the objective of living", and "health is a positive concept emphasizing social and personal resources, as well as physical capacities.". Aspects of Health:"Mens sana in corpore sano" (Juvenal) Physical Health:Physical fitness is good bodily health, and is the result of regular exercise, proper diet and nutrition, and proper rest for physical recovery.A strong indicator of the health of populations is height, which is generally increased by improving nutrition and health care, and is also influenced by the standard of living and quality of life. Genetics is also a major factor in people's height. The study of human growth, its regulators, and its implications is known as Auxology. Mental health:Mental health refers to a human individual's emotional and psychological well-being.

Merriam-Webster defines mental health as "A state of emotional and psychological well-being in which an individual is able to use his or her cognitive and emotional capabilities, function in society, and meet the ordinary demands of everyday life."According to the World Health Organization, there is no one "official" definition of mental health. Cultural differences, subjective assessments, and competing professional theories all affect how "mental health" is defined. In general, most experts agree that "mental health" and "mental illness" are not opposites. In other words, the absence of a recognized mental disorder is not necessarily an indicator of mental health.One way to think about mental health is by looking at how effectively and successfully a person functions. Feeling capable and competent; being able to handle normal levels of stress, maintain satisfying relationships, and lead an independent life; and being able to "bounce back," or recover from difficult situations, are all signs of mental health.

Encompassing your emotional, social, and—most importantly—your mental well-being; All these aspects—emotional, physical, and social—must function together to achieve overall health. Determinants of health:The LaLonde report suggested that there are four general determinants of health including human biology, environment, lifestyle, and healthcare services. Thus, health is maintained and improved not only through the advancement and application of health science, but also through the efforts and intelligent lifestyle choices of the individual and society.A major environmental factor is water quality, especially for the health of infants and children in developing countries. Health maintenance:Achieving health and remaining healthy is an active process. Effective strategies for staying healthy and improving one's health include the following elements: Nutrition: The updated USDA food pyramid, published in 2005, is a general nutrition guide for recommended food consumption.