Nutrition helps understand physiological body processes for the maintenance, growth, reproduction, health, and disease of an organism. Health is the social, emotional, and mental well-being of the organisms. Maintenance and good health constitute various physical, mental, and social factors. Aging is the gradual physical, psychological, and social change that leads to weakness, disease, or death. It includes oxidative stress, glycation, telomere shortening, side reactions, and mutations, causing progressive damage to the structure and functions of cells.