The term food refers to any material processed for human consumption that is used to provide nutrition to an organism. In the simplest terms, food is any material prepared or consumed for human consumption that is capable of providing the necessary nutrients required by the body to maintain its physical health. Food is generally of animal, plant or even fungal origin and comprises necessary nutrients, including vitamins, proteins, carbohydrates, and minerals. Since humans are a complex organism comprised of different types of cells (both protonemically and alkaliphilic), each cell has its own need for nutrient-rich substances that it can use for energy production and regulation. Although these foods are made up of all the fundamental building blocks of the body, the foods themselves constitute a major component of the human body with the remainder composed of vital organs and tissues.
A major component of food is protein, with egg being the most significant source of protein in comparison with other proteins. Milk products are also major contributors to dietary protein, together accounting for about 50% of total calories consumed by the average individual in the United States. Other major food ingredients include fat, sugar, salt, vegetable protein, flavorings and herbs. Some food additives, such as sodium benzoate (used to preserve food), are recognized health risks because they have been shown to result in cancer in studies with laboratory animals.
Food nutrition refers to the study of how diets rich in food contribute to the daily intake of nutrients needed by the body for normal physical activity, growth and development, maintenance and repair of tissues and organs, and for the elimination of waste products. The goal of healthy nutrition is to see food eaten on a regular basis and to see food additives as something beneficial to health when consumed in reasonable amounts. When seen in this way, food becomes not just a means of sustenance but also a means of enhancing the body’s ability to resist or even cure disease. Nutrient dense diets are important for individuals who want to lead a healthy lifestyle.