food

Anything eaten by human beings and other animals, or absorbed by plants, to sustain life and health. The building blocks of food are nutrients, and humans can utilize the following nutrients: carbohydrates as starches found in bread, potatoes, and pasta; as simple sugars in sucrose and honey; and as fibres in cereals, fruit, and vegetables; proteins from nuts, fish, meat, eggs, milk, and some vegetables; fats as found in most animal products (meat, lard, dairy products, fish), also in margarine, nuts and seeds, olives, and edible oils; vitamins, found in a wide variety of foods, except for vitamin B₁₂ which is found mainly in foods of animal origin; and minerals, found in a wide variety of foods (for example, calcium from milk and broccoli, iodine from seafood, and iron from liver and green vegetables).

Food is needed both for energy, measured in calories or kilojoules, and nutrients, which are converted to body tissues. Some nutrients, such as fat, carbohydrate, and alcohol, provide mainly energy; other nutrients are important in other ways; for example, fiber is an aid to metabolism. Proteins provide energy and are necessary for building cell and tissue structure.

Liquids consumed are principally water, ubiquitous in nature, and alcohol, found in fermented distilled beverages, from more than 40% in liquor to 0.01% in low-alcohol beers.