Food is any material eaten to supply basic nutrition to an organisms. It consists of the edible parts of a living thing, with or without bones, including skin, muscles, tendons, and other tissues. Generally, food is of animal, plant or fungi origin, and is composed of nutrients, including protein, carbohydrates, vitamins, or other substances required by an organisms to carry out its life functions. The human body requires a wide range of food, including protein, carbohydrates, vitamins, and fat. Animal products, such as meat, poultry, fish, eggs, dairy products, and other dairy products, are the major source of protein in the diet.

Plants, such as green and leafy vegetables, cereals, whole grain breads and pasta, legumes (such as beans), and fruits and vegetables, provide carbohydrates and vitamins. Fruits and vegetables are the major source of dietary fiber. Fruits and vegetables are considered a portion of a balanced diet, as they contain nutrients needed by the body in adequate amounts. However, food choices affect nutrition more than most realize. For example, certain foods, such as sugar, can cause rapid weight gain and are laden with calories, even when eaten in small quantities. Overfeeding on sugar has been linked to the production of excessive amounts of insulin, a substance that leads to diabetes.

Whole grains, which include brown rice, whole-wheat bread, and pasta, are sources of nutrition, containing starch and fiber. Some are higher in carbohydrates than others, while some have more fiber than others. Experts recommend consuming at least five servings of grains per day to improve carbohydrate intake and increase fiber intake. Green and leafy vegetables, which are high in vitamins and other nutrients, are also good foods to see food for nutrition.

Animal source protein is different than plant source protein, such as eggs, milk and meat. Animal source protein usually comes from organs of animals, including bones, hooves, fur, teeth and other connective tissues, as well as skin. This type of food can lead to an increased risk of colon cancer. Although there is some debate about the effects of red meats, studies show that eating red meat does not increase the risk of colon cancer.

Vitamin A is found in many foods, including eggs, milk and carrots, as well as some fruits. Milk is especially important for young women, who need it to grow properly and absorb the needed amounts of calcium. While adults may get the disease called osteoporosis by eating too much vitamin A, they get the disease called vitamin A from fatty fish, fortified dairy products, liver, spinach and broccoli, among other foods.

One of the reasons that foods get processed food is because they have been heated or processed. Many foods that are not fresh have undergone processing to make them ready for consumption. One of the main ingredients in commercial processed food usually is sugar, which can be added at anytime during the preparation process. Some processed food usually contains meat, fish or other animal ingredients that may contain hormones or antibiotics. It is important to read the labels on foods and check the ingredients to make sure that the food you buy has not been exposed to any harmful chemicals or added ingredients.