Food is any material eaten to supply nutrition to an organism in the body. Generally, food is of animal, plant or fungi origin, and has necessary nutrients, including protein, vitamins, carbohydrates, and minerals, which are vital for growth and maintenance of an animal or plant. Plants are fed by the earth’s sunlight during daylight hours, while animals get their nourishment from the sun, milk, meat or bone marrow. Fungi are fed by sucking the leaves of certain plants, while animals may eat carrion, insects, seeds, fruits, grains and other plant materials.

During digestion, fat is released from the foods, which is then absorbed into the bloodstream through the stomach and small intestines. The nutrients in fat are then carried out of the body through the blood, which carries them to nearly every organ in the body, where they are used for energy, making the body function normally. While most foods are rich in nutrients, fat is a much more complex source of nutrients that requires the body to break it down, digest it and absorb it into the bloodstream for use.

Fatty acids are essential for life, as they form the major constituent of cell membranes and hormones. However, the absorption of these fatty acids is much more inefficient than the absorption of vitamins and other essential minerals, and these substances become depleted over time. The best dietary sources of fatty acids are nuts, seeds, fish, avocados, olives and olive oil. Although some fats are naturally present in the body in fatty acids produced by the liver or from safflower oils, these foods also contain trans-fats, which are believed to be even more harmful to health than the saturated fats. Oils from tropical plants, such as palm oil, are not bad for you, but palm oil is among the highest in trans-fatty acids.