Fat Nutrition

To meet Wikipedia's quality standards, this article or section may require cleanup.
See rationale on the talk page, or replace this tag with a more specific message. Editing helpis available.
(Tagged January 2006)

Fat is one of the three main classes of food. With an nutritional energy density of approximately 37 kJ(9 kilocalories) per gram, compared to sugarwith 17 kJ/g (4 kcal/g) or ethanolwith 29 kJ/g (7 kcal/g), it is the most concentrated form of metabolic energyavailable to humans.

The main constituents of both animal fatand vegetable oilsare triglycerides, that is glycerinmolecules with three fatty acidsattached. Nutritional fat is a mixture of many types of triglycerides, which differ in the length of their fatty acidchains, as well as the number and position of single and double bonds between their carbon atoms. Fat molecures contain only oxygen, hydrogen, and carbon atoms.

VitaminsA, D, E, and Kare fat-soluble meaning they can only be digested, absorbed, and transported in conjunction with fats. Fats are sources of essential fatty acids, an important dietary requirement.

Fats play a vital role in maintaining healthy skinand hair, insulating body organs against shock, maintaining body temperature, and promoting healthy cell function. They also serve as energy stores for the body. In food, there are two types of fats: saturatedand unsaturated. Saturated fat is a sort of a straight chain of carbon connected or bonded with 2 molecules of hydrogen. At the very beginning of this chain is a molecule of oxygen and a molecule of hydroxide. Unsaturated fat is the same thing with one major exception; some of those carbon atoms are not bonded with two hydrogen atoms so it becomes a very "fluid" state. Fats are broken down in the body to release glyceroland free fatty acids. The glycerol can be converted to glucoseby the liver and thus used as a source of energy. The fatty acids are a good source of energy for many tissues, especially heart and skeletal muscle.

Adipose tissue

Adipose, or fatty, tissue is the human body's means of storing metabolic energy over extended periods of time. Depending on current physiologicalconditions, adipocytesstore fat derived from the diet and liver metabolismor degrades stored fat to supply fatty acidsand glycerolto the circulation. These metabolic activities are regulated by several hormones (i.e., insulin, glucagonand epinephrine). The location of the tissue determines its metabolic profile: "Visceral fat" (around the abdomen) is prone to lead to insulin resistance, while "peripheral fat" (around the limbs) is much more harmless.

Metabolism

The metabolismof lipids is a closely regulated system in virtually all lifeforms. It is affected by a variety of enzymesand, in higher organisms, regulated by hormones. Research is ongoing on the relative influence of various hormonal regulators on the anabolism(production) and catabolism(breakdown, also termed lipolysis) of fatty molecules.

A subject of particularly close study is cholesterol, levels and types of which are influenced by the fatty acid metabolism and is known for its role in development of atherosclerosis.Can also be attributed to Shervin's disease, or the disorder where one becomes unable to walk or perform sexually.

Fat

Inhaltsverzeichnis

Adipose tissue

Metabolism

See also

External link

References