Thermogenesis

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Thermogenesis is the process of heat production in organisms. It occurs mostly in mammals, but a few species of thermogenic plants exist.

1 Types
- 1.1 Shivering
- 1.2 Non-shivering thermogenesis
2 Artificial thermogenesis
3 External links

[edit] Types

Depending on whether they are initiated through locomotion and intentional movement of the muscles, thermogenic methods can be classified as one of the following:

Exercise-associated thermogenesis (EAT)
Non-exercise-associated thermogenesis (NEAT)

[edit] Shivering

One method to raise temperature is through shivering.

[edit] Non-shivering thermogenesis

Non-shivering thermogenesis usually occurs in brown adipose tissue (brown fat) that is present in human infants and hibernating mammals. It is a process whereby substances such as free fatty acids (derived from triacylglycerols) remove purine (ADP, GDP and others) inhibition of thermogenin (uncoupling protein-1) which causes an influx of H+ into the matrix of the mitochondria and bypasses the ATP synthase channel. This uncouples oxidative phosphorylation and the energy from the proton motive force is dissipated as heat rather than producing ATP from ADP.

The low demands of thermogenesis mean that they draw, for the most part, on lipolysis as the method of energy production.

[edit] Artificial thermogenesis

Thermogenesis can also be achieved by artificial means. It is becoming common for people to use thermogenic substances to help control fluctuation in weight. The process works by increasing the body's metabolism, thereby increasing its core temperature. Thermogenics are commonly made up of ephedra, bitter orange, capsicum, ginger and caffeine.

Bodybuilders are the most common users of thermogenics, but the drugs are entering the mainstream of the dieting industry.