When Insulin Goes Away ...

The very core of LC theory on weight loss is that insulin *causes* fat accumulation through it's action, and basically if we can lower insulin, weight loss occurs.  Sounds simple and straight forward.

From Guyton & Hall's Textbook of Medical Physiology, 11th Edition, p. 966

Insulin Deficiency Increases Use of Fat for Energy

All aspects of fat breakdown and use for providing energy are greatly enhanced in the absence of insulin. This occurs even normally between meals when secretion of insulin is minimal, but it becomes extreme in diabetes mellitus when secretion of insulin is almost zero. The resulting effects are as follows.

Insulin Deficiency Causes Lipolysis of Storage Fat and Release of Free Fatty Acids.

In the absence of insulin, all the effects of insulin noted earlier that cause storage of fat are reversed. The most important effect is that the enzyme hormone-sensitive lipase in the fat cells becomes strongly activated. This causes hydrolysis of the stored triglycerides, releasing large quantities of fatty acids and glycerol into the circulating blood.  Consequently, the plasma concentration of free fatty acids begins to rise within minutes.  This free fatty acid then becomes the main energy substrate used by essentially all tissues of the body besides the brain.

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