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The main cause for diabetes is lack of insulin in the body. Insulin is the hormone that allows body cells to absorb glucose from the blood. With out insulin, the body cells can't get glucose from the blood. So, why doesn't diabetes cause death by starvation?

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I mean, the short answer is "it does". But on a cellular level, and unevenly. So the effects are a little different. Most of this stuff happens with regular starvation also:… – Resonating Jun 27 '14 at 16:28

Not all cells depend on insulin to take in glucose from blood (e.g. vascular endothelial cells). But the majority do (muscle tissue and fat tissue).

The lack of insulin causes the cell to use auxiliary metabolic pathways to generate its energy [1]:

  • in muscle, the protein breakdown is stimulated
  • liver gluconeogenesis is stimulated by low insulin levels and high amino acid levels in blood and using substrate from muscle and fat tissue
  • glucocorticoids stimulate lipolysis
  • liver starts ketone body synthesis, which along with medium chain fatty acids prove to be quite a good alternative energy source for the brain

Energy from nutritional principles is as follows:

  • Lipids = 9 kcal/g
  • Proteins = 4 kcal/g
  • Carbohydrates = 4 kcal/g - the most important because they are used as is. Lipids and proteins require energy from other sources to start chemical reactions which yield energy.


  1. Mark Brandt, Ph.D. Endocrine Notes Supplement from Rose Hulman Institute of Technology, pages 78-80
  2. Wikipedia (links)
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