Insulin is an anabolic signalling hormone, it stimulates glycogenesis, lipogenesis and protein synthesis (construction of glycogen molecules, lipids, and protein). Insulin causes hypoglycemia when taken in excess by inducing translocation of glut4 transporters to cell surface. When you translocate glut4 to cell surface you increase the number of little transporters that are available to move glucose into the cell, and this can lead to low blood sugar if in high or chronic amounts.

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