Vitamin D: The Metabolic Master Key for Blood Sugar Control

Vitamin D receptors are on your pancreatic beta cells, the cells that make insulin. They are on your immune cells, the muscle cells, the bone cells. As a metabolic hormone, it affects insulin secretion, insulin sensitivity, immune function, muscle strength, and mood. So it does a lot more than just bones. For diabetes and pre-diabetes specifically, a meta-analysis of 18 randomized trials showed that vitamin D supplementation improved fasting insulin, fasting glucose, and insulin resistance. But the benefits are concentrated in people who are actually deficient, not randomly taking diabetes replacement. This is the theme: replace what is missing. Do not mega-dose what is already out there. The big finding for prediabetes— this is the one I quote all the time— comes from an individual participant data meta-analysis of 3 major trials, over 4,000 patients. Vitamin D reduced progression from prediabetes to diabetes by 15% overall. Jaiwant Rangi.