Research

Hormonal

Higher vitamin D status (serum 25(OH)D) is associated with improved insulin sensitivity and a lower risk of type 2 diabetes, potentially mediated by increased muscle mass, reduced parathyroid hormone (PTH) levels, and enhanced insulin receptor expression.

If you are at risk for diabetes or have been diagnosed with vitamin D deficiency, ensuring adequate vitamin D levels (via sun, diet, or supplementation) may help improve your body's sensitivity to insulin. This is particularly relevant if you have prediabetes. Consult a doctor to check your levels, as deficiency is common and linked to higher diabetes risk.

GoodSupportsHIGH confidence
Vitamin D status, assessed by serum 25-hydroxyvitamin D levels, is inversely associated with diabetes in epidemiological studies. Several clinical intervention studies also support that vitamin D, or its active metabolite 1,25-dihydroxyvitamin D (1,25(OH)2D), improves insulin sensitivity... The mechanisms proposed which may underlie this effect include potential relationships with improvements in lean mass, regulation of insulin release, altered insulin receptor expression and specific effects on insulin action. These actions may be mediated by systemic or local production of 1,25(OH)2D or by suppression of parathyroid hormone, which may function to negatively affect insulin sensitivity.
Dorothy Teegarden et al. · Nutrition Research Reviews · 2009

Why this rating

Strong epidemiological support and some positive intervention studies, though results are mixed and mechanisms are complex.

Source

Vitamin D: emerging new roles in insulin sensitivity

Dorothy Teegarden et al. · Nutrition Research Reviews · 2009

DOI 10.1017/s0954422409389301

narrative_reviewCited 262×
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DOI resolved against Crossref · corpus check 2026-06-10

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