Research

Hormonal

Short-term vitamin D3 supplementation (120,000 IU every two weeks for 6 weeks) improves postprandial insulin sensitivity (measured by OGIS) in centrally obese, non-diabetic men, but does not affect fasting insulin sensitivity, lipid profiles, or blood pressure.

If you are a centrally obese man over 35 with low vitamin D, taking 120,000 IU of Vitamin D3 every two weeks for six weeks may help your body handle sugar after meals better. However, do not expect this to lower your fasting blood sugar, improve your cholesterol, or lower your blood pressure. It is a targeted intervention for postprandial sensitivity, not a general metabolic fix.

GoodQualifiesHIGH confidence
The trial indicates that vitamin D3 supplementation improves postprandial insulin sensitivity (OGIS) in apparently healthy men likely to have insulin resistance (centrally obese but non-diabetic)... No changes in secondary outcome measures (insulin secretion, basal indices of insulin sensitivity, blood pressure or lipid profile) were found with supplementation.
Jitender Nagpal et al. · Diabetic Medicine · 2008

Why this rating

Double-blind, randomized, placebo-controlled trial (RCT) with a reasonably large sample size for the setting, though limited by short duration and drop-out rate.

Source

A double‐blind, randomized, placebo‐controlled trial of the short‐term effect of vitamin D<sub>3</sub> supplementation on insulin sensitivity in apparently healthy, middle‐aged, centrally obese men

Jitender Nagpal et al. · Diabetic Medicine · 2008

DOI 10.1111/j.1464-5491.2008.02636.x

rct · n=100Cited 312×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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