Research

Hormonal

Daily vitamin D supplementation (800-1000 IU) improves muscle strength, gait, and reduces fall risk in elderly and frail populations, whereas large intermittent high doses are ineffective.

If you are elderly or frail, take 800-1000 IU of Vitamin D daily. Do not rely on large, infrequent 'bolus' doses (like 150,000 IU every few months) as they do not improve muscle strength or prevent falls effectively. Consistency is key to maintaining the muscle benefits.

GoodQualifiesHIGH confidence
Overall, data from RCT and meta-analysis support a positive effect of daily vitamin D supplementation on muscle function, especially in older individuals with vitamin D insufficiency/deficiency at baseline. A daily dose of 1000 UI appears to be sufficient to obtain significant improvements. In contrast, large intermittent doses of vitamin D do not appear to be efficient at improving muscle strength.
Matthieu Halfon et al. · BioMed Research International · 2015

Why this rating

Based on multiple RCTs and meta-analyses cited, though some conflicting results exist regarding dose frequency.

Source

Vitamin D: A Review on Its Effects on Muscle Strength, the Risk of Fall, and Frailty

Matthieu Halfon et al. · BioMed Research International · 2015

DOI 10.1155/2015/953241

narrative_reviewCited 261×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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