Research

Hormonal

Parathyroid hormone (PTH) mediates the relationship between low Vitamin D and non-energy-expenditure aspects of frailty (slowness, weakness) in men.

For older men with low Vitamin D, high PTH levels might be the actual cause of muscle weakness and slowness. Doctors should check PTH levels, not just Vitamin D, to understand frailty risk.

GoodSupportsMEDIUM confidence
Results suggest that PTH mediates the relationship between 25(OH)D and nonenergy expenditure aspects of frailty.
Michelle Shardell et al. · The Journals of Gerontology Series A · 2009

Why this rating

Strong statistical attenuation of OR when controlling for PTH supports mediation, though causality is cross-sectional.

Source

Association of Low Vitamin D Levels With the Frailty Syndrome in Men and Women

Michelle Shardell et al. · The Journals of Gerontology Series A · 2009

DOI 10.1093/gerona/gln007

cross_sectional · n=1005Cited 170×
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DOI resolved against Crossref · corpus check 2026-06-10

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