The Surgeon's Verdict
Every claim we've graded
Popular health claims about strength, joints, skin and hair, each graded A to D against the research. Myths first.
| Grade | Claim | Article |
|---|---|---|
| D · Unsupported | Biotin supplements make hair grow in healthy people | Biotin for hair: a popular supplement with a hidden lab-test problem |
| D · Unsupported | Collagen supplements prevent or treat skin aging | Collagen supplements for skin and joints: what the best trials say |
| D · Unsupported | Collagen gives lasting relief from osteoarthritis pain | Collagen supplements for skin and joints: what the best trials say |
| D · Unsupported | Making your grip stronger will make you live longer | Grip strength: the vital sign hiding in your hand |
| A · Strong | Progressive resistance training increases muscle strength in older adults | Grip strength: the vital sign hiding in your hand |
| C · Early | Biotin can help hair or nails when there is biotin deficiency or certain underlying conditions | Biotin for hair: a popular supplement with a hidden lab-test problem |
| C · Early | Pooling all randomized trials, collagen supplements improve skin hydration and elasticity | Collagen supplements for skin and joints: what the best trials say |
| C · Early | Collagen hydrolysate gives clinically important short-term pain relief in osteoarthritis | Collagen supplements for skin and joints: what the best trials say |
| B · Moderate | High biotin levels can interfere with biotin-based lab tests and cause diagnostic errors | Biotin for hair: a popular supplement with a hidden lab-test problem |
| B · Moderate | Trials without industry funding, and high-quality trials, show no effect on skin hydration, elasticity or wrinkles | Collagen supplements for skin and joints: what the best trials say |
| B · Moderate | Weaker grip is associated with higher risk of death from any cause and from cardiovascular disease | Grip strength: the vital sign hiding in your hand |
| B · Moderate | Grip strength predicted all-cause and cardiovascular death better than systolic blood pressure (one multinational cohort) | Grip strength: the vital sign hiding in your hand |
How grades work: our method.
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