MSM / Methylsulfonylmethane for Skin Health
There is only weak, conflicted evidence that oral MSM (methylsulfonylmethane) improves skin aging, so it cannot be considered a proven way to reduce wrinkles or boost skin elasticity. Every human trial showing a benefit was paid for by the same supplement manufacturer, and Europe's food-safety regulator has formally rejected MSM's skin and collagen claims.
Why this grade7-layer evidence engine
Four small randomized trials (n=20 to 83, run for 16 weeks or less) reported that 1-3 g/day of MSM modestly improved wrinkles, firmness, and elasticity versus placebo (p<0.05). On paper that looks encouraging, but the quality is low: every trial was funded by Bergstrom Nutrition, the maker of the branded OptiMSM ingredient, and at least one author holds related patents. Two of the four studies were never even indexed in PubMed.
The signal also doesn't isolate MSM cleanly. One trial (PMID 31119010) tested MSM blended with hyaluronic acid and L-carnosine, so the skin gains can't be pinned on MSM. In another, the MSM-only group failed to improve elasticity; elasticity only moved when MSM was combined with collagen. The most rigorous-looking study (PMID 32083522) was double-blind but came from the same conflicted source. There is no independent, academic, or government-funded trial and no meta-analysis.
Outside sources are unconvinced. Europe's EFSA rejected MSM's health claims, including normal collagen formation; the US FDA only grants it GRAS food-safety status, not any efficacy claim; and Examine, Mayo Clinic, Cleveland Clinic, Harvard Health, and the AAD offer no endorsement for skin. The heavy conflict of interest caps this at a weak grade. For skin, the well-proven basics remain daily broad-spectrum sun protection and regular moisturizing.
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditable▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.503
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 無高階證據可裁決
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status