Beauty-from-within supplements have gained solid RCT support for specific outcomes β wrinkle depth, nail brittleness, hair density β when correctly formulated.
- Hydrolyzed collagen peptides (10β15 g/day): Multiple meta-analyses confirm improvements in skin elasticity, hydration, and wrinkle depth after 8β12 weeks.
- Biotin (2.5β5 mg/day): Well-supported for brittle nails. Less evidence for hair growth in biotin-replete individuals.
- Silica (as MMST, 5β10 mg/day): Small RCTs show improvement in nail and hair strength.
- Zinc (15β30 mg/day): Deficiency causes hair loss, skin issues, and slow wound healing.
- Hyaluronic acid (120β240 mg/day): Small RCTs show skin hydration improvements.
- Vitamin C (500β1000 mg/day): Cofactor for collagen synthesis.
- Non-hydrolyzed collagen (poor absorption)
- Proprietary "beauty blends" hiding individual doses
- Mega-dose biotin (>5 mg) can interfere with thyroid and cardiac lab tests
- Unspecified collagen sources (look for marine, bovine, or chicken on the label)
Collagen type and hydrolysis quality (type I+III for skin, type II for joints), dose fidelity to RCTs, bioavailability enhancers where relevant, and third-party testing. We also value transparency on collagen source and manufacturing.