Phloretin

Tier 3 — weak evidence · Antioxidant · Skin · Insulin sensitivity

A dihydrochalcone polyphenol abundant in apple peel and leaves. Phloretin inhibits glucose transporters GLUT1 and GLUT2, moderating post-meal glucose flux. In vitro and animal studies show anti-inflammatory, antioxidant, and potential SIRT1-activating activity. Widely used in topical skincare for antioxidant and melanogenesis-inhibiting properties. Very limited human trial data as an oral supplement. Mechanistically interesting but currently preclinical for most claimed benefits.

Dose: 50–200 mg/day with food