Protocatechuic acid

Tier 3 — weak evidence · Antioxidant · Cardiovascular · Neuroprotection

A simple phenolic acid metabolite of anthocyanins and gallic acid, found in berries, red wine, and green tea. Protocatechuic acid has potent antioxidant activity, documented cardioprotective effects in animal studies (reduced oxidised LDL, platelet aggregation inhibition), and emerging neuroprotective data. Readily crosses the blood-brain barrier. Primarily studied as a phytochemical marker of whole-food polyphenol consumption, though increasingly present in antioxidant formulas.

Dose: 50–200 mg/day with food