Holy basil (Tulsi)

Tier 3 — weak evidence · Adaptogen · Stress · Glucose

A revered Ayurvedic adaptogen consumed as tea for centuries. Small trials show modest reductions in stress, blood sugar, and cholesterol, but study quality is generally low. May slow blood clotting and interact with diabetes and thyroid medications. Generally considered safe as a tea, but concentrated extracts require more caution.

Dose: 300–600 mg/day extract or 2–3 cups tulsi tea; caution with blood-thinning drugs