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ingestible · for oral health & dental care

Green Tea (Camellia sinensis)

Reviewed by the Nimbera editorial team · Last updated May 2026

Mazur 2021 Japanese Dental Science Review (PMID 33737989) - systematic review and meta-analysis of 18 studies (870 participants); green tea showed medium effect on reducing gingival index (SMD 0.50) and plaque index (SMD 0.54), and large effect on reducing probing pocket depth (SMD 1.02).$5-$15/month for tea bags; $15-$30/month for standardized extract capsules

How to use

Drink 2-4 cups of unsweetened green tea daily, allowing it to swish briefly around the mouth before swallowing. Alternatively use a green tea extract mouthwash or catechin-enriched gel as an adjunct to brushing. Avoid adding sugar. For strongest antioxidant content, steep for 2-3 minutes at 70-80 degrees C (avoid boiling water).

How it works

Green tea polyphenols - primarily epigallocatechin-3-gallate (EGCG) - inhibit bacterial adhesion and biofilm formation by periodontal pathogens, reduce production of collagenase enzymes that break down gum tissue, and neutralize reactive oxygen species that drive periodontal inflammation. Catechins also demonstrate direct antimicrobial activity against S. mutans and Porphyromonas gingivalis.

Where to buy

Any grocery store carries green tea bags (Bigelow, Tazo, Yogi, Harney & Sons). For standardized catechin extract supplements standardized to 50%+ EGCG: NOW Foods, Thorne, or Life Extension. Oral gel formulations are available through some dental suppliers.

Typical cost: $5-$15/month for tea bags; $15-$30/month for standardized extract capsules

Safety notes

Green tea contains caffeine - limit intake if sensitive to stimulants. High-dose catechin supplements (above 800 mg EGCG/day) have been associated with rare liver toxicity; stay within beverage amounts or moderate supplement doses. Tannins in tea can stain teeth with heavy use - rinse with water after drinking. May reduce iron absorption if consumed with iron-rich meals.

Drug & supplement interactions

  • Always tell your doctor or pharmacist about any supplements you take.
  • Interactions can occur with prescription medications, blood thinners, and immunosuppressants.
  • Herbal remedies can affect how the body absorbs or metabolises drugs.
  • Check drugs.com interactions checker before starting.

This information is compiled from primary clinical literature and is for informational purposes only. It is not a substitute for professional medical advice. Read our full disclaimer.