About Peppermint
Active is L-menthol (≥50% of peppermint oil), a TRPM8 agonist that relaxes GI smooth muscle and modulates visceral pain signaling. Strong RCT evidence for IBS: Khanna et al. 2014 meta-analysis (9 RCTs, n=726) found NNT=3 for global IBS symptom improvement; Alammar et al. 2019 meta-analysis (12 RCTs, n=835) confirmed significant reduction in abdominal pain and global symptoms. Enteric coating is essential — non-enteric oil triggers heartburn via lower esophageal sphincter relaxation. Also has moderate evidence for tension headache (topical menthol) and post-operative nausea. SAFETY: heartburn and reflux without enteric coating, anal/perianal burning (peppermint oil is excreted partially unchanged). Avoid in GERD, hiatal hernia, and infants/young children (menthol can trigger laryngospasm).
What Peppermint supports
- Strong evidence for IBS symptom relief — enteric-coated oil, NNT~3
- Topical menthol reduces tension headache intensity
- Non-enteric oil triggers heartburn; avoid in GERD and infants
How much Peppermint to take
The RDA prevents deficiency. The effective range is what clinical trials used to actually move the outcome.
Effective
180–675
mg
Enteric-coated peppermint oil 180–225 mg taken 2–3× daily (total 360–675 mg/day) is the clinically validated dosing for IBS in modern RCTs and meta-analyses. Whole-leaf powder doses are less standardized and likely less effective for IBS-specific outcomes.
Clinical evidence
Strong clinical evidence. Two large IBS meta-analyses (Khanna 2014, Alammar 2019) showed NNT~3 for global symptom relief with enteric-coated peppermint oil 180–225 mg TID.
Examine.com