Mint

Mint — most commonly peppermint and spearmint — is a fresh herb and the source of menthol, the cooling compound responsible for mint's characteristic sensation. Its effect on the digestive tract is genuinely two-sided, and which side dominates depends on the condition and the form.

In the lower esophageal sphincter, menthol relaxes the muscle that keeps stomach acid from refluxing upward. For people with GERD or chronic heartburn, mint — particularly peppermint tea, mint chewing gum, and after-dinner mints — is a recognized reflux trigger. The same relaxing effect that's bad for the LES is helpful further down the tract, where it eases cramping in IBS.

Reflux risk

Peppermint and spearmint relax smooth muscle generally. For the LES this is a problem: stomach acid moves up into the esophagus more easily, particularly when the stomach is full or when lying down. The classic trigger pattern is a mint or mint tea after a heavy meal followed by going to bed. People with GERD should treat all mint flavorings as suspect and test with a short elimination.

IBS benefit (peppermint oil)

Enteric-coated peppermint oil capsules are one of the best-evidenced over-the-counter treatments for IBS — multiple systematic reviews show meaningful reduction in abdominal pain, bloating, and overall symptom severity compared to placebo. The enteric coating keeps the oil intact until it reaches the small intestine, where it relaxes intestinal smooth muscle and acts as a mild antispasmodic. Doses are typically 0.2–0.4 mL three times daily before meals. People with reflux who try peppermint oil for IBS may worsen their reflux — the trade-off is worth discussing with a clinician.