The Research
Straight from the research
Digestive bitters have been used for centuries. Here's where the modern science stands — organized by condition, with notes on the strength of each finding.
Indigestion and Bitters
A review of dandelion and its constituents identified possible pharmacological effects across several GI conditions — including dyspepsia, GERD, gastritis, intestinal ulcer, and ulcerative colitis.
Li Y, Chen Y, Sun-Waterhouse D. J Ethnopharmacol. 2022;293:115272. doi:10.1016/j.jep.2022.115272
Bloating and Bitters
Two bitter taste receptors — TAS2R38 and TAS2R46 — are expressed in human intestinal smooth muscle cells. When activated by bitter compounds, they triggered calcium signaling and faster cell contraction, suggesting a potential role in gut motility and peristalsis. (In vitro)
Shimizu S, et al. Int J Mol Sci. 2025;26(5):2092. doi:10.3390/ijms26052092
Over-fullness and Bitters
The same 2025 receptor study found that bitter compounds activating TAS2R38 and TAS2R46 in intestinal smooth muscle cells accelerated cell contraction — a mechanism plausibly relevant to post-meal heaviness and gastric emptying.
Shimizu S, et al. Int J Mol Sci. 2025;26(5):2092. doi:10.3390/ijms26052092
Reflux / GERD and Bitters
A 2022 review of dandelion noted GERD among the GI conditions where dandelion constituents showed possible pharmacological effects. The authors emphasized this remains mechanistic.
Li Y, Chen Y, Sun-Waterhouse D. J Ethnopharmacol. 2022;293:115272. doi:10.1016/j.jep.2022.115272
Gastritis and Bitters
The same dandelion review listed gastritis among conditions with possible pharmacological effects from dandelion constituents.
Li Y, Chen Y, Sun-Waterhouse D. J Ethnopharmacol. 2022;293:115272. doi:10.1016/j.jep.2022.115272
IBS and Bitters
In a double-blind, randomized, placebo-controlled multicenter trial, two multi-herb bitter formulas (STW5 and STW5-II) significantly reduced both abdominal pain and total IBS symptom scores compared to placebo at 4 weeks.
Madisch A, et al. Aliment Pharmacol Ther. 2004;19(3):271–279. doi:10.1111/j.1365-2036.2004.01859.x
SIBO and Bitters
A clinical review on herbs for upper digestive flora overgrowth noted that bitter and pungent herbs may act as prokinetics and support the migrating motor complex, the between-meal contractions that help clear the small intestine. Prokinetic support is a key mechanism in SIBO management.
Yarnell E. Altern Complement Ther. 2018;24(4):201–206. doi:10.1089/act.2018.29176.eya
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This page is for educational purposes only and does not constitute medical advice. These statements have not been evaluated by the FDA. Amara Bitters is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider with questions about your health.