Cayenne Pepper
Also known as: Capsicum annuum, capsaicin, red chili pepper, hot pepper
Effective Dosage
No established dose from provided studies
What the Science Says
Cayenne pepper is a common culinary spice whose active compound, capsaicin, is marketed for its supposed fat-burning and metabolism-boosting effects. One clinical trial found that 500 mg of cayenne (delivering 1.25 mg capsaicin) did not significantly increase energy expenditure or fat oxidation at rest or during exercise compared to placebo. A separate study using cayenne as part of a multi-ingredient blend showed some trends toward increased fat oxidation, but the effect could not be attributed to cayenne alone. There is also early, limited evidence that cayenne may act as a prebiotic for beneficial gut bacteria, though this did not produce significant microbiome shifts in a small human trial.
What It Doesn't Do
Won't meaningfully boost your metabolism on its own. No evidence it burns fat at typical supplement doses. Can't be credited for results seen in multi-ingredient blends. Not proven to suppress appetite in humans. No solid evidence it shifts your gut microbiome.
Evidence-Based Benefits
Cayenne pepper contains capsaicin, which has been shown to have potential benefits for weight management by increasing metabolism and promoting fat oxidation. Some studies suggest it may also help reduce appetite, although results can vary.
Moderate EvidenceEffective at: 30-120 mg daily
Source: auto-research
Absorption & Bioavailability
Unknown — no pharmacokinetic data provided in the available studies. Capsaicin absorption varies by formulation and individual tolerance.
Red Flags to Watch For
- Most cayenne research uses multi-ingredient products, making it impossible to isolate cayenne's specific effect
- The only single-ingredient cayenne clinical trial in this dataset found no thermogenic or fat-oxidation benefit
- Cayenne pepper contains trace inorganic arsenic; while levels in one study were below regulatory limits, heavy or long-term use warrants caution
- Gastrointestinal irritation is a known concern with capsaicin-containing supplements, especially at higher doses
- A fenugreek-fiber formulation was needed in one safety study to reduce GI side effects of capsaicinoid-rich chili — suggesting raw cayenne supplements may cause digestive discomfort
Products Containing Cayenne Pepper
See how Cayenne Pepper is used in these analyzed products:
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-06