It’s been suggested that capsaicin-rich foods like cayenne pepper can help with weight loss by increasing the metabolic rate, possibly by stimulating adrenaline release and promoting thermogenesis.^[35] However, clinical trials on the topic do not consistently support this hypothesis, with a number of studies finding no effect of consuming capsaicin or chili peppers on daily energy expenditure.^[36] Some studies have found that capsaicin-containing supplements increase the number of calories burned after a single meal,^[37] but it’s not clear that this one-time increase in calorie burning is maintained over the long term. Furthermore, capsaicin supplementation does not seem to produce meaningful weight loss, suggesting that any effects on the metabolic rate are clinically insignificant.^[4]

Despite occasional claims that spicy foods can “irritate” the stomach, thereby promoting stomach ulcer development, there is no human evidence linking spicy foods to a higher risk of ulcers, nor is there good reason to think that capsaicin causes damage to the stomach lining.^[26] Eating spicy food might cause abdominal pain in people with an existing ulcer, but this doesn’t mean spicy food is actually making the problem worse.^[27]

A clinical trial from 1987 is sometimes cited as evidence that spicy food can damage the stomach. The study administered various doses of chili pepper powder to a group of 8 participants, reporting a small increase in stomach bleeding after ingestion of 100 milligrams of chili pepper powder.^[28] However, there are a few reasons to be skeptical of this finding. For one thing, no clear increase in stomach bleeding was observed following consumption of higher doses of chili pepper powder (0.5 grams, 1 gram, or 1.5 grams). It seems fairly implausible that higher doses would have no observable effect on stomach bleeding, yet a low dose would have such an effect. Additionally, the study measured stomach bleeding using a chemical technique that appears not especially reliable.^[29]

Some research even suggests that spicy food might protect against the development of stomach ulcers. A few small studies found that people with ulcers eat spicy food less often, not more often (as would be expected if spicy foods cause ulcers).^[30][31] And while this could just be because spicy foods aggravate ulcers (leading people with ulcers to avoid them), a few clinical trials have found that capsaicin seems to protect the stomach’s mucous membrane from damage caused by alcohol and certain nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin.^[32][33]

Still, there is limited evidence looking at how capsaicin interacts with H. pylori infection, which is believed to be responsible for most cases of stomach ulcers. Although some evidence suggests capsaicin might actually inhibit H. pylori growth,^[31][34] more research is needed to determine whether capsaicin has an effect, positive or negative, on ulcer development related to H. pylori infection.

If you're a chili enthusiast with a penchant for peppers, you’ve likely found yourself on the receiving end of a meal that exceeded your tolerance for spice. When that unpleasant burning sets in, a natural reaction will be to reach for a drink to try and tamp down the blaze. But what beverage is best to soothe the scald?

Plain water eases the burning from spicy foods.^[38][38][39] Colder water seems to result in greater relief, possibly because the cold inhibits heat receptors activated by capsaicinoids.^[40]

Milk tends to provide more relief than water.^[39][41][38] This effect seems attributable to a protein in milk called casein, likely because casein can bind to capsaicin, helping to neutralize it.^[41] However, the overall effect of milk is not large, meaning drinking milk will often provide only a small amount of additional relief (and sometimes none at all^[42]) compared to just drinking water.

Beverages with sugar can provide relief from the burning.^[42][39] According to one theory, the activation of sweetness receptors on the tongue inhibits the receptors responsible for spiciness. In at least one study, milk with sugar provided additional burning relief compared to the two components separately.^[39]

Alcoholic beverages have been suggested to help reduce the burning sensation caused by spicy food because capsaicin is soluble in alcohol. However, one of the few experiments to test this found that water with 5% ethanol (comparable to the average beer) provided no additional relief compared to regular water.^[39]