Does spicy food (capsaicin) help you lose weight?

Short answer

Barely. Capsaicin burned an extra 34–59 kcal a day and, taken before a meal, cut 74 kcal at that meal, but pooling 15 trials, body weight fell by only 0.51 kg more.

Does spicy food (capsaicin) help you lose weight?
'Spicy → body heats up → fat burns' — does this formula hold?
Spicy food makes you sweat and feel hot. So it is often said that capsaicin, the hot compound in chili peppers, helps you lose weight. We checked, step by step, whether it burns more, makes you eat less, and actually lowers body weight.
The body did burn a bit more
34–59 kcal a day, less than 1/5 of a bowl of rice
An analysis that pooled 13 trials found capsaicin raised the calories burned at rest by 34 kcal a day. Another analysis of 9 trials found 59 kcal a day. That is less than 1/5 of a bowl of rice (about 300 kcal).
And only in short measurements
One-meal and multi-week studies showed no calorie difference
A 2026 analysis of 24 trials published up to 2024 found the extra calories burned showed up only in studies that measured people for 24 hours in a sealed room. Studies of a single meal and studies lasting weeks or longer showed no difference. Only the share of fat the body used as fuel stayed higher.
Does it make you eat less?
Taken before a meal: 74 kcal less at that meal
An analysis that pooled 8 studies (191 people) found that capsaicin before a meal cut intake at that meal by 74 kcal. The effect appeared at 2 mg of capsaicin or more, and food choice shifted from fatty foods toward carbohydrate foods.
So how much weight came off?
15 trials pooled: 0.51 kg
An analysis that pooled 15 trials (762 people) found those who took capsaicin lost 0.51 kg more body weight and 1.12 cm more off the waist than those who did not. It went down, but by less than 1 kg.
Does it keep the weight off?
3 months: it did not stop regain
91 people who had lost an average of 6.6 kg in 4 weeks took 135 mg of capsaicin or a placebo daily for 3 months. Regain was 33.3% with capsaicin and 19.2% with placebo, so capsaicin did not stop the weight coming back. Only fat use as fuel stayed higher.
What about people who eat spicy food often?
Belly fat was actually more common
A survey of 40,877 people in China's Sichuan Basin found those who ate spicy food 6–7 days a week had 1.25–1.35 times the risk of belly fat above the cutoff compared with those who never did. It was measured at one point in time, so it does not mean spicy food caused the belly. But spicy food did not protect against belly fat.
Summary: capsaicin takes off very little weight
Pooled: 0.51 kg; extra burn at most 59 kcal a day
The extra calories capsaicin burned were at most 59 kcal a day, and taking it before a meal cut 74 kcal at that meal. Even so, pooling 15 trials, the weight difference was 0.51 kg. Read spiciness as seasoning, not as a weight-loss tool.