Red pepper: vitamin C in the sweet one, little proof for the hot one

Two different foods share the name red pepper, and the evidence splits along the same line. The sweet red bell pepper is where the vitamin C is. USDA samples average 141.7 mg per 100 g and range from 116 to 220.5, so one regular pepper of 120 g carries about 170 mg on that average. We found no trial of the sweet pepper itself. Every randomised study on this page tested hot red pepper as a spice or as capsaicin, the compound that makes chilli burn. Those trials came back flat. Across 13 of them in 821 people, LDL, HDL, blood sugar and HbA1c showed no significant change. Across 24 randomised studies, hot pepper did not raise calorie burning by a significant amount, so the fat-burning pepper is a story the data does not carry. The one absorption study gave 9 people paprika oleoresin, a concentrated extract, which is a different thing from eating the vegetable.

How much is actually in it

• Raw red bell pepper averages 141.7 mg vitamin C per 100 g in USDA Foundation data, but the 9 samples ranged from 116 to 220.5 mg, and the UK table gives 126 mg. — Peppers, bell, red, raw (FDC 2258590, Foundation, 9 samples) and Pepper, capsicum, red, raw (CoFID 13-524) (n = 9 samples) Evidence E source
  Vitamin C 141.7 mg/100 g (range 116.0-220.5, median 130.0) vs CoFID 126 mg, potassium 212.7 (162.0-368.5) vs 216 mg

What a real portion looks like

• One regular raw red pepper weighs 120 g in the US survey database and carries about 170 mg vitamin C, and a cup of 150 g about 213 mg. — Peppers, sweet, red, raw (FNDDS 2709801) portions Evidence E source
  1 regular 120 g = 170.0 mg vitamin C, 1 cup 150 g = 212.6 mg, 1 ring 10 g = 14.2 mg

What your body absorbs

• In 9 volunteers given paprika oleoresin, beta-carotene, beta-cryptoxanthin and zeaxanthin reached the blood, but the red pepper pigments capsanthin and capsorubin were barely absorbed despite a 35 mg capsanthin dose. — 9 fasting volunteers, single dose of paprika oleoresin, chylomicron carotenoids measured (n = 9) Evidence C source
  Capsanthin 35.0 mg and capsorubin 2.0 mg dose, very low bioavailability, provitamin A carotenoids detectable

What cooking and storage change

• By the USDA retention table for vegetables, boiling in covering water and draining keeps about 75% of vitamin C, while baking, frying or using the cooking water keeps about 85%. — USDA Table of Nutrient Retention Factors Release 6, group Vegetables and Vegetable Products, other vegetables Evidence E source
  Vitamin C retained: boiled water cover drained 75%, boiled little water drained 80%, baked 85%, fried 85%, boiled water used 85%

What it does to your health

• A meta-analysis of clinical trials found that hot red pepper or capsaicin changed systolic blood pressure by 0.43 mmHg and heart rate by -0.60 bpm, neither significant. — Clinical trials of red pepper or capsaicin consumption, searched to August 2020 Evidence A source
  SBP +0.43 mmHg (95% CI -1.15 to 2.01), DBP -0.45 mmHg (95% CI -2.14 to 1.24), HR -0.60 bpm

What people believe that the data does not support

• Across 24 randomized studies of culinary doses of hot red pepper, extra calorie burning did not reach significance in one-meal or long-term studies, only fat oxidation shifted, so the fat-burning pepper idea is overstated. — 22 publications, 24 randomized controlled studies, including 24-h respiratory chamber studies (n = 24 studies) Evidence A source
  Energy expenditure change not significant, respiratory quotient consistently lower in long-term studies

Who this works differently for

• In 2,451 older adults, eating sweet peppers 2-3 times a week or more was linked with 34% lower odds of sarcopenia than almost never eating them. — 2,451 older adults, general population, food frequency questionnaire (n = 2451) Evidence C source
  Sweet pepper OR 0.73 (0.56-0.96) for <=1 time/week and 0.66 (0.45-0.95) for >=2-3 times/week

What is still unknown

• For hot red pepper or capsaicin, a 2026 meta-analysis of 13 randomized trials in 821 participants found no significant effect on LDL, HDL, blood glucose or HbA1c. — Adults in 13 placebo-controlled RCTs of capsaicin, red pepper or related compounds (n = 821) Evidence A source
  No significant effect on TG, LDL, HDL, SBP, glucose, insulin, HOMA-IR or HbA1c

The bottom line

Buy red peppers for the vitamin C and because you like them. The amount moves more than a label suggests. Nine USDA samples ranged from 116 to 220.5 mg per 100 g, and the British food table lists 126 mg, so read any single number as a middle value. The composition table near the top of this page comes up empty, and that is a matching fault on our side rather than missing data. The numbers here are read from the USDA Foundation record for peppers, bell, red, raw, and from the British table, neither of which our cohort table picks up under this name. Cooking costs some of it. The USDA retention table for vegetables as a group puts boiling in plenty of water and pouring it away at about 75 percent kept, and baking, frying or keeping the cooking liquid at about 85 percent. That factor was set for the whole group and never measured on peppers. In a survey of 2,451 older adults, those who ate sweet peppers two or three times a week or more had 34 percent lower odds of sarcopenia, the loss of muscle with age, than those who almost never ate them. That survey looked at one moment in time. It cannot tell whether peppers helped the muscle or healthier people simply ate more peppers. In pooled trials, hot red pepper and capsaicin did not change blood pressure: systolic pressure shifted by 0.43 mmHg and heart rate by -0.60 beats a minute, neither significant. Very little of the red pigment reached the blood. When 9 volunteers took paprika extract with 35 mg of capsanthin, the pigment that makes the pepper red, beta-carotene and two related pigments showed up in the blood in real amounts, and capsanthin barely did. It was one small study without a control group, run on an extract, so it says something about the pigments and little about the whole vegetable. One section is missing from this page. We have no evidence card on who should be careful with red pepper: no upper limit, no allergy data and no drug interaction tied to this food. Our interaction data is organised by nutrient, so it cannot answer for a vegetable. Read that as a gap in what we have checked. It is no promise that the pepper suits everyone, and if you take regular medication or have a condition your doctor watches, their advice counts for more than this page.

Sources

1. rpp-b3-06 · reference dataset
   Peppers, bell, red, raw (FDC 2258590, Foundation) - Vitamin C 141.7 MG - range 116.0-220.5 (median 130.0), samples 9 | Pepper, capsicum, red, raw (CoFID 13-524) - Vitamin C 126 mg
   USDA FoodData Central Foundation record 2258590 and CoFID 2021 (Public Health England, OGL v3.0) code 13-524 · checked 2026-09-23
2. rpp-b3-07 · reference dataset
   Peppers, sweet, red, raw (FNDDS 2709801) - Vitamin C 141.7 MG per 100 g - 1 regular 120 g 170.0 MG - 1 cup 150 g 212.6 MG - 1 ring 10 g 14.2 MG
   USDA FNDDS food 2709801 portions · checked 2026-09-23
3. rpp-b3-05 · uncontrolled human absorption study
   From the major carotenoids present in the paprika oleoresin only zeaxanthin, beta-cryptoxanthin and beta-carotene were detectable in considerable amounts...The bioavailability of the pepper-specific carotenoids capsanthin and capsorubin from paprika oleoresin is very low.
   Br J Nutr, 2003 · checked 2026-09-23
4. rpp-b3-08 · reference dataset
   USDA-RETN-R6:3775 VEG,OTHER,BLD,WATER COVER,DRAINED vitamin C 75% | USDA-RETN-R6:3774 VEG,OTHER,BLD,LITTLE WATER,DRAINED 80% | USDA-RETN-R6:3771 VEG,OTHER,BAKED 85% | USDA-RETN-R6:3780 VEG,OTHER,FRIED 85% | USDA-RETN-R6:3776 VEG,OTHER,BLD,WATER USED 85%
   USDA Table of Nutrient Retention Factors, Release 6 (2007) · checked 2026-09-23
5. rpp-b3-02 · meta-analysis of clinical trials
   Meta-analysis showed no significant effect of red pepper/capsaicin on SBP (0.43 mmHg, 95% CI: -1.15 to 2.01), DBP (-0.45 mmHg, 95% CI: -2.14 to 1.24), and HR (-0.60 bpm, 95% CI: -1.97 to 0.78).
   Phytother Res, 2021 · checked 2026-09-23
6. rpp-b3-03 · meta-analysis of RCTs
   Twenty-two publications representing 24 randomized controlled studies were synthesized...One-meal studies showed that EE (diet-induced thermogenesis) and RQ changes did not reach statistical significance. Long-term studies revealed that EE changes did not reach statistical significance, whereas RQ was consistently lower
   Nutr Rev, 2026 · checked 2026-09-23
7. rpp-b3-04 · cross-sectional
   the odds ratios (95% confidence intervals) for sarcopenia across chili and sweet pepper consumption categories were 1.00 (reference) for almost never, 0.73 (0.55, 0.97) and 0.73 (0.56, 0.96) for ≤1 time/week, 0.60 (0.39, 0.90) and 0.66 (0.45, 0.95) for ≥2-3 times/week
   Aging (Albany NY), 2021 · checked 2026-09-23
8. rpp-b3-01 · meta-analysis of RCTs
   Thirteen RCTs (n = 821 participants) were included...However, no significant effects were observed on TG, LDL, HDL, SBP, glucose, insulin, HOMA-IR, or HbA1c.
   Nutr Metab Cardiovasc Dis, 2026 · checked 2026-09-23