Bell pepper: a vitamin C vegetable whose health trials used capsules

The strongest numbers anywhere near a bell pepper come from capsules. A meta-analysis of 11 placebo-controlled trials in 609 adults found that Capsicum annuum supplements, mostly capsaicinoid or capsinoid extracts, lowered LDL cholesterol by a standardized mean difference of 0.39 (95% CI 0.07 to 0.72), with a prediction interval that crossed zero. Their effect on body weight did not reach significance. In 4 trials of adults with metabolic syndrome, the same kind of supplement lowered total cholesterol by about 5 mg/dL (95% CI 2.9 to 7.1) and left LDL, HDL and triglycerides unchanged. We found no randomized trial of whole sweet pepper on any clinical outcome. What the vegetable itself delivers is vitamin C. One regular raw red pepper of 120 g gives about 170 mg in the US survey database. UK tables list 126 mg per 3.5 oz (100 g) for red and 120 mg for green, so the figure moves a little between sources.

The numbers, per 3.5 oz (100 g)

How much is actually in it

• Raw red bell pepper provides about 126 mg vitamin C and 580 ug carotene per 3.5 oz (100 g) in UK food tables. — Not applicable (food composition) Evidence E source
  Per 100 g: vitamin C 126 mg, carotene 580 ug, 21 calories, sugars 4.2 g, fiber 2.2 g
• Raw green bell pepper has similar vitamin C (120 mg per 3.5 oz (100 g)) but less than half the carotene of red (265 vs 580 ug). — Not applicable (food composition) Evidence E source
  Per 100 g: vitamin C 120 mg, carotene 265 ug, 15 calories, sugars 2.4 g

What a real portion looks like

• One regular raw red bell pepper (120 g) supplies about 170 mg vitamin C in the US survey database, 142 mg per 3.5 oz (100 g). — Not applicable (food composition) Evidence E source
  1 regular 120 g: 170 mg vitamin C; 1 cup 150 g: 213 mg; per 3.5 oz (100 g) 141.7 mg
• Preschool children ate about 1.1 oz (31 g) more vegetables and fruit when offered a variety such as cucumber, sweet pepper and tomato together rather than one type. — Children aged 3 to 5 years, 61, eight afternoon snacks in childcare (n = 61) Evidence B source
  Intake up 31 g (SEM 5); vegetables 22 g vs fruit 84 g mean intake

What your body absorbs

• In 33 adults taking 20 or 100 mg paprika oleoresin daily for 12 weeks, beta-cryptoxanthin and zeaxanthin rose in blood, capsanthin never appeared, and no adverse events occurred. — Healthy adults, 33, 0, 20 or 100 mg paprika oleoresin daily for 12 weeks (n = 33) Evidence B source
  Dose-dependent plasma beta-cryptoxanthin and zeaxanthin; capsanthin undetected; no adverse events

What cooking and storage change

• Boiling red bell pepper in water lowers its vitamin C from 126 to 89 mg per 3.5 oz (100 g) in UK food tables, about 30% less. — Not applicable (food composition) Evidence E source
  Vitamin C 89 mg boiled vs 126 mg raw per 3.5 oz (100 g); carotene 617 vs 580 ug
• USDA retention factors for vegetables boiled in covering water and drained keep about 75% of vitamin C and 65% of folate. — Not applicable (food composition) Evidence E source
  Vitamin C 75% retained, folate 65%, thiamin 80%
• In a Korean survey of raw vegetables, 18 of 21 Bacillus cereus isolates from bell peppers carried all eight enterotoxin genes. — Retail raw vegetables in Korea, 102 samples (n = 102) Evidence C source
  47% of vegetable samples contaminated; 80% of bell pepper isolates with 8 toxin genes

What it does to your health

• In 4 trials of adults with metabolic syndrome, Capsicum annuum supplements lowered total cholesterol by about 5 mg/dL without changing LDL, HDL or triglycerides. — Adults with metabolic syndrome and related disorders, 4 RCTs (n = 4 RCTs) Evidence A source
  Total cholesterol WMD -4.98 mg/dL (95% CI -7.08 to -2.88)
• Among 2,451 older adults, eating sweet peppers 2 to 3 times a week or more was linked with about one third lower odds of sarcopenia than almost never. — Older adults in a general population, 2,451, food frequency questionnaire (n = 2451) Evidence C source
  Sweet pepper OR 0.66 (95% CI 0.45 to 0.95) for 2-3 times/week or more vs almost never

Safety, limits and interactions

• A 16 year old with lipid transfer protein syndrome had positive skin prick tests to many raw and cooked vegetables and fruits, bell pepper among them. — One adolescent male with mugwort pollinosis (n = 1) Evidence D source
  Positive skin prick tests to heated and non-heated bell pepper

What people believe that the data does not support

• A meta-analysis of 11 trials with 609 people found Capsicum annuum supplements lowered LDL cholesterol modestly, and their effect on body weight did not reach significance. — Adults in 11 placebo-controlled trials of Capsicum annuum supplements (n = 609) Evidence A source
  LDL SMD -0.39 (95% CI -0.72 to -0.07); body weight SMD -0.19 (-0.40 to 0.03)
• In 24 young men doing resistance training, 12 mg daily of capsiate from sweet pepper extract for 10 weeks did not change body fat, appetite or strength versus placebo. — Healthy untrained young men, 24, 10 weeks of resistance training (n = 24) Evidence B source
  No supplementation by time interaction for fat mass, appetite, leptin or strength (P > .05)

Who this works differently for

• Preschoolers who watched peers eat bell pepper on video ate 15.5 g of it a week later versus 5.9 g in controls. — Children aged 3 to 5 years, 42 (n = 42) Evidence B source
  15.5 g vs 5.9 g bell pepper on day 7 (P = .04)

What is still unknown

• After a single dose of paprika extract, only zeaxanthin, beta-cryptoxanthin and beta-carotene reached blood fats in 9 volunteers, while the red pepper pigments capsanthin and capsorubin were barely absorbed. — Healthy volunteers, 9, single dose of paprika oleoresin (n = 9) Evidence C source
  Capsanthin and capsorubin bioavailability very low; provitamin A carotenoids detectable

The bottom line

Green pepper has less than half the carotene of red in UK tables, 265 against 580 ug per 3.5 oz (100 g). The pepper-specific red pigments, capsanthin and capsorubin, barely reach the blood. In 9 volunteers given a single dose of paprika extract, only zeaxanthin, beta-cryptoxanthin and beta-carotene turned up in real amounts. Over 12 weeks of 20 or 100 mg paprika extract a day in 33 adults, beta-cryptoxanthin and zeaxanthin rose with the dose, capsanthin never appeared, and there were no adverse events. Both studies used an oily extract rather than the vegetable. Boiling costs vitamin C. UK tables drop red pepper from 126 to 89 mg per 3.5 oz (100 g) once boiled in unsalted water, about 30% less, while carotene holds at 617 against 580 ug. The USDA factor for vegetables boiled in water and drained keeps about 75% of vitamin C, a group figure from 1975 that was never measured on pepper. Sweet pepper extract did not act as a fat burner in the one trial we have. Capsiate at 12 mg a day for 10 weeks did not change body fat, appetite or strength in 24 young men doing resistance training. Among 2,451 older adults, eating sweet peppers two to three times a week or more went with about one third lower odds of sarcopenia than almost never (odds ratio 0.66, 95% CI 0.45 to 0.95). That survey was cross-sectional and cannot show which came first. With children, the hard part is getting pepper eaten at all. Preschoolers who watched peers eat bell pepper on video ate 15.5 g of it a week later against 5.9 g in controls, with no difference on the first two days. Offering several vegetables together, pepper among them, raised what 61 preschoolers ate of vegetables and fruit by about 31 g. The cautions we have are thin. A 16 year old with mugwort pollen allergy and lipid transfer protein syndrome had positive skin tests to raw and cooked bell pepper, one of many foods that reacted. In a Korean survey of retail vegetables, 18 of 21 Bacillus cereus isolates from bell peppers carried all eight enterotoxin genes, and the genes alone do not mean anyone fell ill. We found no data on pregnancy, kidney disease or drug interactions.

Sources

1. bpr8-01 · dataset
   Pepper, capsicum, red, raw (CoFID 13-524): Vitamin C 126 mg; Carotene 580 µg; Energy 21 kcal; Total sugars 4.2 g; AOAC fibre 2.2 g per 100 g
   CoFID 2021 (Public Health England), code 13-524 Pepper, capsicum, red, raw · checked 2026-09-29
2. bpr8-02 · dataset
   Peppers, capsicum, green, raw (CoFID 13-318): Vitamin C 120 mg; Carotene 265 µg; Energy 15 kcal; Total sugars 2.4 g per 100 g
   CoFID 2021 (Public Health England), code 13-318 Peppers, capsicum, green, raw · checked 2026-09-29
3. bpr8-05 · dataset
   FNDDS 2709801 Peppers, sweet, red, raw (code 75122200): Vitamin C, total ascorbic acid 141.7 mg/100 g · 1 regular 120 g 170.0 mg · 1 cup 150 g 212.6 mg
   USDA FNDDS (WWEIA 2021-2023), fdc_id 2709801 Peppers, sweet, red, raw · checked 2026-09-29
4. bpr8-12 · RCT
   Serving a variety also increased consumption of both vegetables and fruit (P < 0.0002); the mean (±SEM) increase was 31 ± 5 g, about one-sixth the recommended daily amount. Independent of the variety effect, children were less likely to select vegetables than fruit (P < 0.0001), and the mean intake was substantially less for vegetables than for fruit (22 ± 1 compared with 84 ± 3 g).
   Am J Clin Nutr, 2013 · checked 2026-09-29
5. bpr8-07 · RCT
   In these experiments, β-cryptoxanthin and zeaxanthin dose-dependently accumulated in plasma within the dose range of the study over 12 consecutive weeks of paprika oleoresin supplementation. ... In contrast, capsanthin was not detected in plasma before or during the 12-week treatment period. Finally, no adverse events were associated with intake of paprika oleoresin (20 and 100 mg/day) in safety evaluations.
   J Oleo Sci, 2018 · checked 2026-09-29
6. bpr8-03 · dataset
   Pepper, capsicum, red, boiled in unsalted water (CoFID 13-525): Vitamin C 89 mg; Carotene 617 µg; Energy 17 kcal per 100 g
   CoFID 2021 (Public Health England), code 13-525 Pepper, capsicum, red, boiled in unsalted water · checked 2026-09-29
7. bpr8-04 · dataset
   USDA-RETN-R6:3775 VEG,OTHER,BLD,WATER COVER,DRAINED (Vegetables and Vegetable Products): vitamin_c_mg 75%; folate_total_ug 65%; thiamin_mg 80%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), Retn_Code 3775 · checked 2026-09-29
8. bpr8-15 · prevalence survey
   Of 102 examined samples, 48 (47%) of the samples were contaminated with B. cereus (>1 log CFU/g) and 7 (6.8%) of the samples showed more than 3 log CFU/g. ... Eighteen (80%) of 21 isolates from bell peppers possessed eight enterotoxin genes.
   J Food Prot, 2018 · checked 2026-09-29
9. bpr8-09 · meta-analysis of RCTs
   The results of four eligible RCTs showed that C. annuum supplementation could significantly reduce total cholesterol (TC) (WMD: -4.98 mg/dL, 95% CI: -7.08 to -2.88, p ≤ 0.001) levels, but did not regulate triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol concentrations.
   Phytother Res, 2023 · checked 2026-09-29
10. bpr8-11 · cross-sectional
    After adjustment for potential confounding variables, 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 (both P for trend <0.01), respectively.
    Aging (Albany NY), 2021 · checked 2026-09-29
11. bpr8-14 · case report
    A skin prick test demonstrated positive reactions to a wide variety of both non-heated and heated vegetables and fruits such as wild grape, bell pepper, onion, Chinese cabbage, tomato, eggplant, and broccoli.
    J Dermatol, 2021 · checked 2026-09-29
12. bpr8-08 · meta-analysis of RCTs
    Analysis of the included 11 studies (n = 609) showed that C. annuum supplementation had significant effect on low density lipoprotein-cholesterol [SMD = - 0.39; 95% CI - 0.72, - 0.07; P = 0.02; prediction interval, - 1.28 to 0.50] and marginally significant effect on body weight [SMD = - 0.19; 95% CI - 0.40, 0.03; P = 0.09].
    Sci Rep, 2020 · checked 2026-09-29
13. bpr8-10 · RCT
    In conclusion, 10 weeks of resistance training increased total body weight, muscle mass, and maximum strength in healthy untrained men; however, CAP supplementation (12 mg, 7 days per week) failed to change adipose tissue-derived hormones, appetite, body composition and muscle strength in this population.
    Nutr Res, 2024 · checked 2026-09-29
14. bpr8-13 · RCT
    Children in the vegetable condition ate more bell peppers (15.5 g) than did those in the control condition (5.9 g; P = .04; model η(2) = 0.85) on day 7, with no differences on days 1 or 2.
    J Nutr Educ Behav, 2016 · checked 2026-09-29
15. bpr8-06 · clinical trial
    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 2026-09-29