Orange and pepper: juice trials on one side, more vitamin C on the other

A meta-analysis of 10 randomized trials of orange juice found it lowered LDL cholesterol by 9.14 mg/dl (95% CI 2.49 to 15.79) and fasting glucose by 2.92 mg/dl against control, with the effects holding at 17 fl oz (500 mL) a day or more. Those trials used juice, and the whole fruit was not tested. Red pepper has nothing comparable. It was tested as capsaicin or red pepper supplements, and a 2026 meta-analysis of 13 trials in 821 adults found results so mixed, and a total sample so small, that its authors ask for cautious reading, with certainty rated low to very low. On vitamin C the ranking flips. Raw red bell pepper averaged 141.7 mg per 3.5 oz (100 g) across 9 USDA samples, against 59.1 mg in 8 samples of navel orange, and the UK table shows a similar gap (126 against 52 mg). Pepper on this page means capsicum, sweet or hot. Black pepper is a different plant and is left out.

How much is actually in it

• Raw navel oranges averaged 59.1 mg vitamin C per 3.5 oz (100 g) in USDA Foundation Foods, ranging 51.8 to 65.6 mg across 8 samples. — Oranges, raw, navels; 8 analytical samples (n = 8) Evidence E source
  Mean 59.1 mg/100 g, range 51.8-65.6 (spread 23%)
• Raw red bell peppers averaged 141.7 mg vitamin C per 3.5 oz (100 g) in USDA Foundation Foods (range 116 to 220.5 mg, 9 samples), green bell peppers 99.5 mg. — Peppers, bell, red, raw (9 samples); Peppers, bell, green, raw (8 samples) (n = 17) Evidence E source
  Red mean 141.7 mg/100 g (116.0-220.5); green mean 99.5 mg/100 g (70.35-138.0)
• The UK CoFID 2021 lists 52 mg vitamin C per 3.5 oz (100 g) for orange flesh and 126 mg for raw red capsicum pepper, a second independent figure close to the USDA means. — CoFID 14-327 Oranges, flesh only; CoFID 13-524 Pepper, capsicum, red, raw (n = -) Evidence E source
  Orange 52 mg/100 g vs red pepper 126 mg/100 g
• In CoFID 2021 raw red capsicum pepper carries 580 micrograms carotene and 216 mg potassium per 3.5 oz (100 g), against 55 micrograms and 122 mg for orange flesh. — CoFID 14-327 Oranges, flesh only; CoFID 13-524 Pepper, capsicum, red, raw (n = -) Evidence E source
  Carotene 580 vs 55 ug/100 g; potassium 216 vs 122 mg/100 g; energy 21 vs 36 calories
• Laboratory analysis in a 2025 Korean trial measured 56.45 mg vitamin C per 3.5 oz (100 g) in orange bell pepper but only 8.01 mg in mandarin orange. — market samples of mandarin orange, cherry tomato and orange bell pepper bought in Korea, April 2023 (n = -) Evidence D source
  Orange bell pepper 56.45 +/- 2.48 vs mandarin 8.01 +/- 0.38 mg/100 g (ascorbic acid only)
• The NIH Office of Dietary Supplements names citrus fruits and red and green peppers among the best food sources of vitamin C. — general population, US (n = -) Evidence E source
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What a real portion looks like

• In the US dietary survey database one raw orange weighs 5.4 oz (154 g) and one regular raw pepper 120 g, which at USDA Foundation means gives about 91 mg and 170 mg of vitamin C. — FNDDS 61119010 Orange, raw (1 fruit 154 g, 1 cup 180 g); FNDDS 75122000 Peppers, raw, NFS (1 regular 120 g, 1 cup 150 g) (n = -) Evidence E source
  Portion weights 154 g vs 120 g; derived vitamin C 154 x 0.591 = 91 mg, 120 x 1.417 = 170 mg (red bell mean)

What your body absorbs

• In a randomized crossover trial in 12 adults, 101.7 mg vitamin C as mandarin, tomato and orange bell pepper juice gave a plasma AUC of 23.5 mg/dL·h versus 16.1 for the same raw produce and 11.9 for powder. — 12 healthy non-smoking adults, three 1-day crossover sessions, 2-week washout (n = 12) Evidence B source
  Plasma vitamin C AUC 23.5 +/- 3.2 (juice) vs 16.1 +/- 2.0 (raw) vs 11.9 +/- 2.1 mg/dL·h (powder)
• In a randomized crossover study in 20 people, flavanones from 150 g orange fruit and 300 g orange juice were absorbed and excreted equally once adjusted for dose. — 20 subjects, single portion of orange fruit (150 g) or juice (300 g) (n = 20) Evidence B source
  No difference in dose-adjusted absorption or excretion of hesperetin or naringenin between fruit and juice
• Among 109 people aged 18 to 80 drinking orange juice, urinary yield of flavanones ranged from 0 to 59 percent, and hesperetin excretion fell slightly with age. — 109 subjects aged 18-80 years consuming orange juice (n = 109) Evidence C source
  Urinary yield range 0-59%; small significant decrease of hesperetin excretion with age (P < 0.05)
• In a 3-period crossover RCT in 37 centrally overweight men, 11 fl oz (330 mL) orange juice daily for 6 weeks delivered hesperidin as well as a 210 mg supplement but did not change flow-mediated dilation. — 37 centrally overweight men, three 6-week interventions (n = 37) Evidence B source
  Comparable phase II hesperetin AUC0-6h and 24 h urinary excretion (juice vs supplement); no significant FMD change vs control

What cooking and storage change

• By the USDA retention table for Fruits and Fruit Juices, cooked citrus keeps 95 percent of vitamin C while canned fruit keeps 50 percent and dried fruit 20 percent. — USDA R6 group factors, Fruits and Fruit Juices (codes 270, 154, 158) (n = -) Evidence E source
  Vitamin C retention: citrus cooked 95%, canned 50%, dried 20%
• By the USDA retention table for Vegetables and Vegetable Products, boiling in covering water and draining keeps 75 percent of vitamin C, while baking or frying keeps 85 percent. — USDA R6 group factors, Vegetables and Vegetable Products, other vegetables (codes 3775, 3771, 3780) (n = -) Evidence E source
  Vitamin C retention: boiled water cover drained 75%, baked 85%, fried 85%
• The NIH Office of Dietary Supplements states that heat and prolonged storage reduce vitamin C in food and that steaming or microwaving may lessen losses. — general population, US (n = -) Evidence E source
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What it does to your health

• A meta-analysis of 10 RCTs found orange juice lowered LDL cholesterol by 9.14 mg/dl and fasting glucose by 2.92 mg/dl versus control. — adults in 10 randomized controlled trials (n = 10 RCTs) Evidence A source
  LDL-C WMD -9.14 mg/dl (95% CI -15.79 to -2.49); glucose WMD -2.92 mg/dl (-5.327 to -0.530); total cholesterol -9.84 mg/dl
• A synthesis of 24 randomized studies found capsaicin lowered respiratory quotient during negative energy balance and in high-protein conditions, a sign of more fat oxidation. — humans in 24 randomized controlled studies (22 publications), 1-meal, 24-hour and long-term designs (n = 24 studies) Evidence A source
  RQ significantly reduced in negative energy balance and high-protein conditions; EE change not significant overall
• A meta-analysis of 3 RCTs with 252 overweight adults found a Moro orange juice extract supplement reduced body weight by 4.6 lb (2.08 kg) versus placebo. — 252 overweight and obese adults in 3 RCTs, Moro orange juice extract vs placebo (n = 252) Evidence A source
  Body weight MD -4.6 lb (95% CI -7.7 to -1.5; metric: -2.08 kg, -3.50 to -0.67); fat mass MD -3.4 lb (-6.4 to -0.33; metric: -1.53 kg, -2.92 to -0.15)

Safety, limits and interactions

• A 2026 case report describes serum potassium of 9.4 mmol/L in a 40-year-old man with normal kidneys after weeks of drinking large volumes of reconstituted dried orange juice powder. — one 40-year-old man with normal renal function (n = 1) Evidence D source
  Serum potassium up to 9.4 mmol/L, ICU admission; resolved after stopping the drink
• A 2026 case series of 2 elderly patients found inhaled chili pepper fragments obstructing distal airways and mimicking pneumonia or tumor until bronchoscopy. — 2 elderly patients with subacute respiratory symptoms (n = 2) Evidence D source
  Fragments removed by cryoextraction; residual bronchiectasis
• A 2025 meta-analysis of 51 pharmacokinetic studies found fruit juices can raise or lower blood levels of antihypertensive drugs, with orange and apple juice acting on some drugs like grapefruit juice. — 51 human pharmacokinetic studies, mostly open-label crossover trials (n = 51 studies) Evidence A source
  Grapefruit juice cut aliskiren and celiprolol AUC and Cmax by about 80-90%; orange juice comparable on certain drugs

What people believe that the data does not support

• The EU did not authorize the claim that orange supports good circulation of blood in microvessels or relieves heavy legs. — EU market (n = -) Evidence E source
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• The EU did not authorize the claim that cryptoxanthin from orange juice strengthens the immune system or has antioxidant action. — EU market (n = -) Evidence E source
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Who this works differently for

• A meta-analysis of 8 trials in 530 people found capsinoids and red pepper did not lower glucose overall (WMD -0.27 mg/dL) but did lower glucose in people older than 40. — 530 subjects in 8 randomized trials (9 effect sizes) (n = 530) Evidence A source
  Glucose WMD -0.27 mg/dL (95% CI -1.9 to 1.37); HbA1c WMD 0.01%; subgroup >40 years reduced glucose
• In an observational study of 582 hemodialysis patients in Portugal, eating bell peppers was among the foods that predicted greater overhydration. — 582 hemodialysis patients from 37 Portuguese centers (n = 582) Evidence C source
  Bell pepper intake predicted greater hyperhydration (with bacon, snacks, carrots, cherries, soup)

What is still unknown

• A 2026 meta-analysis of 13 RCTs with 821 adults found red pepper or capsaicin supplements gave only small, unstable drops in total cholesterol and diastolic pressure, with low to very low certainty. — adults in 13 RCTs supplementing capsaicin, red pepper or related compounds vs placebo (n = 821) Evidence A source
  No significant effect on TG, LDL, HDL, SBP, glucose, insulin, HOMA-IR, HbA1c; TC and DBP reductions lost after sensitivity analysis

The bottom line

Per portion the gap holds. The US survey database weighs one raw orange at 154 g and one regular pepper at 120 g, which at the USDA means comes to about 91 mg and 170 mg of vitamin C, a calculation from 100 g values that uses the red bell pepper figure. Red pepper also carries far more carotene than orange flesh in the UK table, 580 against 55 ug per 3.5 oz (100 g). Heat costs vitamin C in both. The USDA retention table keeps 95 percent in cooked citrus, and for vegetables in general 75 percent after boiling and draining and 85 percent after baking or frying. Those are group factors, not measured on these two foods. In 12 adults over one-day sessions, a juice of mandarin, cherry tomato and orange bell pepper gave a larger plasma vitamin C curve than the same raw produce (23.5 against 16.1 mg/dL h). Orange flavanones were absorbed alike from 5.3 oz (150 g) of fruit and 11 oz (300 g) of juice in 20 people, once adjusted for dose. The weight-loss stories are about extracts. Three trials in 252 overweight adults found a Moro orange juice extract supplement cut body weight by 4.6 lb (2.08 kg) against placebo. Across 24 randomized studies, capsaicin lowered the respiratory quotient during negative energy balance, which the authors read as more fat oxidation. Neither tells you much about eating an orange or a pepper. The EU did not authorize claims that orange helps circulation in small blood vessels or that cryptoxanthin from orange juice strengthens the immune system. Non-authorized means the evidence was not accepted, and it does not mean the effect was ruled out. Cautions. A 2025 meta-analysis of 51 pharmacokinetic studies found that fruit juices can change blood levels of some blood pressure drugs, with orange and apple juice acting alike on certain medications. If you take one, ask about juice. A 40-year-old man with healthy kidneys reached a serum potassium of 9.4 mmol/L after weeks of drinking large volumes of reconstituted orange juice powder, a single case. Two elderly patients inhaled chili pepper fragments that blocked their airways and looked like pneumonia or a tumor until bronchoscopy. Among 582 hemodialysis patients in Portugal, eating bell peppers was among the foods that predicted more fluid overload, an association. We found no study of either food in pregnancy or in children.

Sources

1. orpp-daily-r7-01 · composition dataset
   Oranges, raw, navels (USDA FoodData Central, Foundation Foods, release 2026-04-30): Vitamin C, total ascorbic acid 59.1 MG, range 51.8-65.6 (median 58.0), samples 8, spread 23%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 (Oranges, raw, navels) · checked 2026-09-29
2. orpp-daily-r7-02 · composition dataset
   Peppers, bell, red, raw (USDA FoodData Central, Foundation Foods, release 2026-04-30): Vitamin C, total ascorbic acid 141.7 MG, range 116.0-220.5 (median 130.0), samples 9, spread 74%; Peppers, bell, green, raw: 99.51 MG, range 70.35-138.0 (median 96.23), samples 8, spread 68%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 (Peppers, bell, red/green, raw) · checked 2026-09-29
3. orpp-daily-r7-03 · composition dataset
   CoFID 2021 14-327 Oranges, flesh only: Vitamin C (mg) 52; CoFID 2021 13-524 Pepper, capsicum, red, raw: Vitamin C (mg) 126
   CoFID 2021, Public Health England, codes 14-327 and 13-524 (OGL v3.0) · checked 2026-09-29
4. orpp-daily-r7-04 · composition dataset
   CoFID 2021 14-327 Oranges, flesh only: Carotene (ug) 55, Potassium (mg) 122, Energy (kcal) 36; CoFID 2021 13-524 Pepper, capsicum, red, raw: Carotene (ug) 580, Potassium (mg) 216, Energy (kcal) 21
   CoFID 2021, Public Health England, codes 14-327 and 13-524 (OGL v3.0) · checked 2026-09-29
5. orpp-daily-r7-06 · lab analysis
   The measured vitamin C content was 8.01 ± 0.38 mg/100 g for mandarin orange, 14.31 ± 1.21 mg/100 g for cherry tomato, 56.45 ± 2.48 mg/100 g for orange bell pepper, and 50.21 ± 8.90 mg/100 g for the mixed juice.
   Nutrients, 2025 · checked 2026-09-29
6. orpp-daily-r7-13 · agency fact sheet
   The best sources of vitamin C are fruits and vegetables, especially citrus fruits, red and green peppers, kiwifruit, broccoli, strawberries, and Brussels sprouts.
   NIH Office of Dietary Supplements, Vitamin C Health Professional Fact Sheet · checked 2026-09-29
7. orpp-daily-r7-12 · portion dataset
   FNDDS 61119010 Orange, raw (fdc_id 2709171, Citrus fruits): 1 fruit 154 g, 1 cup 180 g; FNDDS 75122000 Peppers, raw, NFS (fdc_id 2709799, Other vegetables and combinations): 1 regular 120 g, 1 cup 150 g
   USDA FNDDS 2021-2023, food codes 61119010 and 75122000 · checked 2026-09-29
8. orpp-daily-r7-05 · RCT (crossover)
   The area under the curve (AUC) for plasma vitamin C concentrations further confirmed this trend, with the C group showing the highest value (23.5± 3.2 mg/dL·h), followed by the A group (11.9 ± 2.1 mg/dL·h) and B group (16.1 ± 2.0 mg/dL·h) (Figure 2B).
   Nutrients, 2025 · checked 2026-09-29
9. orpp-daily-r7-07 · RCT (crossover)
   Analysis of the plasma pharmacokinetic and urinary excretion data on a dose-adjusted basis indicated no difference in absorption or excretion of either flavanone between the fruit and juice matrices.
   Br J Nutr, 2009 · checked 2026-09-29
10. orpp-daily-r7-08 · uncontrolled extension
    In the extended urinary excretion dataset the individual variation was very large (range 0-59 % urinary yield). There was a small but significant (P < 0.05) decrease in the excretion of hesperetin (but not naringenin) with increasing age (P < 0.05)
    Br J Nutr, 2009 · checked 2026-09-29
11. orpp-daily-r7-09 · RCT (crossover)
    Plasma exposure to phase II hesperetin metabolites (AUC0-6 h) and 24 h urinary excretion were comparable after OJ and HESP, indicating effective hesperidin delivery and limited matrix effects on bioavailability. Neither intervention significantly affected fasting or postprandial FMD, vascular, metabolic or anthropometric parameters, or oxylipin profiles versus CON.
    Food Funct, 2026 · checked 2026-09-29
12. orpp-daily-r7-10 · retention dataset
    USDA-RETN-R6:270 FRUITS,CITRUS,CKD, group Fruits and Fruit Juices: vitamin_c_mg 95% retained; USDA-RETN-R6:154 FRUITS,CANNED: vitamin_c_mg 50% retained; USDA-RETN-R6:158 FRUITS,DRIED: vitamin_c_mg 20% retained
    USDA Table of Nutrient Retention Factors, Release 6 (2007), codes 270, 154, 158 · checked 2026-09-29
13. orpp-daily-r7-11 · retention dataset
    USDA-RETN-R6:3775 VEG,OTHER,BLD,WATER COVER,DRAINED, group Vegetables and Vegetable Products: vitamin_c_mg 75% retained; USDA-RETN-R6:3771 VEG,OTHER,BAKED: vitamin_c_mg 85% retained; USDA-RETN-R6:3780 VEG,OTHER,FRIED: vitamin_c_mg 85% retained
    USDA Table of Nutrient Retention Factors, Release 6 (2007), codes 3775, 3771, 3780 · checked 2026-09-29
14. orpp-daily-r7-14 · agency fact sheet
    The vitamin C content of food may be reduced by prolonged storage and by cooking because ascorbic acid is water soluble and is destroyed by heat [6,8]. Steaming or microwaving may lessen cooking losses.
    NIH Office of Dietary Supplements, Vitamin C Health Professional Fact Sheet · checked 2026-09-29
15. orpp-daily-r7-15 · meta-analysis
    Pooled results demonstrated a significant effect of orange juice on glucose (WMD: -2.92 mg/dl, 95% CI: -5.327, -0.530, p = 0.017), insulin (WMD: -1.229 μU/ml, 95% CI: -2.083, -0.374, p = 0.005), HOMA-IR (WMD: -0.464, 95% CI: -0.747, -0.181, p = 0.001), total cholesterol (WMD: -9.84 mg/dl, 95% CI: -15.43, -4.24, p = 0.001), LDL-C (WMD: -9.14 mg/dl, 95% CI: -15.79, -2.49, p = 0.007), and CRP (WMD: -0.467 mg/l, 95% CI: -0.815, -0.120, p = 0.008) compared to control group.
    Crit Rev Food Sci Nutr, 2022 · checked 2026-09-29
16. orpp-daily-r7-18 · meta-analysis
    Capsaicin significantly reduced RQ in negative-EB and in high-protein conditions, indicating greater fat oxidation.
    Nutr Rev, 2026 · checked 2026-09-29
17. orpp-daily-r7-19 · meta-analysis
    The extract significantly reduced body weight (mean difference (MD) -2.08 kg; 95% confidence interval (CI) -3.50, -0.67; I2 = 0%; p < 0.01) and fat mass (MD -1.53 kg; 95% CI -2.92, -0.15; I2 = 0%; p = 0.03)
    Nutr Health, 2026 · checked 2026-09-29
18. orpp-daily-r7-20 · case report
    Further history revealed excessive daily consumption of large volumes of a dried orange juice powder reconstituted as a beverage over several weeks.
    Cureus, 2026 · checked 2026-09-29
19. orpp-daily-r7-21 · case series
    Flexible bronchoscopy identified chili pepper fragments obstructing the distal airways.
    Front Med (Lausanne), 2026 · checked 2026-09-29
20. orpp-daily-r7-22 · meta-analysis
    Apple and orange juices have comparable effects on certain medications.
    Complement Ther Med, 2025 · checked 2026-09-29
21. orpp-daily-r7-24 · EU claim register
    POL-HC-6941 Citrus sinensis - common name : Orange Traditionally used for the good circulation of blood in microvessels / "Traditionally used to decrease the sensations of heavy leggs" / "Used for the good circulation of blood in microvessels" / "Helps to decrease the sensations of heavy leggs" Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6941, snapshot 2026-09-21 · checked 2026-09-29
22. orpp-daily-r7-25 · EU claim register
    POL-HC-7000 Cryptoxanthin from orange juice (Cryptoxanthin from) orange juice participate to strengthen immune system. Clarification provided (Cryptoxanthin from) orange juice ensure antioxidant action / ensure protective effect on the organism. Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-7000, snapshot 2026-09-21 · checked 2026-09-29
23. orpp-daily-r7-17 · meta-analysis
    Capsinoids and red pepper resulted in no significant reduction in glucose (Weighted mean differences (WMD): -0.27 mg/dL; 95% CI: -1.9 to 1.37, P = .75)
    Int J Clin Pract, 2021 · checked 2026-09-29
24. orpp-daily-r7-23 · observational
    Consumption of bacon, savory snacks, carrots, bell peppers, cherries, and soup predicted greater hyperhydration, while rice, cookies, and grapes show the opposite effect, regardless of age, sex, diabetes, and HD duration.
    Clin Nutr ESPEN, 2026 · checked 2026-09-29
25. orpp-daily-r7-16 · meta-analysis
    Thirteen RCTs (n = 821 participants) were included. However, the findings were marked by substantial heterogeneity and a limited total sample size, which necessitate cautious interpretation.
    Nutr Metab Cardiovasc Dis, 2026 · checked 2026-09-29