Marmalade: sugar set with citrus peel

When 10 g of pectin was stirred into the marmalade of a toast breakfast, blood sugar 15 minutes later fell from 111 to 102 mg/dL (6.18 to 5.64 mmol/L) in 8 adults, in a 1977 trial that used far more pectin than marmalade naturally holds. By weight the jar is mostly sugar. UK food tables list 261 calories and 69.5 g of sugars per 3.5 oz (100 g), nearly all of the carbohydrate, with 0.5 g of fiber, from a single entry that varies by recipe and brand. Portions are small. The US survey database counts 10 g on a slice of bread and 14 g in a single-serve packet, which are guideline amounts and were not measured from what people ate. At the UK figure, those 10 g carry about 7 g of sugar. The two national tables disagree on vitamin C, 4.8 mg per 3.5 oz (100 g) in the US data and 10 mg in the UK data, and neither shows the spread across samples.

The numbers, per 3.5 oz (100 g)

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• UK food tables list marmalade at 261 calories and 69.5 g of sugars per 3.5 oz (100 g), almost all of its carbohydrate, with only 0.5 g of fiber. — UK composition data (n = CoFID 2,886 foods) Evidence E source
  Per 100 g: 261 calories, total sugars 69.5 g (glucose 27.6, sucrose 18.8, fructose 15.0, maltose 8.0), AOAC fiber 0.5 g, water 28 g

What a real portion looks like

• In the US survey database a typical marmalade portion is small: 10 g per slice of bread and 14 g in a single-serve packet. — US household measures, FNDDS 2021-2023 (n = FNDDS 5,432 foods) Evidence E source
  10 g per slice of bread or roll; 14 g per individual packet

What your body absorbs

• In a 1977 trial in 8 adults, stirring 10 g of pectin into the marmalade of a toast breakfast lowered the 15-minute blood glucose from 111 to 102 mg/dL (6.18 to 5.64 mmol/L). — Adults eating a bread, butter, marmalade and tea breakfast (n = 8) Evidence B source
  15-min glucose 6.18 +/- 0.21 to 5.64 +/- 3.1 mg/dL (0.17 mmol/L); insulin lower at 15-45 min

What it does to your health

• In an Italian case-control study of 5,157 women, the highest intake of sugars including jam and marmalade went with 19% higher odds of breast cancer. — 2569 cases and 2588 hospital controls, Italy 1991-1994 (n = 5157) Evidence C source
  OR 1.19 (95% CI 1.02-1.38), highest vs lowest tertile

Safety, limits and interactions

• In a randomized study, Seville orange juice, the bitter orange used for marmalade, cut gut CYP3A4 enzyme levels by about 40%, though it did not change cyclosporine levels. — Healthy volunteers; enterocyte CYP3A4 measured in 2 Evidence B source
  Enterocyte CYP3A4 -40%; cyclosporine disposition unchanged
• In a study of 11 volunteers, Seville orange juice raised the absorption of dextromethorphan as grapefruit juice does, with the effect lasting days. — Healthy volunteers, 6.8 fl oz (200 ml) juice with 30 mg dextromethorphan (n = 11) Evidence C source
  Bioavailability increased; only half back to baseline after 3-day washout
• In phase I studies, Seville orange juice taken twice daily for 4 days lowered colchicine peak level by about 24% instead of raising it. — Healthy volunteers, 8.1 fl oz (240 mL) juice twice daily (n = 44) Evidence C source
  Cmax -24%, AUC -20%, Tmax delayed about 1 h
• Danish monitoring found most marmalades contain benzoic or sorbic acid preservatives, and high-consuming 4-6-year-olds can exceed the benzoic acid ADI. — Danish food samples 2001-2006 and 5,785 survey participants aged 4-75 (n = 1526 samples) Evidence C source
  90th percentile benzoic acid up to 16 mg/kg bw/day in 4-6-year-olds vs ADI 0-5

What people believe that the data does not support

• In a crossover RCT of 16 adults, 2.1 oz (60 g) of high-sugar jam raised blood glucose and insulin at 30 and 60 minutes more than low-sugar versions. — Healthy adults, single 2.1 oz (60 g) servings of strawberry jam (n = 16) Evidence B source
  Higher glucose and insulin at 30 and 60 min with high-sugar jam; added antioxidant gave no extra benefit
• EU law reserves the name marmalade for citrus products: at least 7.1 oz (200 g) of citrus per 1,000 g, of which at least 75 g from the fruit segments. — Products sold as marmalade under Directive 2001/113 Evidence E source
  Minimum 200 g citrus per kg, 75 g from endocarp

Who this works differently for

• In a Swedish cohort of 27,786 adults followed 25 years, eating more than 10 servings of jam or marmalade a week went with 14% lower dementia risk. — Adults aged 45-74 at baseline, Malmo Diet and Cancer Study, median 25 years (n = 27786) Evidence C source
  HR 0.86 (95% CI 0.77-0.97), >10 vs <0.5 servings/week
• In a 2-year RCT in 4-year-olds, swapping sucrose for invert sugar in sweet foods including marmalade did not significantly change new caries (3.86 vs 3.10 surfaces). — Preschool children in Malmo, 2 years; 114 of 187 completed (n = 114) Evidence B source
  Dmfs increment 3.86 (sucrose) vs 3.10 (invert sugar), p = 0.34
• In 7 adults with type 2 diabetes, prune marmalade made with 10% lupin flour gave lower blood glucose after the meal than fructose-sweetened marmalade. — Adults with non-insulin-dependent diabetes, glucose tolerance test (n = 7) Evidence C source
  Lower postprandial glucose; size not reported in abstract

What is still unknown

• Two national food tables disagree on marmalade's vitamin C: 4.8 mg per 3.5 oz (100 g) in the US data against 10 mg in the UK data. — US and UK composition data (n = 2 records) Evidence E source
  Vitamin C 4.8 (USDA) vs 10 mg/100 g (CoFID); copper 0.09 vs 0.03 mg

The bottom line

In 16 healthy adults, 2.1 oz (60 g) of high-sugar strawberry jam raised blood glucose and insulin at 30 and 60 minutes more than low-sugar versions. That trial used jam made from strawberries. A 2-year trial in 4-year-olds in Malmo swapped sucrose for invert sugar in sweet products including marmalade, and new caries did not differ significantly (3.86 against 3.10 surfaces, p = 0.34), with 39 percent of the children dropping out. In 7 adults with type 2 diabetes, a prune marmalade made with 10 percent lupin flour gave lower blood glucose after the meal than a fructose-sweetened one, and the abstract gives no size. Two observational studies point in opposite directions, and neither isolates marmalade. In a Swedish cohort of 27,786 adults followed for a median of 25 years, eating more than 10 servings of jam or marmalade a week went with a 14 percent lower risk of dementia (HR 0.86, 95% CI 0.77 to 0.97) against under half a serving. That is an association, open to residual confounding. An Italian case-control study of 5,157 women linked the top third of intake of a sugars group, which pooled sugar, honey, jam, marmalade and chocolate, with 19 percent higher odds of breast cancer (OR 1.19, 95% CI 1.02 to 1.38). Case-control designs are prone to recall bias. Under EU rules as kept in UK law, a product sold as marmalade needs at least 7.1 oz (200 g) of citrus per 1,000 g, at least 2.6 oz (75 g) of it from the fruit segments. An EU amendment applying from June 2026 renames it citrus marmalade, and we have not checked its threshold word for word. Who should be careful. Seville orange, the bitter orange used for marmalade, interacts with some drugs when taken as juice. In a randomized study it cut the gut enzyme CYP3A4 by about 40 percent, measured in 2 volunteers, without changing cyclosporine levels. In 11 volunteers it raised the absorption of dextromethorphan, and the effect was only half gone after 3 days. With colchicine it lowered the peak level by about 24 percent. All three studies used juice, and we found no measurement of what survives in cooked peel. Danish monitoring found benzoic and sorbic acid preservatives in most marmalades, though soft drinks and dressings supply most of the benzoic acid people take in. In that survey, the 90th percentile of benzoic acid intake in children aged 4 to 6 reached up to 16 mg per kg of body weight a day, above the acceptable daily intake of 0 to 5 mg. We found nothing on marmalade in pregnancy.

Compared with other foods

Sources

1. mrm-r7-01 · reference dataset
   CoFID 17-078 Marmalade: Energy 261 kcal/100 g · Carbohydrate 69.5 g · Total sugars 69.5 g (Glucose 27.6, Sucrose 18.8, Fructose 15.0, Maltose 8.0) · AOAC fibre 0.5 g · Water 28.0 g
   CoFID 2021, Public Health England / OGL v3.0 · checked 2026-10-02
2. mrm-r7-03 · reference dataset
   FNDDS Marmalade (fdc 2710303): Guideline amount per slice of bread/roll 10 g · 1 individual packet 14 g
   USDA FNDDS 2021-2023 (FoodData Central) · checked 2026-10-02
3. mrm-r7-04 · RCT
   A breakfast test meal (bread, butter, marmalade, and tea) resulted in a mean 15-min blood glucose of 6.18 +/- 0.21 mmol/litre (111 +/- 4 mg/dl) in eight subjects; 10 g of pectin added to the marmalade reduced this level to 5.64 +/- 0.17 mmol/litre (102 +/- 3 mg/dl) (P less than 0.01).
   Ann Intern Med, 1977 · checked 2026-10-02
4. mrm-r7-10 · Case-control
   Compared with women with the lowest tertile of intake, women in the highest tertile of intake of desserts (including biscuits, brioches, cakes, puffs and ice-cream) and sugars (including sugar, honey, jam, marmalade and chocolate) had multivariate ORs of 1.19 (95% CI 1.02-1.39) and 1.19 (95% CI 1.02-1.38), respectively.
   Ann Oncol, 2006 · checked 2026-10-02
5. mrm-r7-06 · RCT
   Seville orange juice had no influence on cyclosporine disposition but reduced enterocyte concentrations of CYP3A4 by an average of 40%.
   Clin Pharmacol Ther, 1999 · checked 2026-10-02
6. mrm-r7-07 · Clinical trial
   Bioavailability (F) of DM increased significantly with grapefruit and seville orange juice, but only returned to half the baseline value after three days of washout.
   Life Sci, 2002 · checked 2026-10-02
7. mrm-r7-08 · Clinical trial
   When colchicine was administered with Seville orange juice, a moderate inhibitor, C(max) and AUC were decreased by ∼24% and ∼20%, respectively.
   Clin Ther, 2012 · checked 2026-10-02
8. mrm-r7-12 · Exposure survey
   Most foods in the categories soft drinks, dressings, fat-based salads, pickled herrings, and marmalade contain benzoic and sorbic acid, and sliced bread also contains in some cases sorbic acid.
   Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2010 · checked 2026-10-02
9. mrm-r7-05 · RCT
   However, blood glucose and insulin were significantly higher at 30 and 60 min after high-sugar (HS) jam intake versus both low-sugar jams.
   Eur J Nutr, 2014 · checked 2026-10-02
10. mrm-r7-14 · Legislation
    The quantity of citrus fruit used in the manufacture of 1 000 g of finished product must not be less than 200 g of which at least 75 g must be obtained from the endocarp.
    Council Directive 2001/113/EC, Annex I (legislation.gov.uk) · checked 2026-10-02
11. mrm-r7-09 · Cohort
    High chocolate intake was associated with lower risks of all-cause [HR for quintile 5 (Q5) compared with Q1: 0.81; 95% CI: 0.72, 0.91] and vascular dementia (HR for Q5 compared with Q1: 0.68; 95% CI: 0.50, 0.92), whereas high jam/marmalade intake was linked to a lower risk of all-cause dementia (HR: 0.86; 95% CI: 0.77, 0.97 for >10 servings per week compared with <0.5 servings per week).
    J Nutr, 2026 · checked 2026-10-02
12. mrm-r7-11 · RCT
    The mean caries increment, including initial lesions, was 3.86 dmfs in the combined groups S and SD (n = 63) and 3.10 dmfs in the combined groups I and ID (n = 51) during the 2 years (p = 0.34).
    Caries Res, 1991 · checked 2026-10-02
13. mrm-r7-13 · Controlled trial
    Postprandial blood glucose concentration data was lower in individuals after a test meal of lupin marmalade compared to fructose marmalade.
    Arch Latinoam Nutr, 1996 · checked 2026-10-02
14. mrm-r7-02 · reference dataset
    USDA SR Legacy FDC 168819 Marmalade, orange: Vitamin C 4.8 mg/100 g, Copper 0.09 mg/100 g, Carbohydrate 66.3 g/100 g | CoFID 17-078 Marmalade: Vitamin C 10 mg/100 g, Copper 0.03 mg/100 g, Carbohydrate 69.5 g/100 g
    USDA SR Legacy 2018 (FDC 168819); CoFID 2021 · checked 2026-10-02