Peanut butter and jelly: a sandwich studied mostly through its peanuts

Giving peanut to infants before 12 months cut the risk of peanut allergy by about 69 percent across 3 randomized trials in 4,183 children, RR 0.31 (95% CI 0.17 to 0.54), evidence its authors rated as high to moderate certainty. That finding is about peanut in babies, and the sandwich was never tested. A second review, limited to 8 randomized trials, found no conclusive link between early peanut and peanut allergy. Its peanut part was a narrative summary without a pooled number, which means too few trials to tell. We have no card on the form in which babies were given peanut in these trials or on infants already at high risk of allergy, so this is not a guide to feeding a baby peanut at home. The sandwich itself is known from tables. A 112 g sandwich from a standard recipe gives about 404 calories, 13 g protein, 19 g fat, 51 g carbohydrate, 3 g fiber and 412 mg sodium in the US survey database. The same database puts 16 g of filling on each slice of bread, about a tablespoon, and does not say how it splits between peanut butter and jelly.

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

How much is actually in it

• A peanut butter and jelly sandwich of 112 g gives about 404 calories, 13 g protein, 19 g fat, 51 g carbohydrate, 3 g fiber and 412 mg sodium in the US survey database. — Peanut butter and jelly sandwich, NFS (USDA FNDDS 42302010, fdc_id 2707554) Evidence E source
  Per 100 g: 361 calories, protein 11.42 g, fat 16.6 g, carbohydrate 45.22 g, fiber 2.8 g, sodium 368 mg; per 112 g sandwich about 404 calories

What a real portion looks like

• The US survey database counts a whole peanut butter and jelly sandwich as 112 g and a one-slice half as 56 g, with 16 g of filling (about a tablespoon) per slice of bread. — Peanut butter and jelly sandwich, NFS (FNDDS 42302010) and Peanut butter and jelly filling (fdc_id 2707543) Evidence E source
  1 sandwich 112 g; 1 sandwich (1 slice bread) 56 g; filling 16 g per slice or per tablespoon

What your body absorbs

• In 15 obese women, adding 1.5 oz (42.5 g) of peanut butter to a 75 g carbohydrate breakfast lowered blood glucose after the next meal and reduced the desire to eat. — 15 obese women at high type 2 diabetes risk, breakfast with 42.5 g whole peanuts, peanut butter or none (n = 15) Evidence B source
  Lower second-meal glucose IAUC (240-490 min) and lower desire to eat with peanut butter vs control; whole peanuts similar but not significant
• Adding nuts, peanuts among them, to a bread meal cut iron absorption from 6.6% to 1.8% in 137 women in a 1988 radioisotope trial, and 50 mg of vitamin C canceled the effect. — 137 Indian women fed bread meals with and without walnuts, almonds, peanuts, hazelnuts or coconut (n = 137) Evidence B source
  Geometric mean iron absorption 1.8% from nut meals against 6.6% from bread alone (t = 9.8, p < 0.0005); coconut did not reduce absorption; 50 mg ascorbic acid overcame the inhibition for peanuts and Brazil nuts

What cooking and storage change

• The energy a body actually gets from nuts is lower than the label says, because part of the fat stays locked in cell walls, and grinding or roasting releases more of it than eating them whole. — 21 human and in vitro studies of metabolizable energy and lipid release from tree nuts and peanuts (n = 21 studies) Evidence C source
  Metabolizable energy consistently below Atwater predictions; 22.6 kJ/g for pistachios and 18.5 kJ/g for raw almonds; rises with processing in the order whole nuts, chopped, flour, and raw, roasted, butter
• Roasting cut aflatoxin B1 in nuts by 46.91% across 19 pooled laboratory processing experiments, most of them done on peanuts, and irradiation cut it by 58.60%. That is a share of what was in the batch, not a level made safe. — 19 interventional studies of roasting, irradiation and fumigation of nuts, mostly peanuts (n = 19 trials) Evidence D source
  Roasting reduced aflatoxin B1, B2, G1 and G2 by 46.91%, 30.66%, 40.88% and 26.19%; fumigation reduced B1 by 20.88% and total aflatoxin by 22.56%; irradiation reduced B1 by 58.60% and total by 74.97%

What it does to your health

• In a randomized crossover study in healthy men, a 265 calories snack meal of peanut butter sandwich with chocolate milk gave glucose and insulin responses similar to those of single snacks. — Healthy nondiabetic men, 25 g carbohydrate snacks or 265 calories snack meals Evidence B source
  Glucose and insulin responses similar across isocaloric snack meals; n not in abstract
• When 15 healthy adults in Hong Kong were tested against glucose, jam and peanut butter toast came out as a high glycemic index food. — 15 healthy adults (8 men, 7 women), Hong Kong, 23 test foods after an overnight fast (n = 15) Evidence B source
  Jam and peanut butter toast classed high GI (value not given in abstract)

Safety, limits and interactions

• Giving peanut to infants before 12 months cut the risk of peanut allergy by about 69% (relative risk 0.31, 95% CI 0.17 to 0.54) across 3 randomized trials and 4,183 children. — infants introduced to allergenic foods before 12 months of age, in 12 randomized controlled trials (n = 12 RCTs overall; 3 RCTs and 4,183 participants for the peanut estimate) Evidence A source
  Peanut allergy RR 0.31 (95% CI 0.17 to 0.54); multiple food allergies RR 0.49 (0.33 to 0.74); egg RR 0.58 (0.44 to 0.78); eczema RR 0.88 (0.78 to 1.00)
• Among 60 toddlers living in homes with lead paint and dust, eating peanut butter and jelly sandwiches was associated with higher blood lead in those aged 25 to 36 months. — 60 children aged 13-36 months in homes with lead paint and dust, Jersey City (n = 60) Evidence C source
  Association with higher blood lead in both 13-24 and 25-36 month groups; size not given in abstract

What people believe that the data does not support

• Europe refused the exact sentence a peanut butter jar would want to carry: two tablespoons a day for healthy cholesterol. — — Evidence E source
  Status Non-authorized; all three register entries mentioning peanuts are non-authorized, including the 30 g a day wording for nuts generally

Who this works differently for

• In a study of 792 seven-year-old twins, how much peanut butter and jelly boys ate each day was 79 percent heritable, the highest of any food category. — 792 children aged 7 (396 boys, 396 girls), MacArthur Longitudinal Twin Study, 24-h parental recall (n = 792) Evidence C source
  Heritability of daily peanut butter and jelly intake 79% in boys; not significant in girls

What is still unknown

• A review of 8 randomized trials in infants found no conclusive link between early peanut introduction and peanut allergy, while early egg reduced egg allergy. — 8 randomized controlled trials in infants (n = 8 trials) Evidence A source
  Introducing eggs before 6 months reduced egg allergy (RR 0.60; 95% CI 0.46-0.79), and more strongly in infants with a prior or family history of allergic disease (RR 0.55; 0.40-0.75); the narrative synthesis found no conclusive relationship between early peanut introduction and peanut allergy, and none for cow's milk protein
• A young man eating mostly strawberries and peanut butter sandwiches, with no dairy or seafood, developed goitre from iodine deficiency that resolved on 150 micrograms of iodine a day. — 1 young adult male with a restricted diet, USA (n = 1) Evidence D source
  TSH 24.4 mIU/L at presentation, normalized to 0.7 mIU/L on 150 mcg iodine daily

The bottom line

For blood sugar the evidence is small and old. In 15 healthy adults in Hong Kong, jam and peanut butter toast was classed as a high glycemic index food, and the value itself is not in the abstract. In a 1986 crossover, a 265 calories snack of peanut butter sandwich with chocolate milk gave glucose and insulin responses similar to those of single snacks, and the number of people is not given. In 15 obese women at high risk of type 2 diabetes, adding 1.5 oz (42.5 g) of peanut butter to a 75 g carbohydrate breakfast lowered blood glucose after the next meal, on a single day and at a dose larger than a typical sandwich carries. Nuts eaten with bread held back its iron. In a 1988 radioisotope trial in 137 Indian women, bread meals with nuts, peanuts among them, gave 1.8 percent iron absorption against 6.6 percent from bread alone, and 50 mg of vitamin C canceled the effect for peanuts. A review of 21 studies found that the body gets less energy from nuts than label factors predict, and more from nut butter than from roasted or raw nuts, though it gives no figure for peanuts. Roasting cut aflatoxin B1 by 46.91 percent across 19 laboratory processing experiments, mostly on peanuts. That is a cut from the starting level and says nothing about reaching a safe one. Europe refused to authorize the label claim that two tablespoons of peanut butter a day helps achieve healthy cholesterol levels. Peanut allergy is the first caution, and the infant trials above are the evidence on it, and they say nothing about how to introduce peanut to a baby at home. Among 60 toddlers in Jersey City homes with lead paint and dust, eating peanut butter and jelly sandwiches was associated with higher blood lead at 25 to 36 months, a cross-sectional finding in which the food marks hand-to-mouth eating and is not itself a lead source. A young man who ate mostly strawberries and peanut butter sandwiches, with no dairy or seafood, developed an iodine deficiency goitre that resolved on 150 micrograms of iodine a day, a single case about a monotonous diet. In 792 seven-year-old twins, daily peanut butter and jelly intake was 79 percent heritable in boys and not significantly so in girls, from one 24-hour recall. We have no card on pregnancy or medicines for this sandwich.

Sources

1. pbj-r6-01 · USDA FNDDS, dataset
   Peanut butter and jelly sandwich, NFS (FNDDS 42302010, fdc_id 2707554): Energy 361 KCAL; Protein 11.42 G; Total lipid (fat) 16.6 G; Carbohydrate, by difference 45.22 G; Fiber, total dietary 2.8 G; Sodium, Na 368 MG per 100 g; 1 sandwich 112 g
   USDA FNDDS, FDC 2707554 (food code 42302010) · checked 2026-09-29
2. pbj-r6-02 · USDA FNDDS, dataset
   Peanut butter and jelly sandwich, NFS (FNDDS 42302010, fdc_id 2707554): 1 sandwich 112 g; 1 sandwich (1 slice bread) 56 g; Quantity not specified 112 g | Peanut butter and jelly (fdc_id 2707543): Guideline amount per slice of bread/roll 16 g; 1 tablespoon 16 g
   USDA FNDDS, FDC 2707554 (food code 42302010) and FDC 2707543 · checked 2026-09-29
3. pbj-r6-05 · RCT
   Postprandial NEFA incremental AUC (IAUC) (0-240 min) and glucose IAUC (240-490 min) responses were lower for the PB breakfast compared with the control breakfast.
   Br J Nutr, 2013 · checked 2026-09-29
4. pbj-r6-08 · controlled clinical trial
   When the absorption from bread and nut meals (walnuts, almonds, peanuts, and hazelnuts) was compared with that from bread meals, the overall geometric mean absorption from the nut meals (1.8%) was significantly less than from the bread meals alone (6.6%, t = 9.8, p less than 0.0005)...Fifty milligrams ascorbic acid overcame the inhibitory effects of two nuts that were tested (Brazil nuts and peanuts).
   Am J Clin Nutr, 1988 · checked 2026-09-29
5. pbj-r6-09 · systematic review with narrative synthesis
   The ME of nuts was consistently lower than that predicted by Atwater factors for investigated nut types (almonds, cashews, hazelnuts, pistachios, walnuts, and peanuts)...ME was influenced by nut type (ME = 22.6 kJ/g for pistachios; ME = 18.5 kJ/g for raw almonds), physical form (flour > chopped > whole nuts), heat processing (butter > roasted > raw) and dose of consumption.
   Adv Nutr, 2023 · checked 2026-09-29
6. pbj-r6-10 · meta-analysis of in vitro processing experiments
   In most studies, the influence of method on aflatoxin reduction was assessed on peanuts...The results showed that the roasting method significantly reduced aflatoxin B1, B2, G1, and G2 concentrations by 46.91%, 30.66%, 40.88%, and 26.19%, respectively.
   Crit Rev Food Sci Nutr, 2022 · checked 2026-09-29
7. pbj-r6-03 · RCT
   Isocaloric snack meals of cereal-milk, cheese sandwich-milk, and peanut butter sandwich-chocolate milk produced glucose and insulin responses similar to individual snacks.
   Am J Clin Nutr, 1986 · checked 2026-09-29
8. pbj-r6-04 · RCT
   Among all the 23 Chinese traditional foods tested, 6 of them belonged to low GI foods (Tuna Fish Bun, Egg Tart, Green Bean Dessert, Chinese Herbal Jelly, Fried Rice Vermicelli in Singapore-style, and Spring Roll), 10 of them belonged to moderate GI foods (Baked Barbecued Pork Puff, Fried Fritter, "Mai-Lai" Cake, "Pineapple" Bun, Fried Rice Noodles with Sliced Beef, Barbecue Pork Bun, Moon Cakes, Glutinous Rice Ball, Instant Sweet Milky Bun, and Salted Meat Rice Dumpling), the others belonged to high GI foods (Fried Rice in Yangzhou-Style, Sticky Rice Wrapped in Lotus Leaf, Steamed Glutinous Rice Roll, Jam and Peanut Butter Toast, Plain Steamed Vermicelli Roll, Red Bean Dessert, and Frozen Sweet Milky Bun).
   World J Gastroenterol, 2010 · checked 2026-09-29
9. pbj-r6-06 · meta-analysis of randomized controlled trials
   We found high to moderate certainty evidence suggested that early introduction of allergen-containing foods reduces the risk of multiple food allergies (4 RCTs, 3854 participants, RR 0.49, 95% CI 0.33 to 0.74), egg (8 RCTs, 5193 participants, RR 0.58, 95% CI 0.44 to 0.78), peanut (3 RCTs, 4183 participants, RR 0.31, 95% CI 0.17 to 0.54) and atopic dermatitis or eczema (4 RCTs, 3579 participants, RR 0.88, 95% CI 0.78 to 1.00).
   BMJ Evid Based Med, 2024 · checked 2026-09-29
10. pbj-r6-12 · cross-sectional study
    For children 25-36 months old, eating hamburgers and peanut butter and jelly sandwiches was associated with elevated blood lead levels, while yogurt consumption was associated with lower blood lead levels.
    J Expo Anal Environ Epidemiol, 1997 · checked 2026-09-29
11. pbj-r6-11 · regulatory register entry
    POL-HC-7733 Peanuts, Peanut butter, Peanut oil Consuming a small handful, about 30 grams, of peanuts a day as part of a diet low in saturated fat helps to achieve healthy cholesterol levels and promotes heart health. Consuming two tablespoons, about 30g, of peanut butter a day as part of a diet low in saturated fat helps to achieve healthy cholesterol levels and promotes heart health. Consuming two tablespoons, about 30 grams of peanut oil a day as part of a diet low in saturated fat helps to achieve healthy cholesterol levels and promotes heart health. Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-7733, snapshot 2026-09-21 · checked 2026-09-29
12. pbj-r6-13 · twin study
    Seven categories showed significant heritability estimates among boys, ranging from 12% (fish and lemon) to 79% (peanut butter and jelly).
    Am J Clin Nutr, 2008 · checked 2026-09-29
13. pbj-r6-07 · systematic review and meta-analysis of randomized controlled trials
    The systematic review found no conclusive relationship between early peanut introduction and peanut allergy, nor the correlation between early cow's milk protein introduction and cow's milk protein allergy (P>0.05).
    Zhonghua Er Ke Za Zhi, 2021 · checked 2026-09-29
14. pbj-r6-14 · case report
    He reported consuming strawberries and peanut butter sandwiches with no intake of dairy or seafood due to gastrointestinal issues (abdominal pain, bloating, and nausea).
    AACE Clin Case Rep, 2020 · checked 2026-09-29