Peanut brittle: mostly sugar, and a serious peanut allergen

The strongest finding connected to peanut brittle concerns its peanuts and says nothing about the candy. A meta-analysis of 3 randomized trials in 4,183 infants found that introducing peanut early in infancy cut the risk of peanut allergy by about 69 percent, a risk ratio of 0.31 with a 95 percent confidence interval of 0.17 to 0.54. That evidence is about peanut protein in forms suited to infants, and hard brittle is no food for babies or young children because of the choking risk. Ask the child's doctor before a baby has peanut for the first time. What brittle itself delivers is sugar. A UK homemade recipe lists 483 calories and 71.8 g of total sugars per 3.5 oz (100 g), 64.2 g of it sucrose, with 8.6 g of protein. The US survey code lists 486 calories and 51.3 g of sugars per 3.5 oz (100 g), so recipes clearly differ. One 10 g piece gives about 49 calories and 5.1 g of sugars.

How much is actually in it

• Homemade peanut brittle provides 483 calories per 3.5 oz (100 g), with 71.8 g total sugars (64.2 g sucrose), 19 g fat and 8.6 g protein. — UK food composition record, peanut brittle, homemade Evidence E source
  483 calories, 71.8 g sugars, 19.0 g fat, 5.3 g saturated fat, 8.6 g protein, 110 mg sodium per 3.5 oz (100 g)

What a real portion looks like

• In US survey data, one 10 g piece of peanut brittle gives about 49 calories and 5.1 g sugars, and an unspecified 1.1 oz (30 g) portion about 146 calories and 15.4 g sugars. — US survey food code, candy, peanut brittle Evidence E source
  486 calories and 51.33 g total sugars per 3.5 oz (100 g); 1 piece 10 g; 1 cup 160 g = 778 calories

What your body absorbs

• In a randomized crossover trial in 61 older overweight adults, eating high oleic peanuts for 12 weeks raised energy intake by 10% but weight rose only 1.1 lb (0.5 kg), less than predicted. — 61 healthy adults, 65 +/- 7 years, BMI 31, 12-week phases (n = 61) Evidence B source
  Energy intake +853 kJ (10%); no change in body composition; weight +1.1 lb (0.5 kg), below prediction
• In 137 Indian women, iron absorption from bread meals with nuts including peanuts was 1.8% versus 6.6% from bread alone. — 137 Indian women, single test meals (n = 137) Evidence C source
  Geometric mean iron absorption 1.8% (nut meals) vs 6.6% (bread), p < 0.0005

What cooking and storage change

• Laboratory data pooled from 19 trials suggest roasting cuts aflatoxin B1 in nuts, mostly peanuts, by about 47%. — 19 interventional laboratory studies on nuts, mostly peanuts (n = 19 studies) Evidence D source
  Aflatoxin B1 -46.91%, B2 -30.66%, G1 -40.88%, G2 -26.19% after roasting
• A systematic review of 21 human and in vitro studies found the usable energy of nuts, including peanuts, is lower than label factors predict, and rises with processing from raw to roasted to butter. — 21 human (adults) and in vitro studies on tree nuts and peanuts (n = 21 studies) Evidence C source
  Metabolizable energy below Atwater prediction; heat processing order butter > roasted > raw

Safety, limits and interactions

• Food challenge data show that about 2 mg of peanut protein triggers objective reactions in 5% of peanut-allergic people. — peanut-allergic individuals in over 3000 double-blind food challenges (n = 3000+) Evidence C source
  Discrete ED05 2.1 mg protein (95% CI 1.2-4.6); anaphylaxis in 4.5% of those reacting at this level

What people believe that the data does not support

• The EU did not authorize the claim that about 1.1 oz (30 g) of peanuts a day helps achieve healthy cholesterol levels and heart health. — EU nutrition and health claims register Evidence E source
  Non-authorized

Who this works differently for

• A meta-analysis of 3 RCTs in 4,183 infants found early peanut introduction in infancy cut peanut allergy risk by about 69% (RR 0.31). — infants in 3 RCTs, introduction before 12 months (n = 4183) Evidence A source
  RR 0.31, 95% CI 0.17 to 0.54
• Observational data pooled across 190 studies link introducing peanut after 12 months of age with higher odds of childhood food allergy (OR 2.55). — children under 6 years, 190 studies, 2.8 million participants (n = 2.8 million) Evidence C source
  OR 2.55; risk difference 6.8%, 95% CI 1.9% to 14.6%
• The CDC lists hard candy and whole or chopped nuts among potential choking hazards for young children. — Infants and young children (n = -) Evidence E source
  Listed as foods to avoid for young children (choking risk)

What is still unknown

• The systematic review of 21 nut energy studies says further clinical trials are needed before its findings can guide dietetics. — 21 human and in vitro studies (n = 21 studies) Evidence C source
  Knowledge gap

The bottom line

For anyone allergic to peanut, brittle is a real risk. Pooled data from over 3,000 double-blind food challenges put the dose that triggers objective reactions in 5 percent of peanut-allergic people at 2.1 mg of peanut protein, with a 95 percent confidence interval of 1.2 to 4.6 mg. One bite of brittle holds far more protein than that, which is our inference from the protein value of the recipe and was never tested on brittle. Observational data pooled across 190 studies link introducing peanut after 12 months of age with higher odds of childhood food allergy, an odds ratio of 2.55 and a risk difference of 6.8 percent, with a 95 percent confidence interval of 1.9 to 14.6 percent. Roasting lowers aflatoxin in nuts. Laboratory data pooled from 19 studies, mostly on peanuts, show roasting cut aflatoxin B1 by about 47 percent, with roasting conditions varying and no human outcome measured. Peanuts may count for fewer calories than the label predicts. A systematic review of 21 human and in vitro studies found the usable energy of nuts, peanuts included, sits below label factors and rises from raw to roasted to butter. It pooled no numbers and studied no peanuts set in sugar. In a randomized crossover trial in 61 adults aged about 65 with an average BMI of 31, eating high oleic peanuts for 12 weeks raised energy intake by 10 percent, while weight rose only 1.1 lb (0.5 kg), less than predicted. Those were plain peanuts. In 137 Indian women given single test meals in 1988, iron absorption from bread with nuts including peanuts was 1.8 percent, against 6.6 percent from bread alone. The EU did not authorize a claim that about 1.1 oz (30 g) of peanuts a day helps achieve healthy cholesterol levels, which means the evidence was judged insufficient when it was assessed. We found no study of peanut brittle itself, and the nut energy review says further clinical trials are needed before its findings can guide dietetics.

Sources

1. pnbr-daily-r6-01 · CoFID dataset
   Peanut brittle, homemade, CoFID code 17-116: Energy (kcal) 483, Total sugars (g) 71.8, Sucrose (g) 64.2, Fat (g) 19.0, Satd FA (g) 5.30, Protein (g) 8.6, Sodium (mg) 110 per 100 g
   CoFID 2021, Public Health England, code 17-116 (Peanut brittle, homemade) · checked 2026-09-30
2. pnbr-daily-r6-02 · USDA FNDDS dataset
   Candy, peanut brittle, fdc_id 2710357: Energy 486 KCAL, Total Sugars 51.33 G per 100 g; 1 piece 10 g; 1 cup 160 g; Quantity not specified 30 g
   USDA FNDDS 2021-2023, Candy, peanut brittle (FDC 2710357) · checked 2026-09-30
3. pnbr-daily-r6-05 · randomized crossover trial
   Despite greater energy intake during the peanut phase, there were no differences in body composition, and less than predicted increase (0.5 kg) in body weight for this additional energy intake, possibly due to incomplete nutrient absorption and energy utilisation.
   Nutrients, 2015 · checked 2026-09-30
4. pnbr-daily-r6-06 · 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).
   Am J Clin Nutr, 1988 · checked 2026-09-30
5. pnbr-daily-r6-03 · systematic review and meta-analysis
   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 2026-09-30
6. pnbr-daily-r6-04 · systematic review
   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 2026-09-30
7. pnbr-daily-r6-09 · meta-analysis of food challenges
   The cumulative ED01 and ED05 for peanut is 0.7 (95% CI: 0.5-1.3) mg of protein and 3.9 (95% CI: 2.8-7.1) mg of protein, respectively; the discrete ED05 is 2.1 (95% CI: 1.2-4.6) mg of protein.
   J Allergy Clin Immunol Pract, 2022 · checked 2026-09-30
8. pnbr-daily-r6-10 · regulatory register
   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 2026-09-30
9. pnbr-daily-r6-07 · meta-analysis of RCTs
   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 2026-09-30
10. pnbr-daily-r6-08 · systematic review and meta-analysis
    delayed solid food introduction (eg, peanut after age 12 months [OR, 2.55; RD, 6.8%; 95% CI, 1.9%-14.6%])
    JAMA Pediatr, 2026 · checked 2026-09-30
11. sf-choke-r2-5 · agency advice
    Round or hard candy, jelly beans, caramels, gum drops, or gummy candies. ... Whole or chopped nuts and seeds.
    CDC, Infant and Toddler Nutrition: Choking Hazards · checked 2026-10-08
12. pnbr-daily-r6-11 · systematic review
    However, the strength of the evidence base was reduced by the variation in methods used between studies, suggesting that further clinical trials are needed to determine the impact of the findings of this review for clinical dietetics.
    Adv Nutr, 2023 · checked 2026-09-30