Chestnuts: the starchy nut with almost no fat

The one meta-analysis we found that includes chestnuts pooled them with almonds, peanuts, walnuts and other nuts. Across 27 studies with 1121 adults, eating nuts raised resting energy use by 28.6 calories a day, a change that did not reach significance (95% CI -10.7 to 67.8), and there is no result for chestnuts on their own. What sets chestnuts apart is the composition. Per 100 g, roasted European chestnuts give 245 calories, 52.96 g carbohydrate and only 2.2 g fat, with 5.1 g fiber, 592 mg potassium and 26 mg vitamin C, from a single USDA record with no sample range. One nut weighs about 8 g in the US survey database, so a 0.99 oz (28 g) serving is three or four nuts. In a trial where 24 young adults ate 500 calories preloads in random order, chestnuts lowered hunger over the next three hours as much as peanuts, almonds or chocolate of the same calories.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• Roasted European chestnuts give about 245 calories per 3.5 oz (100 g), mostly starch, with only 2.2 g fat and 26 mg vitamin C, unlike most other nuts. — USDA SR Legacy, Nuts, chestnuts, european, roasted (FDC 170190) (n = 1 record) Evidence E source
  245 calories, carbohydrate 52.96 g, fat 2.2 g, fiber 5.1 g, vitamin C 26 mg, potassium 592 mg per 3.5 oz (100 g)
• Tables disagree on raw chestnuts: USDA lists 40.2 mg vitamin C and 196 calories per 3.5 oz (100 g), while the UK table lists only a trace of vitamin C and 170 calories. — USDA SR Legacy FDC 170575 vs CoFID 2021 code 14-813, raw peeled kernels (n = 2 records) Evidence E source
  Vitamin C 40.2 mg vs trace; energy 196 vs 170 calories; potassium 484 vs 500 mg per 3.5 oz (100 g)

What a real portion looks like

• The US survey food database counts one chestnut as 8 g, so a 0.99 oz (28 g) serving is about three to four nuts, and a cup weighs 5 oz (143 g). — FNDDS food code 42105000, Chestnuts (n = 4 portion measures) Evidence E source
  1 nut 8 g; 1 oz 28 g; 1 cup 143 g; quantity not specified 28 g
• In a Korean national survey of 12113 adults, chestnuts were the most eaten nut, though only about 0.95 g a day on average. — Korean adults aged 19-64, KNHANES 2016-2019, 24-hour recall (n = 12113) Evidence C source
  Chestnut intake 0.95 g/day, highest among 20 nuts

What cooking and storage change

• By USDA retention factors for nuts, roasting or boiling keeps about 80% of vitamin C and folate and 85% of thiamin, while minerals stay at 100%. — USDA Table of Nutrient Retention Factors R6, Nut and Seed Products group, roasted (2203) and boiled (2204) (n = 2 methods) Evidence E source
  Vitamin C 80%, folate 80%, thiamin 85%, vitamin B6 95%, copper and potassium 100% retained
• Lab data suggest that heating destroys the class I chitinase allergens behind latex-fruit syndrome, though this was shown for avocado and green bean proteins, not chestnut itself. — Purified avocado and green bean chitinases, sera and skin tests from latex-fruit allergic patients (n = 8) Evidence D source
  Full loss of allergenic capacity after heating, in vitro and in vivo

What it does to your health

• A meta-analysis of 27 studies with 1121 adults, covering nuts including chestnuts, found that eating nuts raised resting energy use by only a non-significant 28.6 calories a day. — Adults aged 18 and over, 27 studies of tree nuts and peanuts including chestnuts (n = 1121) Evidence A source
  REE weighted mean difference 28.6 calories/d (95% CI -10.7 to 67.8)
• In a trial with 24 adults eating 500 calories preloads in random order, chestnuts cut hunger as much as peanuts, almonds or chocolate of equal calories. — 12 men and 12 women, healthy normal weight, mean age 22 (n = 24) Evidence B source
  Hunger after 500 calories chestnut preload lower than low-energy or no preload, not different from other 500 calories preloads

Safety, limits and interactions

• Lab data suggest that in people allergic to chestnut but not latex, the main allergen is a lipid transfer protein, Cas s 8, found in 58-91% of their blood samples. — 12 patients sensitized to chestnut but not latex, 3 latex-chestnut controls (n = 15) Evidence D source
  IgE to Cas s 8 in 91% (immunoblot) and 58% (ELISA); positive skin test 66%

What people believe that the data does not support

• Plant drinks such as sweet chestnut milk are not a substitute for infant formula: French doctors reported nine infants with severe deficiencies after using rice, soy, almond and chestnut milks. — 9 infants aged 4-14 months, France, 2008-2011 (n = 9) Evidence D source
  Protein-calorie malnutrition in 3, iron deficiency anemia in 5, rickets in 3
• Since January 2025 the FDA no longer lists chestnut among tree nuts that must be declared as major food allergens on US labels. — US food allergen labeling, FDA guidance Edition 5 (January 2025) Evidence E source
  Chestnut removed from the tree nut major allergen list

Who this works differently for

• Lab and skin test data suggest people with latex allergy can react to chestnut: a chestnut chitinase gave positive skin tests in 13 of 18 patients with latex-fruit allergy. — 18 latex-allergic patients allergic to chestnut, avocado or both (n = 18) Evidence D source
  Positive skin prick test to chestnut class I chitinase in 72%
• Among 137 people with latex allergy, 21% reported food reactions, but chestnut accounted for only one of 49 reactions (2%). — 137 patients with type I latex allergy (n = 137) Evidence C source
  Chestnut 1 of 49 reactions (2.0%); banana 18.3%, avocado 16.3%
• A rare case report describes a 63-year-old woman who twice had small bowel obstruction after eating chestnuts. — One woman aged 63, Japan (n = 1) Evidence D source
  Two episodes of small bowel obstruction

What is still unknown

• Chestnut allergy has mostly been studied as part of latex-fruit syndrome, and allergens unrelated to latex were largely unexplored until 2006. — Chestnut allergy research Evidence D source
  —

The bottom line

Vitamin C is the uncertain number. USDA lists 40.2 mg per 3.5 oz (100 g) in raw peeled European chestnuts, while the UK table lists only a trace for raw kernels, which likely reflects different varieties, storage and lab methods. USDA retention factors for roasted or boiled nuts keep about 80% of vitamin C and folate and all the potassium, though those factors were set for nuts as a group in 1975 and never measured on chestnuts. We found no human study of how well chestnut starch is digested. In a Korean national survey of 12113 adults chestnuts were the most eaten nut at 0.95 g a day, an average that counts everyone who ate none that day. Allergy is the real caution. In 12 people allergic to chestnut without latex allergy, lab tests found IgE to the lipid transfer protein Cas s 8 in 91% of blood samples by immunoblot and 58% by ELISA, a small laboratory study. People with latex allergy can react too. A chestnut chitinase gave positive skin tests in 13 of 18 selected patients with latex-fruit allergy. Among 137 latex-allergic patients asked about their history, chestnut caused only one of 49 food reactions. Heating destroyed the same class of allergen in lab work on avocado and green bean proteins, and nobody has tested it on chestnut. Since January 2025 the FDA no longer counts chestnut as a major allergen that US labels must declare. That changes the label rule and says nothing about how many people react, so if you are allergic, read ingredient lists closely. One 63-year-old woman in Japan twice had small bowel obstruction after eating chestnuts, a single case. Chestnut milk is no infant formula. French doctors reported nine infants aged 4 to 14 months fed rice, soy, almond or chestnut drinks: three had severe protein-calorie malnutrition, five iron deficiency anemia and three rickets. Until 2006 chestnut allergy had been studied almost only as part of latex-fruit syndrome, and allergens unrelated to latex are still little explored.

Sources

1. cnut-daily-r7-01 · USDA SR Legacy 2019, dataset
   Nuts, chestnuts, european, roasted (FDC 170190, SR Legacy, 2019-04-01): energy 245 kcal, carbohydrate 52.96 g, fat 2.2 g, fiber 5.1 g, vitamin C 26 mg, potassium 592 mg, copper 0.507 mg per 100 g
   USDA FoodData Central, SR Legacy 2019, FDC 170190 · checked 2026-09-29
2. cnut-daily-r7-02 · USDA SR Legacy 2019 and CoFID 2021, dataset
   Nuts, chestnuts, european, raw, peeled (FDC 170575): vitamin C 40.2 mg, energy 196 kcal, potassium 484 mg per 100 g; Chestnuts, kernel only, raw (CoFID 14-813): vitamin C Tr, energy 170 kcal, potassium 500 mg per 100 g
   USDA SR Legacy 2019 FDC 170575; CoFID 2021, Public Health England / OGL v3.0, code 14-813 · checked 2026-09-29
3. cnut-daily-r7-03 · USDA FNDDS 2021-2023, dataset
   Chestnuts (FNDDS 42105000, FDC 2707499, WWEIA Nuts and seeds): 1 nut 8 g; 1 cup 143 g; 1 oz 28 g; Quantity not specified 28 g
   USDA FNDDS 2021-2023, food code 42105000 (FDC 2707499) · checked 2026-09-29
4. cnut-daily-r7-13 · cross-sectional
   Among nut intake, chestnuts represented the highest value at 0.95 g/day, followed by peanuts (0.72 g/day), almonds (0.62 g/day), sesame seeds (0.62 g/day), perilla seeds (0.33 g/day), and walnuts (0.32 g/day).
   Biol Trace Elem Res, 2022 · checked 2026-09-29
5. cnut-daily-r7-04 · USDA R6 2007, dataset
   USDA-RETN-R6:2203 NUTS,ROASTED (Nut and Seed Products): vitamin_c_mg 80%, folate_total_ug 80%, thiamin_mg 85%, vitamin_b6_mg 95%, copper_mg 100%; USDA-RETN-R6:2204 NUTS,BOILED,W/DRIPPINGS: vitamin_c_mg 80%, folate_total_ug 80%, thiamin_mg 85%, potassium_mg 100%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), codes 2203 and 2204 · checked 2026-09-29
6. cnut-daily-r7-09 · laboratory
   Heat treatment of both Prs a 1 and PvChI produced a full loss of their allergenic capacities both in vitro and in vivo.
   J Allergy Clin Immunol, 2000 · checked 2026-09-29
7. cnut-daily-r7-05 · meta-analysis
   Twenty-eight articles from 27 studies (16 energy intake studies, 10 EE studies, and 1 study investigating both) with 1121 participants were included in this review, with a variety of nut types addressed (almonds, Brazil nuts, cashews, chestnuts, hazelnuts, peanuts, pistachios, walnuts, and mixed nuts). ... The meta-analyses identified a nonsignificant increase in REE associated with nut consumption (weighted mean difference: 28.6 kcal/d; 95% CI: -10.7, 67.8 kcal/d).
   Adv Nutr, 2023 · checked 2026-09-29
8. cnut-daily-r7-06 · controlled crossover trial
   Hunger ratings following consumption of the 2092 kJ (500 kcal) preloads of peanuts, peanut butter, almonds, chestnuts and chocolate were significantly lower than the low energy preloads or no preload condition, but with the exception of peanut butter, did not vary from each other.
   Int J Obes Relat Metab Disord, 2000 · checked 2026-09-29
9. cnut-daily-r7-07 · allergen characterization
   Specific IgE to this allergen was found in 91% (by means of IgE immunoblotting) and 58% (by means of ELISA) of sera from patients with chestnut but not latex allergy.
   J Allergy Clin Immunol, 2006 · checked 2026-09-29
10. cnut-daily-r7-12 · case series
    The beverages consumed were rice, soya, almond and sweet chestnut milks. In three cases, infants presented severe protein-calorie malnutrition with substantial hypoalbuminemia (<20 g/L) and diffuse edema.
    Arch Pediatr, 2014 · checked 2026-09-29
11. cnut-daily-r7-15 · agency guidance
    In addition to coconut, other tree nuts that are no longer on the list of those considered major food allergens are beech nut, butternut, chestnut, chinquapin, cola/kola nut, ginkgo nut, hickory nut, palm nut, pili nut, shea nut, and lichee nut.
    US FDA, Frequently Asked Questions: Food Allergen Labeling Guidance for Industry, 2025 · checked 2026-09-29
12. cnut-daily-r7-08 · allergen characterization
    The chestnut class I chitinase elicited positive SPT responses in 13 of 18 patients with latex-fruit allergy (72%), and the avocado class I chitinase elicited positive responses in 12 of 18 (67%) similarly allergic patients.
    J Allergy Clin Immunol, 1999 · checked 2026-09-29
13. cnut-daily-r7-10 · prevalence survey
    Foods responsible for these reactions include banana 9 (18.3%), avocado 8 (16.3%), shellfish 6 (12.2%), fish 4 (8.1%), kiwi 6 (12.2%), tomato 3 (6.1%), watermelon, peach, carrot 2 (4.1%) each, and apple, chestnut, cherry, coconut, apricot, strawberry, loquat, one (2.0%) each.
    Allergy Asthma Proc, 1999 · checked 2026-09-29
14. cnut-daily-r7-11 · case report
    We present the case of 63-year-old woman who developed small bowel obstruction twice due to the ingestion of chestnuts without the formation of phytobezoars.
    Intern Med, 2016 · checked 2026-09-29
15. cnut-daily-r7-14 · allergen characterization
    Chestnut allergy has been almost exclusively considered in the context of the latex-fruit syndrome. Chestnut allergens not linked to latex hypersensitivity have not been studied.
    J Allergy Clin Immunol, 2006 · checked 2026-09-29