Rice noodles: a low GI result, and a toxin risk in wet noodles

Rice noodles came out as a low glycemic index food in a randomized crossover test of 14 healthy UK adults eating 50 g carbohydrate portions, among ten rice products that ranged from GI 37 to 92, though the abstract does not give the noodles' own value. Boiled, they are mostly water and starch. One UK product row gives 89 calories, 21.3 g carbohydrate, 1.9 g protein, 0.2 g fat and 1.1 g fiber per 3.5 oz (100 g), with 4 mg sodium when cooked in unsalted water. The US dietary survey counts a cup of cooked rice noodles as 175 g, about 187 calories and 42 g carbohydrate, figures recalculated from its per 3.5 oz (100 g) values. The serious record is on safety. Case reports from Taiwan and southern China describe deaths from bongkrekic acid poisoning after eating rice noodles: 2 of 33 patients in a 2024 Taipei outbreak, where the first reported case had eaten wet rice noodles, and 3 of 5 victims in Guangdong. We hold no card on how wet rice noodles should be bought or stored, or on whether cooking removes the toxin, so this page gives no such step.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• Boiled fine rice noodles have 89 calories, 21.3 g carbohydrate (all starch), 1.9 g protein, 0.2 g fat and 1.1 g fiber per 3.5 oz (100 g) in the UK composition table, with only 4 mg sodium when cooked in unsalted water. — CoFID 2021, code 11-725, noodles, rice, fine, dried, boiled in unsalted water Evidence E source
  89 calories, carbohydrate 21.3 g, starch 21.3 g, protein 1.9 g, fat 0.2 g, fiber 1.1 g, sodium 4 mg, water 73.2 g per 3.5 oz (100 g)
• A cup of cooked rice noodles is coded as 175 g in the US dietary survey, about 187 calories and 42 g carbohydrate. — USDA FNDDS, Rice noodles, cooked (code 56117090) Evidence E source
  Per 100 g 107 calories and 23.87 g carbohydrate; 1 cup 175 g = 187.2 calories, 41.8 g carbohydrate

What a real portion looks like

• Cooking roughly triples to quadruples the weight of rice noodles: the US survey codes 1 oz (28 g) of dry rice noodles as yielding 100 g cooked. — USDA FNDDS, Rice noodles, cooked (code 56117090), portion 1 oz dry yields Evidence E source
  28 g dry to 100 g cooked (about 3.5 times)

What your body absorbs

• Replacing 30% of wheat flour with RD43 rice flour made noodles with less rapidly digestible starch and lower blood glucose from 15 to 90 minutes after eating in a small human trial. — healthy adults, single test meals of noodles with 30% RD43 rice flour vs control Evidence B source
  Lower postprandial glucose at 15-90 min; higher GLP-1 and PYY at 30 min

What cooking and storage change

• In GI tests of 23 Hong Kong dishes in 15 adults, preparation changed the result: Singapore-style fried rice vermicelli was low GI, fried rice noodles with beef moderate, and plain steamed vermicelli roll high. — healthy adults (8 men, 7 women), 23 test foods vs glucose (n = 15) Evidence B source
  Category only: low (fried vermicelli), moderate (fried rice noodles with beef), high (plain steamed vermicelli roll)

What it does to your health

• In a randomized crossover GI test in 14 healthy UK adults using 50 g carbohydrate portions, rice noodles came out as a low-GI food, among ten rice products ranging from GI 37 to 92. — healthy adults, mean age 38, 50 g available carbohydrate per test (n = 14) Evidence B source
  Rice noodles low GI; range across 10 rice foods 37-92

Safety, limits and interactions

• In a March 2024 bongkrekic acid outbreak in East Taipei, two of 33 patients died, and the first reported case had eaten wet rice noodles. — 33 patients with bongkrekic acid ingestion, East Taipei, March 2024 (n = 33) Evidence D source
  2 deaths among 33 patients
• Five people in Guangdong were poisoned by bongkrekic acid after eating rice noodles, and three of them died. — 5 victims of food-borne bongkrekic acid poisoning, Guangdong, China (n = 5) Evidence D source
  3 of 5 died
• Observational data tie a 2021 school outbreak of 198 food poisoning cases in Chongqing to Bacillus cereus in rice noodles from one manufacturer, with a relative risk of about 40. — students at two rural middle schools, Chongqing, 2021 (n = 198 cases) Evidence C source
  RR 39.63 for eating the rice noodles; B. cereus above 10^3 CFU/g in 7 noodle samples
• In 1181 food samples from southern China tested in 2020-2023, Bacillus cereus group bacteria were found in 45.7% of wheat or rice noodles, second only to cereal flour. — 1181 retail food samples, southern China, 2020-2023 (n = 1181 samples) Evidence C source
  Contamination 45.7% in wheat/rice noodles vs 55.8% in cereal flour; emetic ces genes in 1.7% of sequenced strains
• FDA says vomiting-type B. cereus outbreaks have generally been associated with rice products and advises keeping food refrigerated at 40 F or lower. Cooking may kill the bacteria but might not disable the toxin that causes vomiting. — General population (home food handling) (n = -) Evidence E source
  Refrigerate at 40 F or lower, cooking may not disable the emetic toxin

Who this works differently for

• In a randomized GI test in 12 adults, Vietnamese noodle products had GI 39 to 61 while Thai rices had 86 to 109, and values did not differ between Asian and Caucasian subjects. — 6 Asian and 6 Caucasian healthy adults, 50 g carbohydrate portions (n = 12) Evidence B source
  Noodle products GI 39-61 vs rices 86-109; no difference by ethnic group (P=0.26)
• In a crossover RCT in 8 patients with reflux plus IBS, wheat noodle meals caused about 5.0 reflux-linked sphincter relaxations in 2 hours versus 1.9 after rice noodles, with more bloating and belching. — patients with overlapping GERD and non-constipation IBS, 250 g noodles at breakfast and lunch (n = 8) Evidence B source
  TLESR 5.0 ± 0.7 (wheat) vs 1.9 ± 0.3 (rice) per 2 h, p = 0.01; bloating 7.0 vs 3.1
• Among 888 first-trimester pregnant women in Changsha, rice noodles or noodles were the most common take-out food, eaten by 55.7% of take-out users. — 888 pregnant women under 14 weeks, Changsha, China, 2022 (n = 888) Evidence C source
  73.3% ate take-out; rice noodles or noodles 55.7%

What is still unknown

• A 13-year Japanese cohort of 5229 adults found no link between rice, noodle or bread intake and atrial fibrillation, and no study in the corpus tracks rice noodles alone against long-term disease. — Japanese urban adults, mean age 56.9, mean 13.1 years follow-up (n = 5229) Evidence C source
  No association between staple foods and AF in men or women

The bottom line

How the noodles are served shifts the glycemic result. In Hong Kong tests of 23 dishes in 15 adults, Singapore-style fried rice vermicelli came out low GI, fried rice noodles with beef moderate and plain steamed vermicelli roll high, and those dishes differ in fat and protein as well as in cooking. In a randomized test in 12 healthy adults, three Vietnamese noodle products scored GI 39 to 61 and three rices 86 to 109, with single tests per food and no difference between the 6 Asian and 6 Caucasian volunteers. A noodle with 30% of its wheat flour swapped for a rice flour called RD43 gave lower blood glucose from 15 to 90 minutes after eating in a small human test. That was a mostly wheat noodle made for the study, and the abstract does not give the number of participants. In 8 patients with both reflux and IBS, a day of wheat noodle meals was followed by 5.0 reflux-linked relaxations of the lower esophageal sphincter in the 2 hours after lunch, against 1.9 after rice noodles, in a single-day crossover trial. Cooking also changes the weight: the US survey codes 0.99 oz (28 g) of dry rice noodles as yielding 100 g cooked, a coding convention, since water uptake varies with noodle width and time. Who should be careful. Bongkrekic acid poisoning killed 3 of the 5 people in the Guangdong cases and 2 of the 33 patients in Taipei. These are case series. Bacillus cereus is the other documented risk. A 2021 outbreak at two rural middle schools in Chongqing, with 198 cases, was traced to rice noodles from one manufacturer (RR 39.63 for eating them), in a single outbreak. In 1181 food samples from southern China tested in 2020 to 2023, Bacillus cereus group bacteria turned up in 45.7% of wheat or rice noodles, a figure that records presence and pools the two noodle types. We hold no card on cooling and storing cooked noodles, so this page gives no rule for leftovers. The only card on pregnancy is a survey of 888 pregnant women in Changsha, where rice noodles or noodles were the most common take-out food, eaten by 55.7% of take-out users, and it measured habits with no health outcome, including no link to the poisoning risks above. We have no card on allergy or medicines. A 13-year Japanese cohort of 5229 adults found no link between rice, noodle or bread intake and atrial fibrillation, and it did not split rice noodles from wheat noodles. We found no study that tracks rice noodles alone against long-term disease.

Sources

1. rcnd-daily-r1-01 · reference dataset
   CoFID 11-725 Noodles, rice, fine, dried, boiled in unsalted water: Energy 89 kcal · Carbohydrate 21.3 g · Starch 21.3 g · Protein 1.9 g · Fat 0.2 g · AOAC fibre 1.1 g · Sodium 4 mg · Water 73.2 g
   CoFID 2021, Public Health England (OGL v3.0), code 11-725 · checked 2026-09-29
2. rcnd-daily-r1-02 · reference dataset
   FNDDS 56117090 Rice noodles, cooked (fdc 2708356): Energy 107 kcal per 100 g · Carbohydrate, by difference 23.87 g per 100 g · 1 cup, cooked 175 g
   USDA FNDDS 2021-2023 (FoodData Central), code 56117090 · checked 2026-09-29
3. rcnd-daily-r1-03 · reference dataset
   FNDDS 56117090 Rice noodles, cooked (fdc 2708356): 1 oz, dry, yields 100 g
   USDA FNDDS 2021-2023 (FoodData Central), code 56117090 · checked 2026-09-29
4. rcnd-daily-r1-08 · RCT (test meal)
   The results demonstrated that the substitution of 10-40% RD43 rice flour reduced starch digestibility, the hydrolysis index, and rapidly digestible starch (RDS), while increasing undigestible starch in noodles. ... In human studies, ingestion of 30% RD43 rice noodles significantly lowered postprandial plasma glucose at 15-90 min.
   Food Funct, 2021 · checked 2026-09-29
5. rcnd-daily-r1-06 · RCT (GI test)
   Fifteen healthy subjects (8 males and 7 females) volunteered to consume either glucose or one of 23 test foods after 10-14 h overnight fast. ... 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
6. rcnd-daily-r1-04 · RCT, crossover (GI test)
   Fourteen healthy subjects (six males, eight females), mean age 38 (standard deviation 16) years and mean body mass index 21.3 (standard deviation 2.3) kg/m(2), were recruited for the study. ... The 10 foods exhibited a range of GI values from 37 to 92. The study indicated that rice noodles, long-grain rice, easy-cook long-grain rice and white basmati rice were low-GI foods
   Int J Food Sci Nutr, 2009 · checked 2026-09-29
7. rcnd-daily-r1-09 · case series
   Herein, we report two fatalities among 33 patients who ingested BKA in March 2024, East Taipei, Taiwan. CASE REPORT: Our first case involved a 40-year-old female who presented with nausea, vomiting, and diarrhea after consuming wet rice noodles.
   Taiwan J Obstet Gynecol, 2025 · checked 2026-09-29
8. rcnd-daily-r1-10 · case series
   For the first time, we retrospectively report five cases of food-borne poisoning caused by eating rice noodles, a popular traditional food in Guangdong, China, and three of the victims died.
   Leg Med (Tokyo), 2019 · checked 2026-09-29
9. rcnd-daily-r1-11 · retrospective cohort
   A total of 198 cases were reported in this outbreak, with an attack rate of 24.63%. ... The retrospective cohort study showed a significant association between the outbreak and rice noodles provided by a nearby food manufacturer (RR = 39.63, p < 0.001).
   PLoS One, 2023 · checked 2026-09-29
10. rcnd-daily-r1-12 · prevalence survey
    A total of 890 strains of B. cereus group bacteria from 1181 food samples from 2020 to 2023 were identified using the standardized detection method. These strains were found to be prevalent in various food types, with the highest contamination rates observed in cereal flour (55.8 %) and wheat/rice noodles (45.7 %).
    Sci Total Environ, 2024 · checked 2026-09-29
11. sf-bc-r3-4 · agency advice
    The vomiting-type outbreaks generally have been associated with rice products; however, other starchy foods, such as potato, pasta, and cheese products, also have been implicated. Food mixtures, such as sauces, puddings, soups, casseroles, pastries, and salads, frequently have been linked with food-poisoning outbreaks. ... One of the most important things you can do to protect yourself from infection with B. cereus is to keep your food refrigerated at 40°F or lower. ... Cooking may kill the bacteria, but it might not disable the toxin that causes the vomiting type of illness.
    US FDA, Bad Bug Book 2nd ed. (2012), Bacillus cereus and other Bacillus species · checked 2026-10-08
12. rcnd-daily-r1-05 · RCT (GI test)
    Twelve healthy subjects (six Asian and six Caucasian) consumed 50 g carbohydrate portions of a reference food (glucose sugar) and nine Vietnamese foods (three rices, three noodle products and three sweet foods) in random order after an overnight fast. ... The three rices had surprisingly high GI values (86-109), whereas the noodle products had relatively low GI values (39-61). ... The GI values for the nine foods calculated separately for the two racial groups were not significantly different from each other (P=0.26).
    Eur J Clin Nutr, 2001 · checked 2026-09-29
13. rcnd-daily-r1-07 · RCT, crossover
    A randomized crossover study in eight patients (6 F, age 57 ± 13) with overlapping GERD-IBS (non-constipation) was conducted to evaluate the effects of rice noodle vs. wheat noodle meals for breakfast and lunch on postprandial TLESR, intestinal gas production, and GERD/GI symptoms. Results: Wheat ingestion was significantly associated with more frequent TLESR after lunch than rice (5.0 ± 0.7 vs. 1.9 ± 0.3 times/2 h, p = 0.01).
    Nutrients, 2022 · checked 2026-09-29
14. rcnd-daily-r1-13 · cross-sectional
    In Changsha, 73.3% of pregnant women consumed take-out food during early pregnancy. The top three types of take-out foods commonly consumed were rice noodles or noodles (55.7%), Chinese fast foods (49.9%), and sugary drinks or desserts (37.4%).
    BMC Public Health, 2025 · checked 2026-09-29
15. rcnd-daily-r1-14 · cohort
    Our population-based prospective cohort study included 5229 adult participants (mean age 56.9 years; 46.5% men) who completed a Food Frequency Questionnaire. ... We found no association between staple foods and AF risk in men or women.
    BMJ Open, 2026 · checked 2026-09-29