Rice crackers: few trials, small effects, and the arsenic of rice

The rice cracker is sold as the light snack, and the trials on it are few and small. In a randomized trial of 30 healthy adults, 10 per group, 2.4 oz (68 g) of crispy rice cracker eaten with breakfast was followed within 24 hours by lower Collinsella and Bifidobacterium in stool than lower-GI Thai desserts. That was a single serving, the abstract gives no effect size, and the authors say the shift may be temporary. In a trial in healthy adults and people with type 2 diabetes, plain rice crackers and whole grain buckwheat crackers gave similar blood glucose and insulin over 3 hours. Crackers that did lower the glucose and insulin rise in a crossover trial were made from a specially bred high resistant starch rice, and the abstract names neither the number of people nor the size of the change. The steadier finding is about what the cracker carries. A survey of retail rice products found crackers with arsenic at levels typical of rice grain, 75.2 to 90.1% of it inorganic, though the abstract gives no concentration for crackers alone.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• A survey of rice products including rice crackers found arsenic levels typical of rice grain, with 75.2 to 90.1% of it in the inorganic form. — retail rice products (crisped and puffed rice, rice crackers, noodles, condiments) Evidence C source
  Inorganic arsenic 75.2-90.1% of total arsenic
• Rice crackers contain 156 mg magnesium, 25.5 mcg selenium and 0.436 mg thiamin per 3.5 oz (100 g) in the USDA reference record. — food composition record, rice crackers Evidence E source
  Magnesium 156 mg, selenium 25.5 mcg, thiamin 0.436 mg per 3.5 oz (100 g)

What a real portion looks like

• In US survey food codes, one rice cracker weighs 3 g and an unspecified serving 18 g, giving about 7 mg and 42 mg sodium. — FNDDS food code for rice crackers Evidence E source
  1 cracker 3 g, 7.0 mg sodium; quantity not specified 18 g, 41.9 mg sodium; 1 cup 40 g

What your body absorbs

• In a randomized crossover trial in healthy adults, rice crackers made from a high resistant starch rice lowered the glucose and insulin rise after eating compared with crackers from ordinary rice. — healthy adults, single ingestion, crossover Evidence B source
  Lower incremental area under the curve for glucose and insulin vs usual-cultivar crackers, size not given in abstract

What it does to your health

• In a randomized trial of 30 healthy adults, eating 2.4 oz (68 g) of crispy rice cracker with breakfast was followed within 24 hours by lower Collinsella and Bifidobacterium abundance than lower-GI Thai desserts. — healthy adults aged 18 to 45, 10 per group, single serving with standard breakfast, stool sampled at 24 h (n = 30) Evidence B source
  Relative abundance of Collinsella and Bifidobacterium decreased vs low- and medium-GI groups, no effect size given; authors say effects may be temporary
• In a trial in healthy adults and people with type 2 diabetes, rice crackers and whole grain buckwheat crackers gave similar glucose and insulin over 3 hours, while gut satiety hormones differed. — healthy participants and adults with diet-controlled type 2 diabetes, single cracker meal, blood sampled to 180 min Evidence B source
  No difference in post-prandial glucose, insulin or C-peptide; GLP-1, GIP and pancreatic polypeptide altered

Safety, limits and interactions

• US survey data link eating rice cakes and crackers with higher urinary arsenic metabolites, most strongly in children and adolescents. — about 8,300 US participants aged 6 and over, NHANES 2003-2010 (n = 8300) Evidence C source
  Rice cakes/crackers had the largest association with urinary DMA in adolescents and with MMA in children and adolescents
• A case report found undeclared wheat in 3 of 8 retail rice crackers and a systemic reaction in a wheat-allergic infant after 9 g of crackers. — one wheat-allergic infant boy, plus 8 retail rice crackers tested (n = 1) Evidence D source
  Offending cracker 1.50 microg/g wheat protein, others 0.26-1.13 microg/g, about 13.5 microg elicited urticaria

Who this works differently for

• In a randomized trial in people with complete dentures, a soft silicone liner improved reported chewing of hard rice crackers, but only after 3 months. — completely edentulous patients fitted with new complete dentures Evidence B source
  Difference between relined and conventional dentures appeared at 3 months, not at final adjustment
• In 105 patients with swallowing problems given a rice cracker chewing test, 92.4% ate it without aspiration. — patients with dysphagia, mostly older adults (n = 105) Evidence C source
  92.4% no aspiration on videoendoscopy
• Among 482 independently living 70-year-olds, about 15% had trouble chewing foods such as hard rice crackers, linked to deeper gum pockets. — independently living 69-71-year-olds with no mobile teeth, Japan (n = 482) Evidence C source
  About 15% in compromised food acceptability group, associated with periodontal probing depth
• In 708 community-dwelling older adults, the number of foods such as hard rice crackers they could eat without difficulty best explained dissatisfaction with chewing. — community-dwelling adults, mean age 66, 351 men and 357 women (n = 708) Evidence C source
  Number of foods eaten without difficulty was the strongest explanatory variable (P < .01)

The bottom line

Across about 8,300 Americans aged 6 and over, rice cakes and crackers had the largest association of any food with the arsenic metabolite DMA in adolescents, and with MMA in children and adolescents. This is a link with urine levels from a 24-hour food recall. It says nothing yet about illness. The caution that follows from it is about children and adolescents, in whom the link was strongest. The USDA record lists 156 mg magnesium, 25.5 mcg selenium and 0.436 mg thiamin per 3.5 oz (100 g), from one sample with no spread reported. A single cracker weighs about 3 g and an unspecified serving 18 g, which works out to about 7 mg and 42 mg of sodium when recalculated from 233 mg per 3.5 oz (100 g). Salted and flavored kinds can differ. For wheat allergy, one Japanese case report from 2004 found undeclared wheat protein in 3 of 8 retail rice crackers, and a wheat-allergic infant had a systemic reaction after 9 g of crackers, about 13.5 microg of wheat protein. It is one case, but it means "rice" on the pack is no guarantee for a highly sensitive child. We found no study on pregnancy or kidney disease. Hard rice crackers turn up in dental research as a test of chewing. About 15% of 482 independently living 70-year-olds in Japan reported trouble with them, together with apples and grilled beef, linked to deeper gum pockets. In a randomized trial of new complete dentures, a soft silicone liner improved self-rated chewing of hard crackers only after 3 months. In 105 patients with swallowing problems, 92.4% ate a test cracker without aspiration on camera, so 7.6% did aspirate. That describes a test done under a camera, and does not show the cracker is safe for someone with swallowing problems.

Sources

1. rcrk-daily-r5-06 · food composition survey
   A wide range of rice products had total and inorganic arsenic levels that typified those found in rice grain including, crisped rice, puffed rice, rice crackers, rice noodles and a range of Japanese rice condiments as well as rice products targeted at the macrobiotic, vegan, lactose intolerant and gluten intolerance food market. Most As in rice products are inorganic As (75.2-90.1%).
   Environment International, 2009 · checked 2026-09-30
2. rcrk-daily-r5-11 · USDA SR Legacy dataset
   Rice crackers, SR Legacy FDC 173161: magnesium 156 MG, selenium 25.5 UG, thiamin 0.436 MG per 100 g
   USDA FoodData Central, SR Legacy 2018, FDC 173161 (Rice crackers) · checked 2026-09-30
3. rcrk-daily-r5-10 · USDA FNDDS dataset
   Crackers, rice, FNDDS code 54319000, fdc_id 2708163: 1 cracker 3 g; Quantity not specified 18 g; 1 cup, NFS 40 g; Sodium 233 MG per 100 g
   USDA FNDDS, food code 54319000 (FDC 2708163) · checked 2026-09-30
4. rcrk-daily-r5-03 · randomized controlled trial
   In trial 1, of ingestion of rice crackers, the incremental area under the curves of glucose (IAUCglc) and insulin (IAUCins) in RS group was significantly lower than in the control group.
   Bioscience, Biotechnology, and Biochemistry, 2020 · checked 2026-09-30
5. rcrk-daily-r5-01 · randomized controlled trial
   Lampang's Crispy Rice Cracker (68 g, high-GI group, n = 10), each consumed alongside their standard breakfast ... In the high-GI dessert group, the abundance of Collinsella and Bifidobacterium decreased compared to the low- and medium-GI groups, while Roseburia and Ruminococcus showed slight increases.
   Nutrients, 2024 · checked 2026-09-30
6. rcrk-daily-r5-02 · randomized controlled trial
   Healthy participants or those with T2DM consumed either buckwheat or rice crackers. Blood samples were collected at baseline and 15, 30, 45, 60, 120 and 180minutes after consumption. ... Interestingly, changes in these hormones did not lead to changes in post-prandial glucose, insulin or C-peptide concentrations.
   Metabolism, 2013 · checked 2026-09-30
7. rcrk-daily-r5-05 · cross-sectional
   In a nationally representative sample of the US civilian, noninstitutionalized population, fish (adults), rice (children), and rice cakes/crackers (adolescents) had the largest associations with urinary DMA. For MMA, rice beverage/milk (adults) and rice cakes/crackers (children, adolescents) had the largest associations.
   PLoS One, 2014 · checked 2026-09-30
8. rcrk-daily-r5-07 · case report
   In addition, 3 of 8 other kinds of processed rice crackers were contaminated by wheat protein, with levels ranging from 0.26 to 1.13 microg/g. CONCLUSIONS: Approximately 13.5 microg of wheat protein can elicit a systemic adverse reaction in highly sensitive, wheat allergic individuals.
   Ann Allergy Asthma Immunol, 2004 · checked 2026-09-30
9. rcrk-daily-r5-04 · randomized controlled trial
   It also took three months for the patient-reported masticatory ability to improve for cubic rice crackers, hard rice crackers, and dry squid and to show a difference between the RD and CD groups.
   J Prosthodont Res, 2022 · checked 2026-09-30
10. rcrk-daily-r5-08 · cross-sectional
    One hundred and five patients with dysphagia were included. ... 92.4% of the patients ate the rice cracker without aspiration.
    Arch Gerontol Geriatr, 2018 · checked 2026-09-30
11. rcrk-daily-r5-09 · cross-sectional
    Food acceptability was evaluated from the difficulty experienced in chewing apples, grilled beef, and hard rice crackers. ... Approximately 15% of participants were included in the compromised food acceptability group.
    J Oral Rehabil, 2014 · checked 2026-09-30
12. rcrk-daily-r5-12 · cross-sectional
    Satisfaction with masticatory function and food acceptability (apples, grilled beef, and hard rice crackers) were evaluated using questionnaires. ... Multiple logistic regression analysis showed that the number of foods that could be eaten without difficulty was the most important explanatory variable for dissatisfaction with masticatory function (P < .01).
    Int J Prosthodont, 2007 · checked 2026-09-30