Rice and wild rice: what swapping the grain changes, and what it leaves alone

A meta-analysis of randomized trials found that intact whole-grain rice lowered the blood glucose area under the curve by 730 mg/dL (40.5 mmol/L)·min compared with white rice (95% CI 21.3 to 59.6 lower). Those were short after-meal tests, and wild rice was not analyzed on its own. Longer-term markers tell a different story. In 7 trials with 417 adults with prediabetes or type 2 diabetes, brown rice in place of white did not change HbA1c or fasting glucose, and body weight fell by 4.9 lb (95% CI 2.8 to 6.9; metric: 2.2 kg, 1.26 to 3.13). Wild rice stands out in its composition. Per 100 g dry and raw it carries 5.8 mg of zinc against 1.4 mg in unenriched white long grain rice, averaged over 8 samples of each. Whether it is any easier on blood sugar is still open. The one trial that included it, in 14 healthy adults, tested a basmati and wild rice mix, and the mix did not come out as low glycemic index.

How much is actually in it

• Dry raw wild rice carries about 4 times the zinc of raw unenriched white long grain rice, 5.845 versus 1.354 mg per 3.5 oz (100 g) as averaged over 8 samples each. — Foundation Foods samples, 8 per product (n = 16) Evidence E source
  Zn 5.845 mg/100 g (range 4.33 to 6.96) vs 1.354 mg/100 g (range 0.804 to 1.79)
• How much fiber white rice holds depends on the lab method: the older total dietary fiber assay gives 0.15 g per 3.5 oz (100 g) raw white rice, the newer AOAC 2011 assay 2.77 g, while wild rice measures 4.26 g. — Foundation Foods samples, 8 per product (n = 16) Evidence E source
  White rice 0.149 g (range 0 to 1.19) vs 2.771 g (range 2.1 to 3.56) by method, wild rice 4.26 g (range 3.56 to 4.98)

What a real portion looks like

• In US survey coding one cup of cooked plain white rice weighs 5.6 oz (158 g) and one cup of cooked 100 percent wild rice 164 g. — US dietary survey portion coding for cooked rice Evidence E source
  1 cup cooked: 158 g white (56205008) vs 164 g wild (56205210)

What your body absorbs

• A meta-analysis of randomized trials found intact whole-grain rice cut the blood glucose area under the curve by 730 mg/dL (40.5 mmol/L)·min compared with white rice. — randomized controlled trials, 14 strata on whole-grain rice (n = 14 strata) Evidence A source
  -40.5 mmol/L·min (95% CI -59.6 to -21.3)
• In a randomized crossover trial in 12 healthy women, drinking green tea with 150 g white rice raised the blood glucose response by speeding gastric emptying. — 12 healthy females (n = 12) Evidence B source
  Significantly higher postprandial glucose with liquid, size not given in abstract

What cooking and storage change

• Per the USDA table for white or brown rice cooked and drained, about 60 percent of folate, 75 percent of thiamin and 90 percent of iron are retained. — Cereal grains group, rice white/brown, cooked, drained Evidence E source
  Retention folate 60%, thiamin 75%, iron 90%, zinc 95%
• Pooling 15 studies, cooking lowered arsenic, lead and cadmium in rice by a pooled 0.04 mg/kg, and rinsing ranked as the most effective method ahead of parboiling. — fifteen studies (n = 15 studies) Evidence D source
  WMD -0.04 mg/kg (95% CI -0.05 to -0.03)

What it does to your health

• In 7 trials with 417 adults with prediabetes or type 2 diabetes, swapping white for brown rice did not change HbA1c or fasting glucose but lowered body weight by 4.9 lb (2.2 kg). — 417 adults with prediabetes or type 2 diabetes (n = 417) Evidence B source
  HbA1c p = 0.15, FBG p = 0.95, weight MD -4.9 lb (95% CI -6.9 to -2.8; metric: -2.2 kg, -3.13 to -1.26)
• Cohort data link the highest white rice intake to 55 percent higher type 2 diabetes risk in Asian populations but show no clear link in Western populations. — 352,384 participants (n = 352384) Evidence C source
  RR 1.55 (95% CI 1.20 to 2.01) Asian vs RR 1.12 (0.94 to 1.33) Western
• In a randomized crossover trial in 14 healthy adults, rice products ranged from glycemic index 37 to 92 and a basmati and wild rice mix did not test as low glycemic index. — Fourteen healthy subjects (n = 14) Evidence B source
  GI range 37 to 92, basmati and wild rice in medium or high GI group
• In a randomized crossover trial in 15 overweight Asian Indians, 5 days of brown rice instead of white rice lowered the daily glucose response by 19.8 percent. — Fifteen overweight Asian Indians without diabetes (n = 15) Evidence B source
  5-day average IAUC 19.8% lower (P=0.004)

Safety, limits and interactions

• FDA set an action level of 100 ppb inorganic arsenic for infant rice cereals in its 2020 final guidance to reduce infant exposure. — infants Evidence E source
  Action level 100 mcg/kg (100 ppb) inorganic arsenic
• Across 580 baby foods tested worldwide, rice mixes had a median arsenic level of 0.048 mg/kg and 30 percent of them exceeded the international maximum level. — 580 baby foods and 251 infant formulas (n = 580) Evidence C source
  As median 0.048 mg/kg in rice mixes, 30% above ML

What people believe that the data does not support

• The EU refused a claim that germinated brown rice helps maintain normal blood glucose, and its register holds no claim at all for wild rice. — EU claim register Evidence E source
  Non-authorized

Who this works differently for

• Pooled cohorts link high rice intake to 40 percent higher risk of chronic disease in women but not in men. — twelve studies (n = 12 studies) Evidence C source
  RR 1.40 (95% CI 1.13 to 1.73) women vs 0.95 (0.72 to 1.24) men

What is still unknown

• No USDA retention factor covers wild rice, so how cooking changes its vitamins and minerals is not known from the standard tables. — USDA retention table, cereal grains group Evidence E source
  No wild rice row among 14 methods of the group

The bottom line

The fiber number for white rice depends on the lab method. The older assay gives 0.15 g per 3.5 oz (100 g) raw, the newer AOAC 2011 assay 2.77 g. Wild rice has only the older figure, 4.26 g. A cup of cooked plain white rice weighs 5.6 oz (158 g) in US survey coding, and a cup of cooked wild rice 164 g. Cohort data link the highest white rice intake to 55 percent higher risk of type 2 diabetes in Asian populations (RR 1.55, 95% CI 1.20 to 2.01), where people ate three to four servings a day. In Western populations, eating one or two servings a week, there was no clear link (RR 1.12, 0.94 to 1.33). That is an association, and it does not show that rice caused the cases. A separate pool of twelve cohort studies links high rice intake to 40 percent higher risk of chronic disease in women (RR 1.40, 1.13 to 1.73) and finds none in men, with large differences between the studies. In 15 overweight Asian Indians, five days of brown rice instead of white cut the daily glucose response by 19.8 percent. In 12 healthy women, drinking green tea with 5.3 oz (150 g) of white rice raised the glucose response by speeding up stomach emptying, and the abstract gives no size. Cooking white or brown rice and draining it keeps about 60 percent of the folate, 75 percent of the thiamin and 90 percent of the iron, by the USDA retention table. No such factor exists for wild rice. Pooling 15 laboratory studies of the grain, cooking lowered arsenic, lead and cadmium together by a pooled 0.04 mg/kg (95% CI 0.03 to 0.05), and rinsing ranked as the most effective method ahead of parboiling. Those are measurements in rice, not in people. The real caution here is for infants. In 2020 FDA set a non-binding action level of 100 ppb inorganic arsenic for infant rice cereals. Across 580 baby foods tested worldwide, rice mixes had a median arsenic level of 0.048 mg/kg, and 30 percent were above the international maximum, which describes the foods and says nothing yet about the children's health. The EU refused a claim that germinated brown rice helps keep blood glucose normal, and its register holds no claim of any kind for wild rice.

Sources

1. rcwr-r7-01 · Food composition data
   Wild rice, dry, raw Zinc, Zn 5.845 MG range 4.33–6.96 (median 5.98), samples 8, spread 45% / Rice, white, long grain, unenriched, raw Zinc, Zn 1.354 MG range 0.804–1.79 (median 1.41), samples 8, spread 73%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 (Wild rice, dry, raw; Rice, white, long grain, unenriched, raw) · checked 2026-10-03
2. rcwr-r7-02 · Food composition data
   Rice, white, long grain, unenriched, raw Fiber, total dietary 0.1488 G range 0.0–1.19 (median 0.0), samples 8, spread 800% / Rice, white, long grain, unenriched, raw Total dietary fiber (A 2.771 G range 2.1–3.56 (median 2.78), samples 8, spread 53% / Wild rice, dry, raw Fiber, total dietary 4.26 G range 3.56–4.98 (median 4.29), samples 8, spread 33%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 · checked 2026-10-03
3. rcwr-r7-05 · dietary survey portion dataset
   Rice, white, cooked, no added fat / 1 cup, cooked · 10043 158 · Rice, wild, 100%, cooked, no added fat / 1 cup, cooked · 10043 164
   USDA FNDDS (WWEIA), codes 56205008 and 56205210 · checked 2026-10-03
4. rcwr-r7-06 · Meta-analysis of RCTs
   Twenty publications were included, with 10, 14, and 5 strata (or active-control comparisons) on whole-grain wheat, rice, and rye, respectively. ... The consumption of intact (whole-grain) rice, compared with white rice, was associated with a significant reduction in blood glucose AUC (-40.5 mmol/L ⋅ min; 95% CI: -59.6, -21.3 mmol/L ⋅ min; P < 0.001).
   Am J Clin Nutr, 2018 · checked 2026-10-03
5. rcwr-r7-13 · RCT, crossover
   We performed a randomized crossover study in 12 healthy females. Three types of test meal were prepared: 150 g white rice (rice), 150 g white rice served alongside 200 mL of green tea (rice + tea), and 150 g white rice with 100 mL green tea poured over and served alongside 100 mL green tea (blend). ... Our findings demonstrated that compared with eating rice only, drinking liquid when eating rice causes an increase in postprandial blood glucose levels due to accelerated gastric emptying.
   Physiol Behav, 2025 · checked 2026-10-03
6. rcwr-r7-03 · Retention factor data
   RICE,WHITE/BROWN,COOKED,DRAINED · Retn_Code 431 · folate_total_ug 60% · thiamin_mg 75% · iron_mg 90% · zinc_mg 95%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), code 431 · checked 2026-10-03
7. rcwr-r7-04 · Meta-analysis of laboratory measurements
   Based on the inclusion and exclusion criteria, fifteen studies were selected as eligible for the meta-analysis. Our results showed a significant decrease in the content of arsenic, lead, and cadmium following the cooking rice (WMD= -0.04 mg/kg, 95% CI: -0.05, -0.03, P = 0.000) ... the overall rank order of cooking methods in the rice was rinsed > parboiling > Kateh > high-pressure, microwave, and steaming.
   Int J Environ Health Res, 2024 · checked 2026-10-03
8. rcwr-r7-07 · Meta-analysis of RCTs and CCTs
   Seven trials involving 417 adults with prediabetes or type 2 diabetes were included in this study. Brown-rice diet did not improve the glycemic control because it had no effect on the HbA1c level (p = 0.15) and the FBG level (p = 0.95) compared to white-rice diet. Brown-rice diet reduced body weight (p < 0.00001; MD -2.2 kg; 95% CI [-3.13 to -1.26]; I 2 = 0%).
   PeerJ, 2021 · checked 2026-10-03
9. rcwr-r7-08 · Meta-analysis of cohorts
   A total of 13,284 incident cases of type 2 diabetes were ascertained among 352,384 participants with follow-up periods ranging from 4 to 22 years. ... The pooled relative risk was 1.55 (95% confidence interval 1.20 to 2.01) comparing the highest with the lowest category of white rice intake in Asian populations, whereas the corresponding relative risk was 1.12 (0.94 to 1.33) in Western populations (P for interaction=0.038).
   BMJ, 2012 · checked 2026-10-03
10. rcwr-r7-09 · RCT, crossover
    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, whilst all of the other foods were medium-GI and high-GI foods.
    Int J Food Sci Nutr, 2009 · checked 2026-10-03
11. rcwr-r7-14 · RCT, crossover
    Fifteen overweight (body mass index, ≥23 kg/m(2)) Asian Indians without diabetes who were 25-45 years old participated in a randomized crossover study. ... The percentage difference in 5-day average IAUC was 19.8% lower in the BR group than in the WR group (P=0.004).
    Diabetes Technol Ther, 2014 · checked 2026-10-03
12. rcwr-r7-10 · Regulatory guidance
    The guidance identifies an action level of 100 micrograms per kilogram (µg/kg) or 100 parts per billion (ppb) which protects public health by reducing infants' dietary exposure to inorganic arsenic and is achievable by industry.
    US FDA, Guidance for Industry: Inorganic Arsenic in Rice Cereals for Infants: Action Level, 2020 · checked 2026-10-03
13. rcwr-r7-11 · Scoping review
    Seventy-five studies were included in the scoping review, which in total examined 580 baby foods and 251 infant formulas. ... For As, the highest median was found in mixed fish (0.165 mg/kg) and rice mixes (0.048 mg/kg), with 89% and 30% of items exceeding the As ML, respectively.
    Nutr Rev, 2026 · checked 2026-10-03
14. rcwr-r7-12 · Regulatory decision
    POL-HC-8510 Vibigaba (germinated brown rice) Contributes to the maintenance of normal blood glucose levels. -/- Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-8510, snapshot 2026-09-21 · checked 2026-10-03
15. rcwr-r7-16 · Meta-analysis of cohorts
    In a meta-analysis on seventeen risk estimates for highest v. lowest category of rice intake, provided from twelve studies, we found a trend towards a positive association (RR; 95 % CI) between rice consumption and risk of all chronic diseases (1·11; 0·96, 1·29) ... Stratified analysis by gender showed a significant positive association between rice consumption and risk of chronic diseases in women (1·40; 1·13, 1·73), but not in men (0·95; 0·72, 1·24).
    Public Health Nutr, 2017 · checked 2026-10-03
16. rcwr-r7-15 · Retention factor data
    GROUP EXISTS, NUTRIENTS EXIST, BUT «WILD RICE» IS NOT IN THIS GROUP.
    USDA Table of Nutrient Retention Factors, Release 6 (2007), Cereal Grains and Pasta group · checked 2026-10-03