Wild rice: a grain with almost no evidence of its own

Wild rice comes from a different plant than rice, and almost none of the research is about wild rice itself. The strongest number on this page belongs to whole grains as a class. Across 32 randomized trials in 2060 adults, eating whole grains lowered fasting glucose by 0.9 mg/dL (0.05 mmol/L) (95% CI 0.01 to 0.10 lower) and showed no significant change in fasting insulin, HbA1c, HOMA-IR or two-hour glucose. Wild rice belongs to that class by composition, so read the figure as context rather than as an effect of the grain, and notice how small it is either way. Tested more directly, in a randomized crossover in 14 healthy adults in Great Britain, a basmati and wild rice blend landed outside the low glycemic index group in a set of ten rice foods that spanned values of 37 to 92. Wild rice on its own was never tested there, and the published abstract gives the blend a category instead of a number.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• Copper in dry raw wild rice averages 0.487 mg per 3.5 oz (100 g) but ranges from 0.086 to 0.808 mg across 8 Foundation samples, a spread of 148 percent. — 8 Foundation Foods samples of Wild rice, dry, raw (FDC 2710821) (n = 8) Evidence E source
  Median 0.5315 mg/100 g, range 0.0863 to 0.808 mg/100 g, spread 148%
• Two national food tables disagree on wild rice zinc by about a quarter: USDA gives 5.845 mg per 3.5 oz (100 g) for dry raw grain and UK CoFID gives 4.3 mg per 3.5 oz (100 g). — reference entries for raw wild rice in two national composition tables (n = 2 dataset entries) Evidence E source
  USDA 5.845 vs CoFID 4.3 mg/100 g, difference 26%; niacin 6.914 vs 4.4 mg/100 g, difference 36%
• Laboratory analysis of three wild rice cultivars found calcium about 4.3 times higher than in brown rice and about 9.4 times higher than in white rice. — whole grain, milled grain and bran fractions of three Zizania palustris cultivars compared with white and brown rice, three replicates each (n = 3 cultivars, n = 3 replicates) Evidence D source
  Total mineral content 897.80 mg/100 g in wild rice vs 269.83 mg/100 g white rice and 310.78 mg/100 g brown rice; calcium 4.3-fold over brown rice and 9.4-fold over white rice

What a real portion looks like

• One cup of cooked 100 percent wild rice weighs 5.8 oz (164 g) in the US food survey coding, whether or not fat is added. — US dietary survey portion coding for cooked wild rice (n = 2 dataset entries) Evidence E source
  1 cup cooked = 164 g; unspecified quantity = 123 g

What your body absorbs

• In a simulated digestion of three commercial wild rice brands only 14 to 23 percent of total phenolics became bioaccessible, and antioxidant activity even less. — three commercial Zizania palustris brands bought in Manitoba in June 2025, cooked and put through simulated oral, gastric and intestinal digestion (n = 3 brands) Evidence D source
  Total phenolics bioaccessibility 14 to 23 percent; DPPH below 6 percent, ABTS below 10 percent; ferulic acid insolubility above 97 percent

What cooking and storage change

• Milling wild rice strips moisture, ash and protein and raises starch, yet milled wild rice still holds 8.69 to 9.99 g protein per 3.5 oz (100 g) against 7.03 g in milled brown rice. — whole grain versus milled grain fractions of three Zizania palustris cultivars, three replicates each (n = 3 cultivars, n = 3 replicates) Evidence D source
  Milled wild rice protein 8.69 to 9.99 g/100 g vs milled brown rice 7.03 g/100 g
• Cooking cut the free phenolic fraction of wild rice in every brand tested, for example from 17.27 to 11.95 mg GAE per g in one of them. — three commercial Zizania palustris brands, raw versus cooked at a 1 to 3 grain to water ratio until full gelatinisation (n = 3 brands) Evidence D source
  Free phenolics 17.27 mg GAE/g raw to 11.95 mg GAE/g cooked in brand EG, same direction in the other two

What it does to your health

• In a randomized crossover trial in 14 healthy adults the ten rice foods tested spanned glycemic index values of 37 to 92, and the basmati and wild rice blend was not among the low glycemic index foods. — 14 healthy adults in Great Britain, 6 men and 8 women, mean age 38 years, single test meals of 50 g available carbohydrate against a glucose standard (n = 14) Evidence B source
  GI range 37 to 92 across 10 foods; basmati and wild rice classified medium or high GI, not low
• Across 32 randomized trials in 2060 people, eating whole grains lowered fasting glucose by 0.9 mg/dL (0.05 mmol/L) (95% CI 0.01 to 0.10 lower) and showed no significant change in fasting insulin, HbA1c or HOMA-IR. — 2060 adults in 32 randomized controlled trials of whole grain intake, 3 to 16 weeks, median 8 weeks (n = 2060) Evidence A source
  Fasting glucose WMD -0.9 mg/dL (95% CI -1.8 to -0.18; metric: -0.05 mmol/L, -0.10 to -0.01); fasting insulin, HbA1c, HOMA-IR and 2-h glucose not significant

Safety, limits and interactions

• A Chinese food safety evaluation reported very low arsenic, cadmium and lead in wild rice grain and no ill effects among 110 people over 60 years old who ate it habitually. — 110 habitual eaters of Chinese wild rice aged over 60 years, plus acute toxicity, micronucleus, sperm abnormality and Salmonella mutagenicity tests in mice (n = 110) Evidence C source
  No ill effects reported; heavy metal levels described as very low; all animal genotoxicity tests negative

What people believe that the data does not support

• The EU register holds no claim for wild rice as a food, and the blood lipid claim for its niacin was refused, while six niacin claims covering energy metabolism and tiredness are authorized. — EU Register on nutrition and health claims, snapshot of 21 September 2026, 2330 claims (n = 9 niacin entries) Evidence E source
  Niacin 6 authorized and 3 non-authorized; zinc 18 authorized and 16 non-authorized; zero entries under the name wild rice in the EU register and in 21 CFR 101

Who this works differently for

• In a cross-sectional survey of 186916 adults, brown and wild rice was the second largest whole grain source for Native Hawaiian men and Japanese Americans, while whole wheat or rye bread led in every other group. — 186916 adults aged 45 to 75 years in Hawaii and Los Angeles County from five ethnic groups, food frequency questionnaire collected 1993 to 1996 (n = 186916) Evidence C source
  Brown/wild rice ranked second among whole grain sources in two ethnic-sex groups; grain foods supplied 27.1 to 35.8 percent of niacin intake
• Among 319 older adults who picked the same portion size on a questionnaire, men still reported eating more brown and wild rice than women in their 24-hour recalls. — 319 members of the Hawaii-Los Angeles Multiethnic Cohort aged 56 to 80 years, three telephone 24-hour recalls plus a food frequency questionnaire, 2010 to 2011 (n = 319) Evidence C source
  Portions significantly higher in men than women for brown/wild rice and seven other items, adjusted for race and ethnicity

What is still unknown

• The authors of the only bioaccessibility study on wild rice state that their in vitro model cannot say what happens in the body, and that dynamic or in vivo digestion work is still missing. — authors of the 2026 in vitro digestion study on three commercial wild rice brands Evidence D source
  No in vivo absorption, metabolism or health outcome measured for wild rice phenolics

The bottom line

A cup of cooked wild rice is 164 g in US survey coding, which is a coding convention rather than a weighed plate. Composition is the honest reason to buy it, and the label is approximate. Copper in dry raw grain averaged 0.487 mg per 3.5 oz (100 g) across eight USDA Foundation samples but ran from 0.086 to 0.808 mg, a spread of 148 percent, so no single copper figure for wild rice is trustworthy. The US and UK tables, paired by product name rather than by proven identity, disagree by 26 percent on zinc, 5.845 against 4.3 mg per 3.5 oz (100 g), and by 36 percent on niacin. Laboratory analysis of three cultivars found calcium about 4.3 times higher than in brown rice and 9.4 times higher than in white rice, which is three cultivars on a bench and not a survey of the shelf. Milling in that same work left 8.69 to 9.99 g protein per 3.5 oz (100 g) against 7.03 g in milled brown rice. Cooking cut the free phenolic fraction in all three commercial brands tested, from 17.27 to 11.95 mg GAE per g in one of them. Separate work on Zizania aquatica found no such loss, so treat boiling losses as an open disagreement. In a simulated digestion of those same brands only 14 to 23 percent of total phenolics became bioaccessible, and the authors state that their laboratory model cannot say what happens inside a person. On safety there is effectively nothing for the grain sold in the West. The single study reported no ill effects among 110 habitual eaters over 60 years old, but it dates from 1996, it ran without a control group or quantitative thresholds, and it was done on Zizania latifolia, a different species from the Zizania palustris sold here as wild rice. We found no trial on allergy, pregnancy, children or drug interactions for wild rice at all. The EU register holds no claim under the name wild rice, and the blood lipid claim for its niacin was refused, while six niacin claims about energy metabolism and tiredness stand.

Compared with other foods

Sources

1. wldrc-daily-r3-01 · food composition dataset
   Wild rice, dry, raw Copper, Cu 0.487 MG range 0.0863–0.808 (median 0.5315), samples 8, spread 148%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 · checked 2026-09-25
2. wldrc-daily-r3-02 · food composition datasets
   zinc USDA 5.845 / CoFID 4.3 mg difference 26% ← DISCREPANCY
   USDA FoodData Central Foundation Foods 2026-04-30 (FDC 2710821) and CoFID 2021, Public Health England, OGL v3.0 (code 11-872) · checked 2026-09-25
3. wldrc-daily-r3-03 · laboratory grain analysis
   Compared with rice controls, ZP contained significantly higher levels of both macroelements and trace elements among all samples. ... Additionally, the calcium (Ca) content in ZP was approximately 4.3- and 9.4-fold higher than in BR and WR, respectively.
   Food Chemistry: X, 2026 · checked 2026-09-25
4. wldrc-daily-r3-09 · dietary survey portion dataset
   Rice, wild, 100%, cooked, fat added / 1 cup, cooked · 10043 164
   USDA FNDDS, food code 56205215 and 56205210 (FDC 2708425, 2708424) · checked 2026-09-25
5. wldrc-daily-r3-05 · in vitro digestion
   It is important to note that, despite some increase in phenolic release during intestinal digestion, the overall bioaccessibility of total phenolics (14–23%) and antioxidant activity (DPPH < 6%, ABTS < 10%) remained relatively low.
   Molecules, 2026 · checked 2026-09-25
6. wldrc-daily-r3-04 · laboratory milling experiment
   Compared to the whole grains, the milled grains exhibited a decrease in moisture, ash, and protein, while total starch increased due to the removal of the bran. ... Notably, the protein content in milled ZP (MG-ZP, 8.69–9.99 g/100 g) remained significantly higher than in milled BR (7.03 g/100 g), indicating that the inherent nutritional advantage of ZP is partially preserved even after milling.
   Food Chemistry: X, 2026 · checked 2026-09-25
7. wldrc-daily-r3-06 · laboratory cooking experiment
   Cooking significantly reduced TPC in the free phenolic fraction for all varieties. For instance, EG decreased from 17.27 mg GAE/g (raw) to 11.95 mg GAE/g (cooked), with similar patterns observed in SY and FL.
   Molecules, 2026 · checked 2026-09-25
8. wldrc-daily-r3-07 · randomized crossover trial
   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 2026-09-25
9. wldrc-daily-r3-08 · meta-analysis of RCTs
   In total, 2,060 participants were included in the 32 included studies (18 parallel design and 14 cross‐over design studies), and the number of participants in each study ranged from 11 to 206. ... As shown in Figure 2 and Table S3, a significant reduction in fasting glucose concentration was observed in participants supplemented with whole grain (WMD −0.05 mmol/L, 95% CI −0.10, −0.01 mmol/L) when compared with control participants.
   Journal of Diabetes Investigation, 2022 · checked 2026-09-25
10. wldrc-daily-r3-12 · food safety evaluation
    Levels of non-nutritive mineral elements such as arsenic, cadmium and lead are very low. The eating patterns of 110 people ( > 60 yr) showed no ill-effects.
    Food Chem Toxicol, 1996 · checked 2026-09-25
11. wldrc-daily-r3-13 · regulatory register
    POL-HC-8361 Niacin (nicotinic acid) Niacin (nicotinic acid) may help to control blood lipid profiles/cholesterol/ triglycerides Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-8361, snapshot 2026-09-21 · checked 2026-09-25
12. wldrc-daily-r3-10 · cross-sectional cohort analysis
    The top source of whole grains was whole wheat/rye bread for all ethnic-sex groups, followed by popcorn and cooked cereals, except for Native Hawaiian men and Japanese Americans, for whom brown/wild rice was the second top source ... Grain foods made an important contribution to the intakes of thiamin (30.2-45.9%), riboflavin (23.1-29.2%), niacin (27.1-35.8%), vitamin B6 (22.9-27.5%), and folic acid (23.3-27.7%).
    Nutr J, 2013 · checked 2026-09-25
13. wldrc-daily-r3-11 · cross-sectional calibration study
    Participants (n=319) were members of the Hawaii-Los Angeles Multiethnic Cohort who completed three 24HDRs and a QFFQ in a calibration study conducted in 2010 and 2011. ... Although they chose the same portion size on the QFFQ, mean intake amounts from 24HDRs were significantly higher for men than for women for "beef/lamb/veal," "white rice," "brown/wild rice," "lettuce/tossed salad," "eggs cooked/raw," "whole wheat/rye bread," "buns/rolls," and "mayonnaise in sandwiches."
    J Acad Nutr Diet, 2018 · checked 2026-09-25
14. wldrc-daily-r3-14 · in vitro digestion
    While this study provides insight into compositional changes and potential phenolic release during digestion, the physiological implications of these results cannot be determined from the present in vitro model. ... Further research, including studies on food structure, matrix interactions, and dynamic or in vivo digestion systems, is necessary to elucidate the mechanisms of phenolic release and their potential impact on human health.
    Molecules, 2026 · checked 2026-09-25