Brown rice or whole wheat bread: closer than they look

We found no trial that put brown rice against whole wheat bread, so this comparison rests on what each food contains and on research into whole grains as a group. A meta-analysis of 37 randomized trials found whole grains lowered fasting blood glucose by 1.9 mg/dL (95% CI 0.5 to 3.2; metric: 0.103 mmol/L, 0.028 to 0.178), a small effect from whole grains in general. Per serving the two foods are close. A cup of cooked brown rice (195 g) gives 240 calories, 50 g of carbohydrate, 1.9 g of fiber and 4.7 g of protein. A regular 1.3 oz (36 g) slice of whole wheat bread gives 91 calories, 15.5 g of carbohydrate, 2.2 g of fiber and 4.4 g of protein, so one cup of rice carries the energy of about 2.6 slices. Weight for weight the bread is denser, with 6 g of fiber per 3.5 oz (100 g) against 1 g for cooked rice.

How much is actually in it

• A cup of cooked brown rice (195 g) gives about 240 calories, 50 g carbohydrate, 1.9 g fiber and 4.7 g protein in US survey coding. — USDA FNDDS food code 56205018, Rice, brown, cooked, no added fat (n = 1 food) Evidence E source
  Per 100 g: 123 calories, carbohydrate 25.76 g, fiber 1 g, protein 2.43 g, magnesium 39 mg, sodium 201 mg; per cup 195 g: 239.8 calories, 50.2 g, 1.9 g, 4.7 g, 76.0 mg, 391.9 mg
• A regular 1.3 oz (36 g) slice of whole wheat bread gives about 91 calories, 15.5 g carbohydrate, 2.2 g fiber, 4.4 g protein and 155 mg sodium. — USDA FNDDS food code 51300110, Bread, whole wheat (n = 1 food) Evidence E source
  Per 100 g: 254 calories, carbohydrate 43.1 g, fiber 6 g, protein 12.3 g, magnesium 77 mg, sodium 430 mg; per 36 g slice: 91.4 calories, 15.5 g, 2.2 g, 4.4 g, 27.7 mg, 154.8 mg

What a real portion looks like

• US survey coding counts a cup of cooked brown rice as 195 g and a regular slice of whole wheat bread as 36 g, so one cup equals the energy of about 2.6 slices. — USDA FNDDS portion measures (n = 2 foods) Evidence E source
  Brown rice: 1 cup 195 g, unspecified 147 g; whole wheat bread: thin 24 g, regular 36 g, thick 43 g

What your body absorbs

• In 14 healthy adults, instant brown rice had a high glycemic index of 87.8, while intact whole grain pilaf scored 58.9. — 14 healthy adults, mean age 25, 50 g available carbohydrate portions (n = 14) Evidence B source
  GI instant brown rice 87.8 +/- 6.8; whole grain pilaf 58.9 +/- 5.1 (P < 0.01)
• A systematic review found rice glycemic index ranging from 48 to 93, and the brown rice advantage over white shrinks at the longer cooking times brown rice needs. — original studies of postprandial glucose and insulin responses to rice Evidence C source
  GI 48 to 93; insulinemic index 39 to 95

What it does to your health

• Across 37 RCTs, whole grains lowered fasting blood glucose by 1.8 mg/dL (0.10 mmol/L), a small effect. — adults in 37 randomized trials and 10 prospective cohorts (n = 37 RCTs) Evidence A source
  FBG MD -1.9 mg/dL (-3.2 to -0.5; metric: -0.103 mmol/L, -0.178 to -0.028); HbA1c -0.06% (P = 0.05); cohorts RR 0.761 (0.700-0.828) per 50 g/day
• A network meta-analysis of 152 RCTs found adding whole grains changed body weight by only 0.97 lb (0.44 kg), a trivial effect on very low certainty evidence. — adults in 152 randomized trials of single foods or food groups (n = 9669) Evidence A source
  Whole grains MD -0.97 lb (-0.44 kg) (95% CrI -0.88 to 0.0), GRADE very low

Safety, limits and interactions

• A meta-analysis of 15 cooking studies found cooking lowers arsenic, lead and cadmium in rice, with rinsing and parboiling working best. — rice samples in 15 laboratory cooking studies (n = 15 studies) Evidence D source
  Arsenic WMD -0.04 mg/kg (-0.05 to -0.03); lead -0.01; cadmium -0.01
• FDA states that cooking rice like pasta, in excess water, removes 40 to 60 percent of its inorganic arsenic. — US consumers cooking rice Evidence E source
  40-60% less inorganic arsenic; enrichment nutrients in white and parboiled rice fall 50-70%

What people believe that the data does not support

• The EU did not authorize the claim that diets rich in whole grain foods promote heart health. — EU Register on nutrition and health claims Evidence E source
  Status Non-authorized

Who this works differently for

• In 31 adults with type 2 diabetes, two weeks of less-processed whole grains, including brown rice, cut post-meal glucose 6% versus the same grains finely milled. — adults with type 2 diabetes, 2-week crossover periods of nutrient-matched whole-grain wheat, oat and brown rice foods differing in milling (n = 31) Evidence B source
  Postprandial response -9% (3-15) after breakfast, -6% (1-10) over all meals; weight difference 1.8 lb (1.4 to 2.3; metric: 0.81 kg, 0.62 to 1.05)
• In 30 Malawian infants, iron absorption from fortified whole grain wheat cereals with pulses was 12.8 to 15.8%, similar to 12.1% from refined wheat. — 30 Malawian children aged 6-14 months, 70% anemic, 25 g cereal servings with ascorbic acid (n = 30) Evidence B source
  Fractional iron absorption: refined wheat 12.1%; WG wheat-lentil 15.8%; WG wheat-chickpea 12.8%; WG oat 9.2%

The bottom line

The studies we have looked at processing, not at rice against bread. In 14 healthy adults, instant brown rice had a glycemic index of 87.8, high by any table, while an intact whole grain pilaf scored 58.9. A systematic review found rice glycemic index ranging from 48 to 93, and at the longer cooking times brown rice needs, its difference from white rice became small and inconsistent. In 31 adults with type 2 diabetes, two weeks of less processed whole grains, brown rice among them, gave a 6% lower blood glucose response after all meals (95% CI 1 to 10) than the same grains finely milled. That result is for people with diabetes and for milling, not for rice against bread. Neither food will move your weight much. A network meta-analysis of 152 randomized trials found adding whole grains changed body weight by 0.97 lb (0.44 kg), which the authors called trivial, on very low certainty evidence. The EU refused the claim that diets rich in whole grain foods promote heart health, meaning the evidence did not meet its bar when assessed. The sodium figures depend on the kitchen. The survey value of 392 mg a cup for rice assumes it was cooked in salted water, and a regular slice of bread carries 155 mg, which varies by brand. Who should be careful. Rice takes up inorganic arsenic, and the FDA says cooking it like pasta, in plenty of water that is then drained, removes 40 to 60 percent of it depending on the type of rice. A meta-analysis of 15 laboratory cooking studies ranked rinsing first and parboiling second for lowering arsenic, lead and cadmium. Those are measurements on rice, and none separated brown rice out. We have no card on arsenic from rice in infants, young children or pregnancy, so the infant cereal study on this page, which tested wheat, says nothing about choosing brown rice for a baby. We have no card on arsenic in bread, and none on wheat allergy, celiac disease, pregnancy or medicines for either food, so this page cannot speak to them.

Sources

1. brww-r2-01 · composition dataset
   Rice, brown, cooked, no added fat, FNDDS code 56205018, fdc_id 2708414, per 100 g: Energy 123 kcal; Carbohydrate, by difference 25.76 g; Fiber, total dietary 1 g; Protein 2.43 g; Magnesium, Mg 39 mg; Sodium, Na 201 mg; 1 cup, cooked 195 g: 239.8 kcal; 50.2 g; 1.9 g; 4.7 g; 76.0 mg; 391.9 mg
   USDA FNDDS, food code 56205018, FDC 2708414 · checked 2026-10-02
2. brww-r2-02 · composition dataset
   Bread, whole wheat, FNDDS code 51300110, fdc_id 2707709, per 100 g: Energy 254 kcal; Carbohydrate, by difference 43.1 g; Fiber, total dietary 6 g; Protein 12.3 g; Magnesium, Mg 77 mg; Sodium, Na 430 mg; 1 medium or regular slice 36 g: 91.4 kcal; 15.5 g; 2.2 g; 4.4 g; 27.7 mg; 154.8 mg
   USDA FNDDS, food code 51300110, FDC 2707709 · checked 2026-10-02
3. brww-r2-03 · portion dataset
   Rice, brown, cooked, no added fat, fdc_id 2708414: 1 cup, cooked 195 g; Quantity not specified 147 g. Bread, whole wheat, fdc_id 2707709: 1 small or thin/very thin slice 24 g; 1 medium or regular slice 36 g; 1 large or thick slice 43 g
   USDA FNDDS, FDC 2708414 and 2707709 · checked 2026-10-02
4. brww-r2-05 · randomized trial
   The GI (mean ± standard error) of IBR was the highest (87.8 ± 6.8) followed by RMU (74.7 ± 6.5) and WMU (71.4 ± 5.1). WGP had medium GI (58.9 ± 5.1; P < 0.01 vs. IBR).
   J Food Sci, 2019 · checked 2026-10-02
5. brww-r2-06 · systematic review
   However, at longer cooking times normally used for the preparation of brown rice, smaller and inconsistent differences are observed between brown and white rice.
   Br J Nutr, 2015 · checked 2026-10-02
6. brww-r2-07 · meta-analysis of RCTs and cohorts
   In RCTs, whole grains significantly reduced fasting blood glucose (Mean difference (MD) = -0.103 mmol/L, 95% CI: -0.178 to -0.028; I2 = 72.99%, P < 0.01)
   Nutr J, 2024 · checked 2026-10-02
7. brww-r2-08 · network meta-analysis of RCTs
   Increased consumption of fish (MD - 0.85 kg, 95% CrI - 1.66, - 0.02; GRADE = low), whole grains (MD - 0.44 kg, 95% CrI - 0.88, 0.0; GRADE = very low), and nuts (MD - 0.37 kg, 95% CI - 0.72, - 0.01; GRADE = low) demonstrated trivial weight loss
   Eur J Nutr, 2023 · checked 2026-10-02
8. brww-r2-10 · meta-analysis of laboratory studies
   Furthermore, based on the subgroup analysis 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 2026-10-02
9. brww-r2-11 · agency position
   Published studies, including research by the FDA, show that cooking rice similar to how pasta is cooked can reduce 40 to 60 percent of the inorganic arsenic content, depending on the type of rice.
   US FDA, What You Can Do to Limit Exposure to Arsenic, 2022 · checked 2026-10-02
10. brww-r2-12 · regulatory register
    POL-HC-7014 Diet rich in whole grain diets rich in whole grain foods promote heart health Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-7014, snapshot 2026-09-21 · checked 2026-10-02
11. brww-r2-04 · randomized crossover trial
    Postprandial responses were 9% (95% CI 3-15) lower following breakfast and 6% (1-10) lower following all meals of less-processed whole grains when compared with finely milled grains.
    Diabetes Care, 2020 · checked 2026-10-02
12. brww-r2-09 · randomized crossover trial
    Geometric mean FIA percentages (-SD, +SD) from the cereals were as follows: 1) refined wheat, 12.1 (4.8, 30.6); 2) WG-wheat-lentil, 15.8 (6.6, 37.6); 3) WG-wheat-chickpeas, 12.8 (5.5, 29.8); and 4) WG-oat, 9.2 (3.9, 21.5) and 7.4 (2.9, 18.9) from WG-oat-FeBG.
    J Nutr, 2022 · checked 2026-10-02