Dal: strong evidence on blood glucose, weak iron

Dal is one of the few everyday dishes whose main ingredient has a meta-analysis behind it. Across 41 randomised trials, in the 11 where pulses were eaten on their own, fasting blood glucose fell by a standardised 0.82 units (95% CI -1.36 to -0.27), with variation between trials that was high and mostly unexplained. The pooled effect also changed with pulse type, dose and how the pulse was physically prepared, which is what cooking a pulse into dal does to it. A second pooling, of 9 acute feeding trials against control meals matched for calories, left people 31 percent fuller (ratio of means 1.31, 95% CI 1.09 to 1.58) on small samples and narrow participant groups. Those same people ate the same amount at the next meal (mean difference -19.94, 95% CI -75 to 35). Fullness moved and later intake did not. Iron is the weak spot. In 19 non-pregnant women, 6 of them anaemic, a 330 g lentil dal gave up 2.20 percent of its iron, against 23.6 percent from the same iron dose swallowed as ferrous sulfate, measured with iron labelled inside the lentils as they grew. Most of these trials fed pulses in general, and the ones that fed dal itself are small.

How much is actually in it

• Measured in people, a 98.5 g serving of lentils delivered 119 kcal, which is 16.0% less than the Atwater factors on a label predict. — 18 adults on a controlled diet with 7-day stool and urine collection after a 10-day adaptation (n = 18) Evidence B source
  Lentils 498 plus or minus 17 kJ per serving, 16.0% below Atwater General, P below 0.0001; chickpeas 10.4% below, P = 0.002

What your body absorbs

• Women absorbed 2.20% of the iron from a 330 g lentil dal against 23.6% from the same iron dose as ferrous sulfate, a ten-fold gap measured with labelled iron. — 19 non-pregnant women, 6 of them anaemic, each eating both test meals on consecutive days (n = 19) Evidence B source
  Iron absorption 2.20% plus or minus 3.40% from dal against 23.6% plus or minus 13.2% from ferrous sulfate, P below 0.001

What it does to your health

• Pulses eaten on their own lowered fasting blood glucose by a standardised 0.82 units (95% CI 0.27 to 1.36 units lower) pooled from 11 randomised trials inside a review of 41. — adults with and without diabetes in 41 randomised controlled trials lasting at least 7 days (n = 41 trials) Evidence A source
  Fasting blood glucose SMD -0.82, 95% CI -1.36 to -0.27; insulin SMD -0.49, 95% CI -0.93 to -0.04; glycated proteins -0.28 in low-GI diets
• A meal of pulses left people 31% fuller over the following hours (ratio of means 1.31, 95% CI 1.09 to 1.58), yet they ate the same amount at the next meal, pooled from 9 trials. — adults in 9 acute controlled feeding trials against isocaloric control meals (n = 9 trials) Evidence A source
  Satiety area under the curve 31% greater, RoM 1.31, 95% CI 1.09 to 1.58, P = 0.004; second meal intake unchanged, MD -19.94, 95% CI -75 to 35
• Chana dal carrying 50 g of carbohydrate cut the peak rise in blood glucose by 82.1% against glucose, where wheat cut it by 25% and rice by 16%. — 6 healthy adults, each tested after 50 g of carbohydrate as wheat, rice, chana dal, kidney beans or dextrose (n = 6) Evidence B source
  Peak plasma glucose rise lower by 82.1% for chana dal, 67% for kidney beans, 25% for wheat and 16% for rice, against dextrose

Safety, limits and interactions

• Eating 300 or 600 g of cooked lentils five times a week for 8 weeks lowered insulin resistance dose by dose in 30 at-risk adults, and 87.4% reported no or mild gut symptoms. — 30 non-diabetic adults with raised waist circumference, 5 prepared midday meals a week for 8 weeks (n = 30) Evidence B source
  HOMA-IR +1.2 units on control, -0.9 units at 300 g, P = .03, and -1.5 units at 600 g, P < .01; 87.4% reported no to mild gastrointestinal symptoms

Who this works differently for

• Adding a vitamin C-rich guava to mungbean dal for 7 months raised haemoglobin by 3.7 g/L more than dal alone and left 51% less anaemia in 200 Indian schoolchildren, while iron stores did not move. — 200 rural Indian children aged 6 to 10 years, 46% anaemic and 71% iron deficient at the start, fed daily on school days for 7 months (n = 200) Evidence B source
  Haemoglobin +3.7 g/L, 95% CI 1.6 to 5.6, P = 0.001; anaemia prevalence -51%, 95% CI -74 to -10, P = 0.022; body iron stores 0.65 mg/kg, 95% CI -0.34 to 1.63, P = 0.197

The bottom line

We have no USDA composition record for dal in this cohort, so the measured numbers here come from feeding studies instead. In 18 adults on a controlled diet, with seven days of stool and urine collected after a ten-day adaptation, a 98.5 g serving of lentils delivered 119 kcal, 16.0 percent below what the Atwater factors behind a label predict (P below 0.0001). Chickpeas came in 10.4 percent below (P = 0.002). Chana dal has the steepest single result on the page. Six healthy adults tested in 1981 after 50 g of carbohydrate showed a peak rise in blood glucose 82.1 percent lower than after dextrose, against 25 percent for wheat and 16 percent for rice. With six people and a single meal each, the ranking holds up better than the exact percentages, and nothing since has repeated it with chana dal. In 30 non-diabetic adults with a raised waist circumference eating five prepared midday meals a week for 8 weeks, 300 g of cooked lentils moved HOMA-IR by -0.9 units and 600 g by -1.5 units, against +1.2 on the control diet. Thirty people and eight weeks make that a signal rather than a settled number. Children are the one group studied apart from adults. Two hundred rural Indian children aged 6 to 10, 46 percent of them anaemic at the start, ate mungbean dal daily on school days for 7 months, some of them with a vitamin C-rich guava alongside. Measured against the children who ate the dal alone, the guava group gained 3.7 g/L more haemoglobin (95% CI 1.6 to 5.6) and ended with 51 percent less anaemia, while body iron stores did not move (0.65 mg/kg, 95% CI -0.34 to 1.63, P = 0.197). The guava pushed the vitamin C to iron ratio from about 0.5 to 1 up to about 18 to 1, far more vitamin C than a squeeze of lemon. On safety the page holds one finding. In that 8-week lentil trial, 87.4 percent of participants reported no gut symptoms or mild ones. We found no trial here on allergy, on pregnancy, on children under six or on any interaction with a medicine, so this page cannot tell you about those.

Sources

1. dal-r2-06 · randomised crossover trial
   The metabolizable energy of the lentils is 498 ± 17 kJ/serving (119 ± 4 kcal/serving) (serving mass = 98.5 g), which is 16.0% lower (p < 0.0001) and 13.6% lower (p = 0.003) than the ME calculated using Atwater General or Specific Factors, respectively.
   Nutrients, 2025 · checked 2026-09-24
2. dal-r2-03 · randomised crossover trial
   We found that the mean iron absorption from the dal was 2.20% ± 3.40% and was significantly lower than the 23.6% ± 13.2% observed from the same iron load given as ferrous sulfate (P < 0.001).
   J Nutr, 2015 · checked 2026-09-24
3. dal-r2-01 · meta-analysis of RCTs
   A total of 41 trials (39 reports) were included. Pulses alone (11 trials) lowered fasting blood glucose (FBG) (-0.82, 95% CI -1.36 to -0.27) and insulin (-0.49, 95% CI -0.93 to -0.04).
   Diabetologia, 2009 · checked 2026-09-24
4. dal-r2-02 · meta-analysis of RCTs
   Dietary pulses produced a 31% greater satiety incremental area under the curve (IAUC) (RoM = 1.31, 95% CI: 1.09 to 1.58, P = 0.004
   Obesity (Silver Spring), 2014 · checked 2026-09-24
5. dal-r2-07 · randomised crossover trial
   Moreover, the mean peak rise in plasma glucose was decreased by 82.1% with bengal gram dal, 67% with rajmah, while wheat and rice showed reduction only by 25 and 16%, respectively, when compared with dextrose.
   Am J Clin Nutr, 1981 · checked 2026-09-24
6. dal-r2-05 · randomised controlled trial
   HOMA-IR increased in CON (+1.2 units) and decreased in a dose-dependent manner in MOD (-0.9 units, P = .03) and HI (-1.5 units, P < .01) relative to CON. Most participants (87.4%) reported no to mild GI symptoms.
   Nutr Res, 2022 · checked 2026-09-24
7. dal-r2-04 · randomised controlled trial
   Daily consumption of mungbean dal along with guava did not result in an overall improvement of body iron stores [mean treatment effect: 0.65 mg/kg body weight; 95% confidence interval (CI): -0.34, 1.63; P = 0.197]. ... However, compared with children who consumed mungbean dal only, children in the guava group showed a larger increase in hemoglobin concentration (3.7 g/L; 95% CI: 1.6, 5.6; P = 0.001), and a larger drop in the prevalence of anemia (-51%; 95% CIs: -74, -10; P = 0.022)
   J Nutr, 2024 · checked 2026-09-24