Teff: an iron grain whose iron is hard to absorb

In a stable-isotope study on 22 healthy women aged 21 to 29, median iron absorption from iron-fortified injera made with 100 percent teff was 1.5 percent. Replacing 10 percent of the teff with whole wheat flour raised it to 5.3 percent, and adding a phytase enzyme raised it to 3.6 percent. The abstract does not say the meals were given in random order. So teff is sold on its iron, and the best data so far say that iron is hard to get at. For weight and blood sugar there is one non-randomized comparison of 28 overweight adults. Three months on a teff diet lowered fasting glucose and LDL, and HDL fell too, while weight did not change compared with a Mediterranean diet. The abstract gives no sizes for those changes. We found no trial of teff in people with celiac disease.

The numbers, per 3.5 oz (100 g)

How much is actually in it

• Per 100 g, cooked teff lists 50 mg magnesium and 0.226 mg copper against 184 mg and 0.81 mg in dry grain, mostly from water uptake. — USDA SR Legacy, one cooked and one uncooked record (n = 2 food records) Evidence E source
  Cooked: magnesium 50 mg, copper 0.226 mg, thiamin 0.183 mg; uncooked: magnesium 184 mg, copper 0.81 mg, thiamin 0.39 mg

What your body absorbs

• Iron absorption from fortified teff injera was only 1.5% in 22 young women and rose to 5.3% when 10% of the teff was replaced by whole wheat flour. — healthy normal-weight women aged 21-29, study A n=22, stable iron isotopes (n = 22) Evidence C source
  Median fractional iron absorption 1.5% (IQR 0.7-2.8) vs 5.3% (2.4-7.1) with wheat flour, 3.6% with A. niger phytase
• Three to four slices of teff bread supplied 7.6 mg iron versus 5.1 mg from control bread, with phytase giving the best serum iron curve. — 24 non-pregnant women aged 20-50, five allocated groups, 180-210 min follow-up (n = 24) Evidence C source
  7.6 mg vs 5.1 mg iron (P<0.001); smallest serum iron fall with high phytase (-0.3 vs about -1.5 micromol/L)
• Across 19 studies of millets including teff in anemic people, hemoglobin rose 13.2% versus 2.7% on usual diets. — 30 studies (22 human, 8 in vitro) of finger millet, pearl millet, teff and sorghum (n = 19 studies) Evidence C source
  Hemoglobin +13.2% vs +2.7%; in vitro fermentation and germination raised bioavailable iron 3.4 and 2.2 times

What it does to your health

• In 28 overweight adults, 3 months on a teff seed diet lowered fasting glucose and LDL but did not change weight versus a Mediterranean diet. — 28 overweight and obese adults, teff diet n=14 vs Mediterranean diet n=14, 3 months (n = 28) Evidence C source
  Significant falls in fasting glucose, cholesterol, LDL and HDL in teff group; no anthropometric difference

Safety, limits and interactions

• A 29-year-old man had mouth itching, tongue swelling and trouble swallowing after teff flakes, the first reported teff allergy. — 1 adult male with occupational exposure, Poland (n = 1) Evidence D source
  Oral allergy symptoms; skin test to teff flour 22/60 mm
• A man drinking large amounts of teff grain herbal tea for 5 days to lose weight had cardiac arrest with potassium of 2.23 mEq/L. — 1 adult male, 41 years, Turkey (n = 1) Evidence D source
  Serum potassium 2.23 mEq/L, ventricular fibrillation, recovered

Who this works differently for

• In a 6-week RCT of 34 pregnant women, teff-based iron-rich bread left 12% iron deficient versus 27% on placebo bread. — 34 Caucasian primiparous antenatal patients, 6 weeks, about 2.3 slices a day (5.0 mg iron) (n = 34) Evidence B source
  Iron deficiency at end 12% (teff bread) vs 27% (placebo); other iron markers not better
• Ethiopian pregnant women eating teff injera once in 2 weeks had 3.17 times the odds of anemia of daily eaters. — 592 pregnant women in Addis Ababa, 187 anemic cases and 405 controls (n = 592) Evidence C source
  AOR 3.17 (95% CI 1.62 to 6.22) once in 2 weeks vs every day; 2.13 (1.03 to 4.41) for 1-2 times a week

The bottom line

Per 100 g, cooked teff in the USDA tables lists 50 mg magnesium against 184 mg in the dry grain, and 0.226 mg copper against 0.81 mg. The cooked figure includes the water the grain takes up, and the tables give no sample spread, so the gap mixes dilution with whatever is truly lost. Two weaker studies add to the iron picture. In a trial on 24 non-pregnant women that did not describe random allocation, three or four slices of teff bread supplied 7.6 mg iron against 5.1 mg from control bread. The version with the most phytase gave the smallest fall in serum iron over about three hours. A review of millets found hemoglobin rose 13.2 percent against 2.7 percent on usual diets across 19 studies in anemic people. It pooled teff with finger millet, pearl millet and sorghum, and the studies varied widely (I2 87 percent). For pregnancy, a double-blind randomized trial on 34 first-time pregnant women gave an iron-rich bread for six weeks, about 2.3 slices and 5.0 mg of iron a day. At the end 12 percent were iron deficient against 27 percent on placebo bread. The abstract gives no test of that difference, and the other iron markers favored placebo. In Addis Ababa, a case-control study of 592 pregnant women linked eating teff injera once every two weeks with 3.17 times the odds of anemia compared with eating it daily (95% CI 1.62 to 6.22). That is an association from a food questionnaire, and teff intake there also tracks food security and soil iron. Who should be careful. Teff allergy is documented in one case. A 29-year-old man in Poland, exposed to teff at work, had mouth itching, a swollen tongue and trouble swallowing after eating teff flakes. A second case report describes a 41-year-old man in Turkey who drank large amounts of a herbal teff tea for five days to lose weight and went into cardiac arrest with a potassium level of 2.23 mEq/L. The composition of that tea is unknown, and it is a different product from the grain eaten as food.

Sources

1. tef-r6-09 · reference dataset
   SR Legacy FDC 168918 Teff, cooked: magnesium 50 mg/100 g · copper 0.226 mg/100 g · thiamin 0.183 mg/100 g; SR Legacy Teff, uncooked: magnesium 184 mg/100 g · copper 0.81 mg/100 g · thiamin 0.39 mg/100 g
   USDA SR Legacy 2018, FDC 168918 Teff, cooked; Teff, uncooked · checked 2026-10-02
2. tef-r6-02 · iron absorption trial
   In study A, the median (IQR) FIA from the 100% tef injera meal was 1.5% (0.7-2.8%). This increased significantly (P < 0.05) to 5.3% (2.4-7.1%) on addition of 10% whole wheat flour, and to 3.6% (1.6-6.2%) on addition of A. niger phytase.
   Herter-Aeberli I et al., J Nutr 2020;150(10):2666-2672 · checked 2026-10-02
3. tef-r6-03 · controlled trial
   Consuming three or four slices of TB provided statistically significantly more iron (7.6mg) than CB (5.1mg) (P<0.001).
   J Hum Nutr Diet, 2012 · checked 2026-10-02
4. tef-r6-06 · systematic review
   The results of 19 studies conducted on anaemic individuals showed that there was a significant (p < 0.01) increase in hemoglobin levels by 13.2% following regular consumption (21 days to 4.5 years) of millets either as a meal or drink compared with regular diets where there was only 2.7% increase.
   Front Nutr, 2021 · checked 2026-10-02
5. tef-r6-05 · cohort
   In our study, planned as a cohort study, 28 participants followed the teff seed-containing diet (n=14) and the Mediterranean diet (n=14) for 3 months... There was a significant decrease in fasting blood glucose, cholesterol, LDL, and HDL levels in the teff group (p<0.05).
   Ethiop J Health Sci, 2022 · checked 2026-10-02
6. tef-r6-07 · case report
   A 29-year-old male presented at our clinic due to an episode of itching and burning in his mouth, swollen tongue, and difficulty swallowing following ingestion of teff flakes.
   Allergy Asthma Clin Immunol, 2020 · checked 2026-10-02
7. tef-r6-08 · case report
   The patient said that he had been consuming a large quantity of teff tea for 5 days to lose weight.
   Turk Kardiyol Dern Ars, 2020 · checked 2026-10-02
8. tef-r6-01 · randomized controlled trial
   In this double-blind, randomized trial 34 Caucasian, primiparous antenatal patients were randomized to receive intervention bread or a placebo for 6 weeks. Women consumed on an average of 2.3 slices per day, providing a total of 5.0 mg iron. Using World Health Organisation (2001) haemoglobin cut-offs, 12% of participants eating the iron-rich bread were iron deficient by the end of the study compared with 27% in the control group.
   Int J Food Sci Nutr, 2012 · checked 2026-10-02
9. tef-r6-04 · case-control
   Compared with everyday TI consumption, the adjusted odds ratios (AORs) of anemia associated with the other frequencies of teff consumption were 1.50 [95% confidence interval (CI) 0.71, 3.23; p = 0.285] for every other day, 2.13 (95% CI 1.03, 4.41; p = 0.04) for 1-2 times a week, and 3.17 (95% CI 1.62, 6.22; p < 0.001) for once in 2 weeks.
   Eur J Nutr, 2019 · checked 2026-10-02