Breads · Glycemic index
Do corn tortillas spike blood sugar?
Not much. Corn tortillas have a low GI of 46, and a 24 g serving (1 tortilla) has a low glycemic load of 4. Corn tortillas are made from corn masa, have a low average GI, and a single small tortilla holds little carbohydrate.
Key numbers
- Glycemic index
- 46
- Low GI
- Glycemic load
- 4
- Low GL
- Available carbs
- 9 g
- 1.5 g fiber
- Serving
- 1 tortilla
- 24 g · warmed
GI vs GL for corn tortillas
The glycemic index (GI) compares how fast the carbohydrate in a food raises blood sugar against pure glucose (100), using a fixed amount of carbohydrate. The glycemic load (GL) adds the other half of the story — how much carbohydrate a normal serving actually contains: GI × available carbs ÷ 100. For corn tortillas: 46 × 9 g ÷ 100 ≈ 4.
That figure is an average reported in the 2008 international GI tables (“Corn tortilla: 46 ± 4 (average of multiple studies)”). The 2021 tables list two ISO-standard corn tortilla tests (49 and 52) but no mean, so the 2008 average is used.
Eating a different amount? Work out the glycemic load of your portion.
How to eat corn tortillas with less of a spike
- Use two small corn tortillas for tacos rather than one large wrap.
- Fill them with beans, grilled fish or chicken and plenty of vegetables and salsa.
- Warm them in a dry pan instead of frying them into tostadas or chips.
Other low-GI choices
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Frequently asked questions
What is the glycemic index of corn tortillas?
Corn tortillas have a glycemic index of 46, which is low. That figure is an average reported in the 2008 international GI tables (“Corn tortilla: 46 ± 4 (average of multiple studies)”). A 24 g serving (1 tortilla) contains about 9 g of available carbohydrate, giving a glycemic load of 4 (low).
Is corn tortillas good for prediabetes?
Corn tortillas are a good base for tacos and wraps: low GI and naturally small. Two tortillas with beans, fish or chicken and salsa make a balanced plate.
Are corn tortillas lower GI than wheat wraps?
Only slightly. Two corn tortillas tested 49 and 52 in the 2021 tables, while wheat-based wraps tested between 50 and 62, so portion size makes the bigger difference.
Sources
GI values come from the international GI tables; carbohydrate and fiber per serving are calculated from USDA FoodData Central.
- Atkinson FS, Foster-Powell K, Brand-Miller JC. International tables of glycemic index and glycemic load values: 2008. Diabetes Care. 2008;31(12):2281–2283, Table 1
- USDA FoodData Central, FDC ID 175036: Tortillas, ready-to-bake or -fry, corn
- Atkinson FS, Brand-Miller JC, Foster-Powell K, Buyken AE, Goletzke J. International tables of glycemic index and glycemic load values 2021: a systematic review. Am J Clin Nutr. 2021;114(5):1625–1632, Supplemental Table 1
Data last checked .