Cornmeal glycemic index (GI)
Cornmeal is a coarse flour made by grinding dried maize corn. It’s very rich in carbohydrates due to its high starch content.
Based on numbers from The International Tables of Glycemic Index Values, cornmeal, which has been boiled for two minutes in salted water, has a glycemic index of 68 (1).
Cornmeal with added margarine has a slightly higher GI of 69. This makes the glycemic index of cornmeal fall in the medium category.
The GI of cornmeal porridge from China is very similar, falling in the range of 68±3 (1).
A staple dish from West Africa, kenkey, prepared from fermented cornmeal, has a GI of 44±6.
Research has shown that cornmeal, cooked and stored for some time, may produce a higher glycemic index than freshly cooked cornmeal (2).
Another aspect of cornmeal that changes its glycemic response is the amylose content. Corn flour, which is high in amylose, produces lower glycemic and insulinemic responses (4).
All in all, cornmeal, high in starch, is a medium glycemic index food. However, this index can be somewhat lowered by different production and consumption methods, such as adding vegetables and fiber-rich foods or protein.