Back to Ask the Diabetes Team Ask the Diabetes Team

From Fresno, California, USA:

I am Type 2, 47 years old, diagnosed 5 years ago. I have good control of blood sugars (last A1c was 7.0), but having a hard time controlling my lipids. I was eating a bowl of hot oat bran every morning, but found it really elevated my blood glucose. I tried oatmeal, which didn't elevate my blood glucose but is not as effective against high cholesterol. Why is oat bran so high on the glycemic index and oatmeal so low? It just doesn't make sense to me. I'd be happy to hear from anyone about this.


I talked to one of our nutritionists, and we agreed that there are probably two separate processes that contribute to your observation that the glycemic index of oat bran is higher than oatmeal.

Oat bran, I was told, was much more finely ground than oatmeal and this would make the starch more easily hydrolysable in the upper bowel and facilitate its absorption as glucose.

There is also the effect of the fiber content. Fiber will adsorb both water and a number of other water soluble small molecules like glucose and to some extent fatty acids; but for glucose to be available for this process the fiber must be saturated with water. Bran is usually eaten without being soaked in water whereas oatmeal is usually briefly expanded in boiling water. This means that the fiber in oatmeal is more ready to adsorb glucose in the upper small bowel than bran. For the same reasons, the latter is better able to alleviate constipation.


Original posting 29 Jul 97


  Home Return to Top

Last Updated: Tuesday April 06, 2010 15:08:54
This Internet site provides information of a general nature and is designed for educational purposes only. If you have any concerns about your own health or the health of your child, you should always consult with a physician or other health care professional.

This site is published by T-1 Today, Inc. (d/b/a Children with Diabetes), a 501c3 not-for-profit organization, which is responsible for its contents.
By using this site, you agree to our Terms of Use, Legal Notice, and Privacy Policy.
© Children with Diabetes, Inc. 1995-2015. Comments and Feedback.