Foods That Cause a Spike in Blood Sugar

Understanding how food affects blood sugar level and constantly monitoring it is a way of life for those with diabetes. This largely involves the balance between the amount of insulin currently in the body at any given time and how the foods we eat change that it. At center stage for this daily drama are carbohydrates. Knowing the difference between how the various types of carbohydrates are processed by the body is key to maintaining blood sugar levels.

In the past, it was believed that we could classify carbs as being simple or complex, and that would be sufficient in determining their effectiveness. That did prove to be adequate. This lead to the development of the glycemic index, which does a much better job of categorizing carbohydrates according to their effect on blood sugar.

The glycemic index uses a scale that indicates how quickly and how much different carbs raise blood sugar levels after they have been eaten. Foods with a low glycemic index, 55 or less, are digested more slowly and prompt a more gradual increase in blood sugar. For diabetics, and everyone really, the lower the number, the better. Some of the characteristics that determine the score are:

Processing – the more a grain has been milled and processed, the higher the index.

Physical form – whole grains are digested more slowly, like brown rice instead of white rice, which has had the bran and much of the germ removed, reducing the fiber significantly.

Fiber content – the more fiber in a food, the less digestible carbohydrate, which slows the rate of digestion.

The ripeness of fruits and vegetables – the riper the higher and more easily accessed sugar content. 

Fat content and acid content – adding fat or acid to a meal slows sugar production and modifies the glycemic effect.

There is more to monitoring carbohydrates than just the numbers on the scale. The glycemic index tells us the type of carbohydrate in a food, but controlling glucose levels requires also monitoring portion size. In addition, combining foods from different ends of the scale can help to balance the effect on blood sugar levels.

That said, there are foods on the high end of the glycemic index that those with diabetes are cautioned to avoid or, at the very least, limit. Examples of these include:

  • white bread or bagels
  • cereals like corn flakes, puffed rice, bran flakes, instant oatmeal
  • short-grain white rice, pasta
  • russet potato, pumpkin
  • pretzels, rice cakes, popcorn, saltine crackers
  • melons and pineapple

No two people are affected exactly the same way by diabetes or by the foods they eat. It is important to consult with your doctor and be proactive in monitoring and adjusting all aspects of your lifestyle in order to maintain optimum blood sugar levels.