Q: We count carbs, but after a few months of rocky numbers, our dietitian recommended we take a look at the glycemic index of the foods our son eats. How can this help?

A: Since the start of blood sugar monitoring for children with type 1 diabetes, diabetes educators have heard from patients that certain foods seem to affect their blood sugar levels differently than others. Have you ever noticed that your son can eat two foods containing the same number of carbohydrates per portion, but afterwards have very different meter readings? What’s been discovered to help explain this is something called the glycemic index.

In basic terms, the glycemic index (GI) provides a measure of how quickly blood sugar levels rise after eating a particular food. Just like looking up the carbohydrate count of a food, charts are also available that show the glycemic index of many commonly eaten items. Foods that have a low GI are often higher in fiber. Fiber allows for a slower breakdown of carbohydrates, resulting in fewer blood sugar fluctuations and a feeling of fullness. Foods that are high on the glycemic index often contain refined sugars and processed grains and flours; carbohydrates in these foods tend to be more readily absorbed.

In some ways, the glycemic index is limited because it was based on the consumption of single foods rather than a mixed meal; and it was based on a fixed portion of 50 grams. However, the concept of GI can be helpful when making food choices. If you look back at what your child ate over the past few weeks, are there any particular foods that jump out as possibly being high GI? These are probably foods to take a closer look at. One way to check the effect of different foods on blood sugar is to pay attention to portion sizes and check blood sugar before and two hours after a meal containing the food.

In general, studies show that the total amount of carbohydrate in foods is still a stronger predicator of blood sugar response than the GI. This means that looking up a food’s glycemic index value does not replace counting carbohydrates. However, combined with carb-counting (which focuses on the quantity of food), adding lower glycemic index food choices can help your child focus on the quality of carbohydrates in his diet. This might result in picking whole fruit instead of processed carbohydrates such as a brownie when it’s time for a snack, or opting for whole grain breads and cereals. Since it’s all about balance, taking into account GI could be one more way to help your child choose foods that are healthy and tasty to eat.

–Colleen Farley-Cornell, M.S., R.D., C.D.N., C.D.E., is a registered dietitian and certified diabetes educator at Winthrop University Hospital in Mineola, N.Y.


How Other Parents Deal
“For us, the added bonus of foods that are lower on the glycemic index is that they do a better job keeping my growing boy filled up! Switching over to fiber-rich whole grains and chopping up a fresh fruit salad for snacks and dessert has been very easy, and it’s also meant fewer of the ‘But mom, I’m starving!’ complaints. I think we all feel healthier since switching to a whole-foods diet. It’s a way everyone in the family can eat.”
–Cassie S., Bedford, N.Y., mom of 18-year-old Jonathan


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Disclaimer: The information in these articles is not intended as medical advice. Families should check with their healthcare professionals regarding individual care.