Glycemic Index: Good vs. Bad Carbs

Glycemic Index: What's It All About?

Good carbohydrates, bad carbohydrates. Low glycemic index, high glycemic index. A great tool to help you lower your glucose levels or lose weight. You might have heard all these statements associated with the glycemic index. What is this glycemic index all about? Is it worth considering as a way to help you control your blood glucose levels?

The Glycemic Index: Measuring a Food’s Impact on Blood Glucose Levels

Researchers have spent years debating what makes blood glucose levels too high. Potential culprits have included sugar, carbohydrates in general, simple carbs, starches, and more. The glycemic index is one attempt to measure each individual food’s effect on blood glucose levels.

If you're trying to lose weight, calories count more than the types of food in your diet, a U.S. Department of Agriculture-Tufts University study shows.

High Glycemic Index Foods Are Linked to Health Problems

What researchers have learned is that high glycemic index foods generally make blood glucose levels higher. In addition, people who eat a lot of high glycemic index foods tend to have greater levels of body fat, as measured by the body mass index (BMI). High BMIs are linked to obesity, heart disease, and diabetes.

High glycemic index foods include many carbohydrates such as these:

• White bread
• Pasta
• Rice
• Low-fiber cereals
• Baked goods

Low Glycemic Index Foods Are Healthier Choices

Low glycemic index foods generally have less of an impact on blood glucose levels. People who eat a lot of low glycemic index foods tend to have lower total body fat levels.

Low glycemic index foods include these:

• Fruits
• Vegetables
• Whole and minimally processed grains
• Legumes

Glycemic Index and Your Diet

You can find lists of low (good), medium, and high (bad) glycemic index foods on the Internet or in books. A dietitian can also point you to lists of these foods. Choose foods from the low and medium end of the glycemic index as often as you can. Avoid foods high on the glycemic index.

But what can you do if you need to eat and a glycemic index food list is not available?  Keep this general principle in mind:

Unprocessed foods tend to have lower glycemic indices than refined foods.

Many packaged food products list the glycemic index, although it is not required. For reference, use this glycemic index chart to interpret the numbers:

• Low (good) glycemic index levels: 55 or less
• Medium glycemic index levels: 56–69
• High (bad) glycemic index levels: 70 or higher