The Skinny on Glycemic Index
The Glycemic Index (GI) measures the immediate effect of carbohydrates on blood glucose (blood sugar) levels. Simple carbs (also referred to as "bad" carbs) are digested and absorbed quickly into the bloodstream. Simple carbs have high glycemic indexes. Complex carbohydrates ("good" carbs) break down more slowly and releases glucose gradually into the bloodstream. Complex carbs have low glycemic indexes. Generally speaking, food that contain low GI Indexes work well for weight loss because they help control appetite, delay hunger, reduce insulin levels and insulin resistance.
The Glycemic Index is measured on a scale of 1 to 100. The rankings are:
Low GI = <55
Medium GI = 56 to 69
High GI = >70
Examples of foods with high GI:
- Ice cream
- White bread
- Dried fruit
- Carrots
- Bananas
Medium GI:
- Green peas
- Baked beans
- Blueberries
- Orange Juice
Low GI:
- High fiber/low sugar cereals
- Apples
- Tomatoes
- Green leafy vegetables
In general, most foods with a low GI also contain more fiber and are low in fat. However, it is very important to remember that the Glycemic Index for individual foods alone can not be a determining factor for weight loss. Most meals are eaten in a combination with different foods which will affect the overall GI. For example, jellies/jams have a high GI ranking, but when eaten with whole wheat bread, the combination of the jelly and bread decreases the GI ranking. The whole wheat bread is digested more slowly and in effect, the jelly on the bread is digested slower than had it been eaten without the bread.