The glycemic index (GI) is a measure of your body’s blood sugar response after eating a carbohydrate.
A food with a GI of 100 is rapidly digested and absorbed by the body causing a short, sharp rise in blood sugar. A food with a low GI ( under about 55ish) is digested and absorbed more slowly, so the blood sugar rise is slower and longer lasting.
Consuming a meal of mostly high glycemic index carbohydrates is generally a bad thing. The blood sugar rise causes a large release of the hormone insulin, and in this environment the body does not burn fat. So a bad thing for weight loss. Diets with lots of high GI carbohydrates are associated with diabetes, obesity, heart disease, high cholesterol and other ‘lifestyle’ diseases.
Eating a meal with a mixture of low GI carbohydrates will provide your body with slow release, sustained energy, controlled blood sugar and insulin levels and a good environment for burning fats.
So what foods have a low GI?
Let’s start with some foods that have no GI. How does that work?
GI is an indication of the response to carbohydrate intake, so foods with no carbs don’t have a GI. As such, meats, alcohol, tofu and other proteins or fats don’t have a GI.
Some foods with a high GI include:
- white bread
- wholemeal bread
- white potatoes
- most white rice varieties, especially Jasmine
- rice pasta and rice crackers
Some foods with a lower GI include
- pasta (!)
- split peas
- sweet potato
- multi grain bread
- fruit (with a few exceptions)
For a comprehensive database of GI values, and some excellent additional information, visit here.
But remember, low GI foods are not a magic bullet. There a plenty of low GI foods that are high in fat, and not really a sensible everyday choice. And there are some high GI foods that definitely have a place in a balanced diet.
The key is balance, through substituting low GI choices for high GI choices in the majority of meals. And sticking to the good old healthy eating pyramid.
And for those of you in hard training, note this:
Your post exercise, high carb intake within 30 minutes of exercise should be high GI foods, for rapid absorption and replenishment of muscle glycogen stores.
If you would like to know more about the glycemic index and what it means for your health, please see here.