The glycemic index is a number that ranges from 0 to 100 and indicates the rate at which the carbohydrates in that food are digested and absorbed.
The glycemic index is measured by comparing the effects of a given food containing carbohydrates with that of pure glucose, which has been assigned a glycemic index of 100. Foods with a high glycemic index (70 or higher) cause a rapid increase in blood sugar and insulin levels . Foods with a low glycemic index (55 or lower) are broken down more slowly and therefore cause a gradual rise in blood sugar and insulin levels.
What happens when we eat carbohydrates? These are broken down into glucose in the small intestine, which is then absorbed into the bloodstream. Rising blood glucose levels trigger the release of insulin from the pancreas.
Insulin helps store glucose in cells for energy or convert it to fat for storage. The rate at which this process occurs varies greatly depending on the type of carbohydrate consumed.
High-GI foods cause blood sugar and insulin levels to rise and fall rapidly, while low-GI foods cause a slower, more constant rise and fall.
Foods are generally classified into
- Low glycemic index foods: 55 or less
- Medium glycemic index foods 56-70
- High glycemic index foods: 70 and above
However, the glycemic index has limits . For example, individual response to different carbohydrate foods can vary from person to person due to differences in digestion rate and other factors such as the amount of fat or fiber consumed with the same meal. The glycemic index for the same food can vary greatly based on ripeness and cooking method.
The glycemic load (GL) is a concept that has been gaining momentum in recent years. It's a number that measures the impact carbohydrates have on blood sugar levels , a crucial factor in the development and management of type 2 diabetes, for example.
Furthermore, the glycemic load (GL) , which takes into account both the GI value and the amount of carbohydrates actually consumed per serving, may be more accurate than GI alone in predicting how certain foods affect blood sugar levels over time .
To calculate glycemic load (GL), the following formula is used:
GL = (GI x amount of available carbohydrates per serving) divided by 100.
The result of this calculation is then expressed in terms of grams of carbohydrates per serving.
An example of this in action would be a slice of white bread, which has a GI of 70 and contains 15 grams of carbohydrates per slice.
GL = (70 x 15) / 100 = 10.5 grams.
GL values range from 0 to 100 and can be classified as follows:
- Low GL: 0 – 10
- Moderate WG: 11am-7pm
- High GL: 20+
In general, foods that are low on the glycemic index are most beneficial for those trying to get their blood sugar levels under control.
The benefits of a low GI/GL diet are many.
It can help with weight loss . Low GI diets have been shown to help people lose weight and improve their overall health by reducing hunger and cravings for sugary snacks between meals.
It can help reduce the risk of developing type 2 diabetes , as it can reduce the amount of insulin needed to balance blood sugar levels.
For those who already have type 2 diabetes, a low-GL diet can help reduce the amount of medication needed, as well as the risk of developing further complications.
