Glycemic index

Glycemic index is a measurement of carbs and about their effect on blood sugar levels. This helps one rank foods from low to high glycemic index and is useful for people having prediabetes and diabetes. Which foods have high glycemic index and are bad for health especially in diabetics?

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What is the Glycemic index?

Glycemic index is a measure of carbs on their ability to raise blood sugar levels. Foods with a high glycemic index cause a higher blood sugar spike compared to those with a low glycemic index. Hence, the latter foods are preferred in patients with diabetes in order to control their blood sugar smoothly.

The International Organization for Standardization (ISO) has ranked foods based on their individual glycemic index values. The value of this index is any number from 1 to 100. Pure glucose has a glycemic index (GI) of 100. Some people take white bread as the reference food for the value of 100. Whatever the reference, foods are grouped into three categories:

Glycemic index
White and whole wheat bread have a GI of around 74 to 75 (Source: Real Simple)

Those with low glycemic index -55 or less
Medium GI foods – with value of 56 to 69
High GI foods – with values from 70 to 100.

The American Diabetes Association gives a list of common foods and their glycemic indices so that patients with diabetes can refer to them and prepare their meals accordingly.

Factors that affect the index

The Glycemic Index Foundation (GIF) has revealed that certain factors determine how the foods affect the blood glucose levels. These include:

-The level of refinement of the carbs – more refined the carbs, higher will be its GI.
-Physical and chemical structure of food – liquid forms of the same food product would have higher GI compared to its solid version. The chemical structure of the food also influences the value.
-The cooking methods employed – prolonged cooking breaks down the carbs in the food and this raises its GI.
-the fiber content of food – more the fiber, lower would be the GI
-Presence of other macronutrients – Combination of proteins-rich foods with the carb food would lead to lowering of the index. Fats and acids in food also affect the value and lower it.

Glycemic index
Cookies (Source: Love and lemons)

Therefore, refined and processed foods cause higher blood sugar spike. Proteins, fats, and fiber in food lowers the GI. Cooking for a longer time increases the GI. And acids such as lemon juice reduce the value.

Foods with high GI

Certain foods have very high GI. Diabetics should avoid these foods for smoother control of their blood sugars. Foods with extremely high GI value are:

White bread. Whole wheat bread also has a high GI
White rice
Breakfast cereals and cereal bars
Cookies, cakes
Sweet desserts
Potatoes and French fries
Chips and rice crackers
Fruits such as watermelon, pineapples, mangoes, bananas
Sweetened dairy foods like fruit yogurts, ice creams.

Glycemic index
Fruit yoghurt (Source: Kidspot)

Also, read Lung cancer: a diet with high glycemic index foods increases risk of this preventable cancer!

Diabetics should avoid these foods or eat them only occasionally. Even healthy adults should consume these foods of high GI in moderate amounts. This would help them prevent type 2 diabetes and also other chronic diseases of the body.