Carbohydrates within the foods we eat can be released into the body at different speeds. The glycemic index (GI) is a measure of how quickly carbohydrates within a food are released. According to the International GI Database, any food with a GI of 70 or above is classed as having a high GI. Foods with a high GI release carbohydrates quickly and can cause your blood sugar levels to rise and fall irregularly. Foods with a lower GI can help keep blood sugar levels stable.
Features
The majority of fruits and vegetables have a low glycemic index, thanks to their low carbohydrate content. In general, fruits tend to have higher GI ratings than vegetables because of their natural sugars.
Prevention/Solution
According to the GI database, watermelon has a GI of 72 per 120 g serving. You can counteract this high GI by serving watermelon with other fruits that have lower GI ratings. Try snacking on watermelon and grapes, or have a tropical fruit salad for dessert. Include plenty of fresh pineapple, mango, kiwi and strawberries. Canned lychees in syrup also have a high GI rating. Try fresh lychees, as this will bring their value down from 79 to 57.
Potatoes
Potatoes generally have a high GI rating, but there are variations between the different types of potato and the way they are prepared. According to the database, a quartered Desiree potato has a GI of 77 after being boiled for 15 minutes. A Maris Piper potato prepared in the same way has a GI of 94. Swap these varieties for Charlotte potatoes to reduce the GI to 66. Bake potatoes with the skins on, as they have a lower GI of 69 compared to peeled potatoes. You can reduce the GI of a baked potato further by adding low GI toppings, such as tuna and sweetcorn or baked beans.
Sweet Potatoes
Sweet potatoes have different GI values depending on the variety and the way you cook them. According to the database, a sweet potato of the Ipomoea Batatas variety can have a low GI of 44 if you boil it. This will rise to 76 if you peel and fry it in vegetable oil, or 94 if you peel and bake it. You can counteract this high GI by serving your sweet potato with grilled fish or chicken and vegetables.
Vegetables
According to the database, other vegetables with high GI values include broad beans and parsnips. Broad beans have a GI of 79, and parsnips have a GI of 97.
