Glycemic Index (GI) and Glycemic Load (GL) are two important things to know about foods we’re consuming as they may play big roles in helping us reduce the risks of getting heart diseases and several types of cancer. Additionally, low GI diets can also be beneficial to prevent diabetes and obesity.
Foods with low GI are usually ones high in dietary fiber. Fiber is important due to its ability to bind large amount of liquid in our digestive tract, making us feel fuller longer. Fiber also triggers the release of leptin, hormone responsible for satiety, and controls the release of ghrelin that causes hunger.
But what are glycemic index and glycemic load exactly?
Glycemic index is a number used to show how fast the carbs we consume can be turned by the body into glucose that serves as one of our energy sources, and how fast it can increase our blood sugar levels. Glycemic index is divided into 3 categories, which are low (<55), medium (56-69), and high (>70). The higher the GI, the faster a food is turned into glucose and the faster it affects the blood sugar levels. This is why people with diabetes are ordered to avoid foods with high glycemic index.
Meanwhile, glycemic load is the number used to accurately show how much carbs get absorbed by our body from all the foods we eat. In one serving of a food, a GL lower than 10 is said to be low, a GL between 11-19 is considered medium, and a GL greater than 20 is considered high. We calculate the GL of a particular food using this following formula:
Glycemic load = (glycemic index x carbohydrate content per portion)/100
Both GI and GL are useful for us to determine which foods may be added to or should be removed from our diets. By knowing the GI, we can see how fast our blood sugar levels can be affected by a certain food. And by calculating the GL, we know how much carbs are absorbed by our body.
However, foods with low glycemic index don’t always mean they can’t affect our blood sugar levels. When consumed excessively, low GI foods will still cause blood sugar spikes. For example, 25 grams of red beans contain 17 grams of carbohydrates, has glycemix index of 20, and a glycemic load of 3,4 which is categorized as low. But when we increase the consumption to 200 grams, the IG will remain the same while the BG will increase to 24, which is said to be high.
Aside from the amount, we should also watch the combination of foods that we consume. Tea and chocolate drink that originally have low IG may turn into high GI beverages if we add sugar to increase the sweetness and enhance the taste. To keep the GI low, and keep the good flavor at the same time, we can use alternative products that we know have low glycemic index and are widely available on the market. Like FiberCreme, high-fiber multi-purpose creamer that we can find easily at stores near us, has glycemic index of 51 which is pretty low, and allows us to conveniently increase our fiber intake. To add sweetness, we can replace our regular sugar with low-calorie sweetener like stevia or monk fruit extract powder.
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Truswell, A.S. (1992) Glycaemic index of foods. Eur. J. Clin. Nutr. 46 (Suppl;. 2): S91-S101.