You may think a slice of watermelon would be the healthier choice over a donut (and you would be right), but did you know that both foods are considered to have rather high sugar content according to the Glycemic Index (GI) scale ? The GI is useful for understanding how the body breaks down carbohydrates.
The Glycemic Load (GL) is a number assigned to a food that estimates how much that food will raise a person’s blood glucose level after eating it. Knowing the GL of a food in addition to where it lands on the GI scale can make all the difference in your future food choices.
What is Metabolic Syndrome?
You’ve heard it since you were a child: consuming excess sugar is bad for your health. However, there’s an actual condition it can lead to called Metabolic Syndrome. This condition is characterized by:
- High blood pressure
- High blood sugar
- Unhealthy cholesterol levels
- Abdominal fat
Excess sugar also contributes to widespread inflammation throughout the body, and even leads to a higher risk of developing cardiovascular disease and type 2 diabetes.
When eaten in an uncontrolled manner and at high levels, sugar can harm organs as well. We know it can have damaging effects on the pancreas and insulin secretion. Too much sugar circulating in the body starts to react with cell tissues and blood vessels in the brain, the eyes, the heart muscle and all types of blood vessels leading to wide-spread damage.
The Difference Betwen Glycemic Index and Glycemic Load
The Glycemic Index (GI) is a number associated with a particular type of food that indicates the food’s effect on a person’s blood glucose (also called blood sugar) level. The GI represents the total rise in a person’s blood sugar level following consumption of a food; it may or may not represent the rapidity of the rise in blood sugar. The steepness of the rise can be influenced by a number of other factors, such as the quantity of fat eaten with the food.
While the GI is a useful tool for understanding how the body breaks down available carbohydrates (total carbohydrate minus fiber), it doesn’t take into account fats and other components that contribute to the total rise in blood sugar. This is where the Glycemic Load (GL) provides useful feedback. The concept of GL was developed by scientists to simultaneously describe the quality and quantity of carbohydrates in a food serving, meal, or diet.
Consider the example of the watermelon and donut. The GI of watermelon is 72, which is almost as high as the GI of a doughnut which is 76. Yet, one serving of watermelon provides 11g of available carbohydrates, while a medium donut provides 23g of available carbohydrates. That is an over 50 percent difference in how quickly an available carbohydrate can raise your blood glucose level.
It’s a common misconception that all low-GI foods are healthy foods. While this is generally the case, it is not always true. Parsnips, strawberries and bananas are widely considered to be healthy foods, and yet they all rate as intermediate-to-high foods on the GI scale. But, on the GL scale, one cup of strawberries rates a 13, bananas are a 16 and parsnips are only a 4.
What is a Good Glycemic Load Level?
For a typical serving of a food, the GL scale would be:
- 10 or less = low (good)
- 11 – 19 = medium
- 20 or above = high (bad)
Using our original example, despite similar GIs, one serving of watermelon has a GL of 4, while a medium-sized doughnut has a GL of 205.
Meanwhile, a GI scale works by rating numbers from low (good) to high (bad). The smaller the number, the less impact the food has on your blood sugar:
- 55 or less = low (good)
- 56 – 69 = medium
- 70 or higher = high (bad)