Hey, What’s All the Fuss About?
There is great concern these days over the dramatic rise in insulin resistance, pre-diabetes, and diabetes, resulting in the importance of understanding the glycemic index. Although the system has its weaknesses and cannot be used in isolation of other nutritional factors, it does seem important to have a basic understanding of GI and its partner GL. We would all love to understand it without going back to college for a semester. What is all the fuss in a nutshell?
How do they assign those Glycemic Index numbers?
The Glycemic Index (GI) is a ranking system in which carbohydrates are assigned a number between 0 and 100 assessing their effect on blood glucose levels. Sugar or glucose is set at 100 and is the number by which all carbs are relatively measured. Using this standard, a GI of 70 or greater is considered high, 56-59 is rated medium and 0-55 is classified as low.
But how do these high or low glycemic indexes affect me?
A low GI causes a slower rise in blood glucose levels. We digest and absorb low GI foods slowly. Think of “low means slow.” We digest and absorb high GI foods more quickly, causing rises or fluctuations in blood pressure and therefore insulin levels. Think “high GI, high blood pressure.” Our bodies stop burning fuel and store excess calories as fat when we have high GI levels. Yikes! High GI foods also make you hungry much sooner and have lower satiability (that wonderful and elusive quality of making us feel full.) Don’t think you have all the information yet because there is more to this picture!
Now that you understand a bit about GI, what are these extra letters “GL” all about?
GL stands for Glycemic Load. GL estimates the impact a carbohydrate has on your blood sugar levels. This is done by using a formula which takes into account the amount of carbs consumed in a serving of that particular food. You can do this yourself by looking at the number of grams of carbs found in a serving of food. Now multiply that by the GI and divide by 100. Too much work? Download a chart to keep handy. Or you can be like me and keep an app on you phone. Yay for apps.
But why care about the glycemic load?
Think about it. Even though watermelon lists a high GI (72) it actually only contains 5 grams of carbs per serving. Multiply those two numbers together and divide by 100 and you will find the GL is 3.6, making it a healthy choice eaten in moderation. GL’s over 20 are high, 11-19 medium, and less than or equal to 10 is low.
Becoming an expert in GI is not, as my mom would say “a do all end all.” Often people slow down on fruits and vegetables when they see a higher GI. Woah. We must take into account the GI, the GL and the overall vitamin and mineral benefits of the food.
So what’s the bottom line?
Low GI diets can decrease our risk of many cancers, gall bladder and kidney disease. Watching your GI and GL can lower risks of strokes, heart disease and other illnesses. With even this elementary lesson in glycemic indexes you can see that keeping an eye on both the GI and GL in your regular diet is definitely part of a great food plan. And don’t forget, eggs have a GI and GL of zero!