Glycemic Index vs Glycemic Load: What's the Difference?
If you're on a low carb diet, no doubt you've heard all about the glycemic index and the glycemic load of certain foods. You know that higher GI and GL is bad, but you're not quite sure what it means. In order to make your life just that much easier, we're here to explain to you the difference between the glycemic index and glycemic load.
The glycemic index of a food determines the amount of sugar that it has. Regular bottled water, for example, has a GI of 0 - no sugar in it. Table sugar - the stuff you put in your coffee - has a GI of 100, because it's pure sugar.
Not all foods have the same amount of sugar, hence the different GI rankings for each of the foods. The foods that are low on the Glycemic Index have a ranking of lower than 55. Foods that are ranked medium on the GI are between 56 and 70. Foods that are high on the GI have a ranking higher than 71.
What does this mean? Simple: the higher the ranking of a food, the more carbohydrates - essentially sugar - it has.
For example, white bread has not as much sugar, but it is very high in carbs. It has a ranking of 72 on the Glycemic Index, meaning it will cause very noticeable effects on your blood sugar levels. Now compare that to soy beans, which have a GI of 18. The very low GI ranking means that you can eat soy beans without having to worry about the effect they have on your blood sugar.
Diabetics, those on low carb diets, and people trying to control their blood sugar will want to choose not just low GI foods, but also foods with a low Glycemic Load ranking.
To understand what the difference is between the GI and the GL of a food, you have to understand that all food is made up of carbohydrates, vitamins, minerals, proteins, fats, and, in many cases, fiber.
Fiber is a wonderful nutrient, as it will prevent your body from absorbing the sugars and starches in your food. Not all of the sugars and starches will be absorbed, but enough to reduce the effects of your good.
This is essentially what the GL is. You simply take the Glycemic Index of your food, and subtract the amount of sugar negated by the fiber you've eaten.
For example, carrots rank pretty high in the GI, as they have a lot of sugar in them compared to other vegetables. However, when you add the amount of fiber that the vegetables have, you'll find that their GL ranking is much lower than their GI ranking. This is because the fiber cancels out the amount of sugar in the food, bonding with it and preventing it from being absorbed into your body. This means that you can eat carrots without having to worry about causing a spike in your blood sugar.
So which is more important? For the average person, following the Glycemic Load rankings is the best. You'll find that the GL of foods will help you to determine the nutritional value of what you're about to put into your body, and will ensure that you don't see spikes in your blood glucose levels. You can keep your blood sugar under control, all because you're eating foods that are either lower in sugar or which have enough fiber to prevent the sugar from being absorbed too quickly into your body. It's the smart way to eat!