The Glycaemic Index (GI) is a relatively new concept but has entered the mainstream in the last couple of years. Now many food products advertise as low GI, which appeals to the health conscious. If you’re not familiar with GI or want a handy list of common items and their GI values, check the official table or use the infographic below.
Looking at the ranking you might be surprised at how high or low the GI of certain foods is. Ice-cream, for example, is low on the GI scale indicating that it’s good for you, right?
Wrong. Ice cream is not good for you no matter what way you look at it. By now you’d be thinking that there are inconsistencies in how the GI ranks certain foods. Highly refined foods are high on the list, where you’d expect, but surely Ice cream can’t be ranked as having a lower GI than pasta?
At first glance, the table seems obvious and for the most part, it is. We all know that sugar (by this I mean refined sugar) is bad for you. Surprise, surprise it tops the list. (As an aside what may come as a surprise to many people is that pasta is high GI. At least white pasta is. There is little nutritional value in ordinary pasta and it is a fast-acting carbohydrate. So why is it touted as a health food? )
Getting back to the main point – if the GI has suspect entries how will we know for sure whether a food is going to cause blood sugar levels to rise quickly, thus giving us a sugar rush and the dreaded slump afterwards. Forget the GI, there’s a new kid in town. He’s more refined (wrong choice of words?) and he’s known as GL, which stands for Glycemic Load.
Glycemic Load – A Better Scale
The GL is a better way to evaluate a foods ‘goodness’ or its ability to maintain our blood sugar levels and give sustained energy. The Glycemic Load for me seems to be a more common-sense approach. Sticking with the example of ice cream, according to the G.I. it is quite low on the scale. Now everyone knows that ice cream is loaded with sugar as is not ideal for health. The reason it’s low is that it contains a large amount of fat as milk proteins, both of which provide slow-release energy.
This is a key point in selecting foods for optimal nutrition. Fats and slow-acting proteins combined with high-GI foods help to slow down the sugar release time of the high-GI foods alone. A similar issue relates to supposedly high-GI foods such as watermelon. Watermelon is quite near the top of the list, in the same league as table sugar (which has a GI of 100), but the fruit contains a lot of water. After eating a few large slices of watermelon your sugar levels would hardly change as the bulk of the food helps ‘dilute’ the concentrated sugars.
Table sugar, on the other hand, is highly concentrated and has a high GL.
The GL has different rankings for food than the GI, but it’s a more sensible index to base your optimal nutrition plan on. What’s the moral of the story? Try to eat high GI foods with low GL foods or foods containing fat, fibre, or protein. This will help to maintain energy levels, without sugar rushes.
CrossFit fan. Ex-personal trainer, triathlete, and cross-country mountain biker. Masters Competitive CrossFit athlete. Writer and blogger.