Why These Low Glycemic Foods Can Make You FatEven though it's been around for more than 20 years, the glycemic index has been in the spotlight again during the last few weeks.
As well as being covered in several issues of the Sunday Times, the glycemic index also features prominently in several new diet books.
According to The Holford Diet, for example, the way to lose weight is not to eat fewer calories than you burn. Instead, the solution is to regain control of your blood sugar levels by eating a diet with a low glycemic load.
In case you've never heard of it, the glycemic index is used to rank different types of food according to the effect they have on blood sugar levels.
• Foods that lead to a rapid rise in blood sugar have a high glycemic index.
• Foods that lead to a slower rise in blood sugar are said to have a low glycemic index.
While the glycemic index tells you how rapidly a food raises blood sugar, it doesn’t tell you how much carbohydrate is in that food. To understand how the food will affect blood sugar levels, you need to know both. That's where the glycemic load helps.
The glycemic load takes the glycemic index into account, but gives a more complete picture than the glycemic index alone. The carbohydrate in a carrot, for example, has a moderate glycemic index. But there isn’t a lot of it, so the glycemic load of a carrot is actually quite low.
So, is "balancing your blood sugar" by eating a low glycemic load diet the key to losing weight?
There's actually very little evidence to show that eating more carbohydrate-rich foods with a low glycemic index and fewer carbohydrate-rich foods with a high glycemic index - without making any other change to your diet - has much impact on weight loss at all (see The glycemic index myth revealed in the Members-Only Area for a review of the latest research).
Different foods do vary in the way they affect your metabolism . However, when it comes to losing weight, the secret to success is still to consume fewer calories than you burn.
Although the glycemic load is useful in some circumstances, it was never meant to be used in isolation. Peanuts and avocados, for example, have a very low glycemic index. But, they're also high in calories. Eat too many of them, and you'll get fat.