The GI Diet

Finally, here is a diet which has some solid scientific research behind it! The Glycemic Index diet relies on research done by Toronto University professor Dr David Jenkins, who discovered that the body reacts differently to different carbohydrates, regardless of their actual caloric value. Jenkins realised that some carbs are broken down quickly in the intestines and cause a rapid rise in blood sugar. These are the foods which make dieting difficult, since they unbalance the natural glucose- insulin mechanism which keeps blood sugar stable, and make you feel hungry.

Unlike low-carb diets like Atkins, the GI diet doesn't recommend cutting out carbohydrates completely for any length of time. Instead, the guiding principle is the Glycemic Index, which divides carbohydrates into three groups. Glucose is the highest glycemic index food, with a value of 100, and all other carbohydrates are placed on a scale from 1 to 100. Low glycemic index carbohydrates are those which break down into sugar slowly, and help keep you feeling full for longer, and have values up to 55, medium glycemic index foods are 55 to 69, and all foods above this are the real baddies.

Glycemic index foods

Most of the highest glycemic index foods are the highly processed ones, since the bran which naturally coats the grains and slows digestion has been removed. Wholemeal bread is lower in the index than white, and added bran flakes can lower the glycemic index of any meal. The old saying that lentil soup 'sticks to your ribs' and keeps on giving energy all day turns out to have a grain of truth, since it is one of the low glycemic foods! Surprisingly, so are milk chocolate and sweet potatoes, while foods which seem to be good diet options like rice cakes are actually high glycemic index foods. Most high protein foods are low glycemic index, even those which contain calories from fat, because protein and fat slow the absorption of carbohydrate.

There are several GI diets on the market at the moment, and although all use the glycemic index as a basic guide, they also tend to curb calorie intake as well. It turns out that it isn't enough, unfortunately, just to change the type of carbs we eat, although this definitely makes dieting easier. Probably the best known is Rick Gallop's "GI Diet" , which uses a 'traffic light' approach to regulate carb intake, and integrates the glycemic index with a fairly well balanced calorie controlled diet and a recipe base. Anne Collins also offers a GI diet, although hers seems rather short, ending after four weeks, whereas Rick Gallop encourages an ongoing change in nutrition to keep weight down permanently.

Doctors quite like the GI diet, as it does have a lot of good nutritional points. Eating less processed foods is obviously better for you, and keeping blood sugar level reduces the risk of developing diabetes and heart disease. Some doctors point out that the actual glycemic index of any meal is influenced by all the foods eaten at that meal, and may be difficult to calculate.