Are Low Glycaemic Index Diets Any Good?
Developed by a Dr David Jenkins in the early eighties to help diabetics stabilise their blood-sugar levels, the Glycaemic Index (GI) has revolutionised the diet industry, with many nutritionists now advocating it as the best way to stabilise blood-sugar levels, increase energy levels and of course encourage fat loss.
For all the controversy that Dr Atkins created by preaching the benefits of low-carbohydrate diets, he certainly made a lot more people aware of the impact that certain types of carb can have on our insulin levels. Although vilified by many nutritional scientists for his method of dieting, the underlining point made by him on the importance of stabilising blood-sugar levels to improve energy levels and control body fat is upheld by all nutritionists.
All forms of carbohydrate, from a candy bar to a crumpet, initiate an insulin response. If too much insulin is secreted too quickly, a ‘blood-sugar spike’ occurs. In the immediate instance, this not only causes lethargy, but if the body is consistently asked to produce large amounts of insulin to utilise excessive quantities of sugar, it can lead to weight gain and eventually Type 2 diabetes. For this reason the Glycaemic Index was devised. By providing a guideline as to how much insulin your pancreas secretes for every type of food, you are in a far better position to be able to regulate your blood-sugar levels.
The exact method used to calculate the GI of food varies, but by far the most common way is by comparing the insulin response a food has with glucose. As the simplest form of sugar, glucose initiates the greatest insulin response of any other food and therefore has a GI of 100. All other foods are therefore subsequently given a value and a class: high, medium or low GI. A few examples include:
High Medium Low
Glucose 100 Milk 61 Meat 0
Potatoes 93 Ice cream 61 Fructose 23
White Bread 70 White Rice 58 Fat 0
Note: These values are a general guide and will vary from source to source.
Following a diet rich in foods that are low on the GI, such as vegetables, wholemeal breads and pasta, is certainly recommended by many nutritional experts, but try to avoid getting too carried away by obsessing over low GI foods. Although all meats, cream and butter are low on the GI, they are also high in saturated fat and cholesterol. The general advice I give to my clients is to eat wholemeal carbohydrates such as brown pasta and to limit large quantities of fats, despite their low GI value. The Glycaemic Index is an extremely good guide to healthy eating and will help you stabilise your blood-sugar but it should not rule your dietary life.