Definition | Use | Gi Food Lists
Carbohydrates generally contain energy, fibre, vitamins and minerals. Carbohydrates, when consumed are converted into glucose for energy, but they release energy at different rates. Some are steady releasers and these are the best carbohydrates for our bodies to function at their peak. Other carbohydrates release energy too quickly; they boost our blood sugar levels but then like sugary foods, cause it to then fall rapidly.
The rate at which carbohydrates are converted into glucose is called the glycaemic index, abbreviated to Gi. The Gi uses a scale of 1-100, with pure glucose at the top with 100 and ????? at the bottom with 1. All the foods that have a Gi of 50 or more are considered high and contribute to weight gain as when these are consumed they reduce your blood sugar level by releasing the fat-storing hormone insulin. The energy is stored in muscles for short-term usage. When there is too much to store, typical with high Gi carbohydrates, the excess is turned into fat.
Generally, in Britain, 75% of our diet is composed of over-processed (refined) high Gi carbohydrates. Consuming these can actually make us hungrier as they raise blood sugar but then it falls rapidly; typically a white-bread sandwich has the same impact on blood sugar levels as a mars bar. Conversely, choosing low Gi foods makes the feeling of being full last longer and reduces food cravings. Syndrome X is caused by consuming too many refined carbohydrates. Syndrome X is an insulin resistance; linked to permanent obesity and diabetes. The overloading of these foods saturates the system with insulin and the body stops being able to respond to it. Less glucose is used as energy and more is converted into fat.
Calories are, of course, also important in a determining weight or gaining energy, but the important of carbohydrate energy conversion is as important, along with the saturated fat content of food. The British Dietetic Association places calories as the most important factor in weight change, but some now refute this, claiming that the glycaemic index of foods is more important a factor.
In general the less a Gi number the better for maintaining a healthy and low weight diet. Moderation is again the key. The Gi rating is the same regardless of the amount consumed.
Some examples of the Gi of foods:
Gi Food alphabetically | Gi from 100 to 1
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Last Updated: 28th July 2003