I must emphasise that the GI value of a food can be influenced by a variety of reasons. The amount of the food consumed and the time of the meal have a role to play.
Again,a particular variety of wheat or rice may have a GI value quite different from another variety,simply because of the character of the starches in them. If the food is cooked for longer,the GI value increase,which is why al dente pasta has a lower GI than the extra soft cooked one. Similarly,if a food is finely chopped or pureed,it will have a higher GI value.
The fat,fiber and protein content of the food also influence the GI. For instance,even if the sugar level in two samples of ice-cream is the same,the GI level will differ if they have different fat levels. The non-dietary factors that affect GI values include ones medication,stress,physical activity and the overall health status.
Another oft repeated question is related to whether non-diabetics should worry about spikes in blood sugar caused by high GI foods. A firm and clear answer is that they certainly should.
Whenever a high GI value food is consumed,there is a sharp rise in the blood sugar level that causes a surge in the insulin level to help the body process the sugar. The consequence of such a metabolic milieu predisposes one to insulin resistance,which in turn could lead to a number of problems.
A high level of insulin is not desirable for other reasons as well. Recent research seems to suggest that high insulin levels triggered by high GI foods could possibly increase the risk of certain degenerative diseases. In spite of the seemingly complex situation involved,it is worthwhile to use the GI of foods as a guide to food selection simply because of the many health benefits.
Here are simple rules to be followed to achieve low GI levels.
Consume less processed,less refined,whole grains as a general rule. Do add beans and lentils as a complement to most starchy foods. Include some raw vegetables and fruits in every meal to keep the balance in favor of low GI.
Try and cook foods only as much as necessary and avoid overcooking.
As a closing statement,I would advise people not to be overly concerned about the GI of foods that contribute less than five grams of carbohydrate in one serving. This applies to some nutritionally dense foods such as carrots that have a high GI but low amount of total carbohydrate in a serving.