If you do much reading about diets or nutrition, you likely will come across the term “glycemic index”. It’s a term used more and more, so today we present an overview so you will better understand the concepts involved.
What is Glycemic Index? : It is a way to measure or rank foods based on how quickly, once you eat them, they are converted into glucose (sugar) in your system. Foods receive a glycemic index (GI) score from 0 to 100. Glucose scores 100, the highest possible. The basic idea is that the lower the score of a particular carbohydrate food, the healthier that food is for your body.
Only foods containing carbohydrates are ranked, so items like meat, fish, and chicken do not have GI scores.
How is GI determined? Experiments are carried out on people to determine the GI for each food. After an overnight fast, research subjects are fed a fixed amount of a food and their blood glucose is measured at fixed intervals. It is an expensive and elaborate process (many people must be tested for each food), and many foods have not yet been tested for their GI score.
Is GI a type of diet? GI is not a specific diet, but many modern diet plans are based at least partially on the GI concept, such as the Zone, South Beach, and Nutrisystem diets.
What is the benefit of eating low GI foods? When you eat carbohydrates, your stomach and intestinal enzymes digest (break apart) the carbohydrates and they are converted into glucose. Glucose is the most simple (and usable) sugar of all carbohydrates.
Once the carbohydrates are converted into glucose, the body can use that as fuel to keep all your bodily processes going. If you think of your body as a car, the gasoline is glucose.
Foods with high GI scores are converted very quickly from carbohydrates into glucose. This produces a quick surge in the level of the glucose in your body. It’s a lot all at once and your pancreas (which makes the hormone insulin) needs to rapidly produce and pump out lots of insulin, which chemically forces the glucose from the bloodstream into the individual cells where it is needed.
If you eat lots of foods with high GI, your body will frequently be flooded with high levels of glucose—too much really, and eventually your body may become resistant to the effects of insulin, resulting in your sugar level staying too high. Diabetes and and other metabolic problems can arise, such as high blood pressure and severe obesity. High chronic glucose and insulin levels are felt to especially lead to more fat accumulating in the deep abdominal areas, around our vital organs.
But what is the real benefit of a LOW GI diet? If most of your carbohydrate intake is from LOW GI foods…such as most fruits, oatmeal, pasta, and legumes…these things are slowly digested, so you will have a nice SLOW release of glucose into your system. Your pancreas doesn’t need to pump out such high levels of insulin, and over the years, you are less likely to “wear out” your pancreas, and you avoid developing diabetes.
The GI Index of foods contains many surprises. For example, some starchy foods like white potatoes or white bread have higher GI scores (worse for you) than honey or table sugar.
Next post we will present a list of foods with their GI scores, mention the GI controversies, and finish with some hints.
Esta postagem também está disponível em: Portuguese (Brazil)