The Glycemic Index: Things You Need to Know

A Doctor at the University of Toronto developed the glycemic index (note: this is sometimes spelled glycaemic) in the early 80’s. At first the index was utilized as a means for diabetics to gauge the insulin demand of the foods they ate. It wasn’t until later that dieticians realized the value of the index for non-diabetics in both losing weight and optimizing calorie intake. Understanding what this index is and why it is important is a necessary step in being able to use it to optimize your diet.

First of all it is important to understand exactly what the index measures. Though every food we eat is digested and absorbed into the bloodstream the rate at which this happens varies widely. Factors that can influence this rate of absorption vary widely from how they were grown and in what soil all the way to the type of starch and acidic content in the food. This is an important facet of the glycemic index that most people ignore. The tables showing the GI (common term for the Glycemic Index) of a food can be misleading unless the food is stored, cooked and processed in the same manner as the one listed on the index. Otherwise these other factors can greatly increase or reduce the glycemic index for that particular serving. Thus, the first important rule of utilizing the glycemic index is as follows:

RULE #1: Make sure the food you are eating is processed, cooked, stored and grown in the same manner as the food of the index you are using. Make sure you follow the guidelines outlined in the methodology of the index.

The second factor that is important to understand about the glycemic index is that the same food with all the same extraneous factors (those we discussed above) can have a dramatic difference in absorption rate depending on the individual. Therefore, we must understand that everybody is different and the ways in which the digestive system processes food varies according to the person. In fact, it is this particular point, which characterizes diabetes as well as hypoglycemia and its opposite hyperglycemia. Essentially all of these disorders characterize individuals who somehow process starches and sugars at a rate significantly lower or higher than the norm. Thus, this leads us to rule number two of utilizing the glycemic index:

RULE #2: Know your own body and how it responds to sugars and starches. A simple test by a Doctor or Dietician can help you understand this information and allow you to follow a diet recommended for your digestive system.

The two rules above are the most important for using the index to design a sound and healthy diet based on your particular needs. So now the question is how can the glycemic index help you?

To understand the benefits it is necessary to know how low GI the body utilizes low and high GI foods. Essentially, low GI foods are digested so that the starch and proteins are releases gradually over a period of time. Thus, these types of foods are recommended for diabetics and anyone expending moderate amounts of energy of an extended period of time. By converse, high GI foods release their starches and sugars very rapidly resulting in a dramatic increase in blood glucose levels. This is the effect, which many call a “sugar high”. These types of foods are appropriate for replenishing energy sources that have been expended or when the body is in need of rapid recovery. One important has been that those who follow low GI diets have a decreased risk of heart diseases and diabetes while those who follow a high GI diet have an increased risk of obesity in addition to those noted above.

There is one more important thing to know before utilizing the glycemic index in designing your diet, and that is exactly what the dividing line is between a low and high GI food as well as some noteworthy examples of each.

HIGH GI FOODSn(High GI is typically defined to be in excess of 70)
Bran FlakesnDates
Watermelo

Sweet Potato

LOW GI FOODSn(Low GI foods measure at 55 or lower)
Grape FruitnCherriesnApplesnPears
Skim MilkRay Kelly is the Personal Trainer that guided Adro Sarnelli to his win on The Biggest Loser Australia. Visit his websites at http://www.free-online-health.com/australias-biggest-loser.htm and http://www.raykellyfitness.com