Glycemic Index Guide
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Glycemic Index Food Rating System
What is the glycemic index and why is it important?
I started down this journey 15 years ago but by now most have probably heard of the glycemic index. It is extremely important to many people who want to lose weight, have diabetes, or many other health conditions like high cholesterol or high blood pressure. It is even important for many other conditions. This is probably the most complete and FREE guide to glycemic index foods and eating guidelines available. Feel free to copy this or pass it around as you desire.
The glycemic index is a relative measure of how fast food gets converted into glucose sugar and delivered to the blood stream. Typically this absorption will take place over a two or three hour period. How fast and how much sugar is delivered usually indicates how much insulin will be produced. Too much insulin causes many bad biochemical reactions and can lead to weight gain and serious illnesses and degenerative diseases. The index value is set based on the amount of sugar produced over time compared to a standard food like white bread. The standard food sets the value of 100 for the glycemic index. Some glycemic values use glucose sugar as the 100 standard setting value. I am using white bread here as the 100 glycemic index standard.
The glycemic index is not perfect as an insulin creator indicator but it is the best indicator we have found so far. Many factors influence the glycemic index (GI) and can cause variations between individuals and ethnic groups. The values given here are a good general indicator and guideline but the values are not to be considered absolutely correct at all times. The charts presented here more importantly give an indication of relative values. Is this food high, medium, or low. The quantity of food you eat at one time affects the amount of insulin produced. If you eat a very small amount of high GI food it will probably cause less insulin reaction than eating a very large amount of medium GI foods. This does not mean that you should eat high GI foods on a regular basis. It instead means that it is best to eat small quantities of food many times a day and never eat most of your calories in one large evening meal.
The glycemic index dispels the myth that all sugars are bad and all complex carbohydrates are good for you. We see from the charts that many complex carbohydrates are worse for you than pure sugar.
The glycemic index of an individual food item is not as important as the sum of the indexes of all of the food and drink you consume at one time. This is called the caloric weighted glycemic sum. It is computed by adding the sum of the calories and GI for each food item. If you eat fewer calories of an item it will have less influence on the final average of caloric weighted glycemic indexes. This can get a little complicated unless you like doing math in your head. Just remember to always eat a substantial amount of low glycemic foods to mix with your higher GI foods. For example 8 oz. of baked potato (very high), 4 oz. of steak (very low), and 4 oz. of cooked carrots (very high) would give you a high glycemic sum. It would be better to have 4 oz. of boiled potatoes (high, but not as high as baked), 8 oz. of steak (very low), and 4 oz. of green beans (low). The first example would end up with an average GI of about 90 (high - same GI as pure table sugar), while the second example would end up with an average GI of about 45 (medium low).
Factors that influence the Glycemic Index
1. Amount of protein and fat in a food. More protein and/or fats and less carbohydrates leads to a lower GI value.
2. Fiber content, in particular soluble fiber content. There are two types of fiber – soluble and insoluble. Insoluble fiber common in most grains, wheat and rice, does not seem to influence the glycemic index. Soluble fiber, from oats, fruits, and vegetables reduces the GI.
3. Degree of food processing. Instant foods are always much higher. The closer food is to its natural state the lower the GI. Heating also raises the GI.
4. Food form. Powdered, ground, or liquid foods tend to be higher than coarser solid forms. Puffed foods, like popcorn and puffed rice, usually have a very high GI.
5. Amount of sodium and potassium. These elements are needed for digestion and if they are present in the food it may speed up the conversion to sugar and raise the GI.
6. Ripeness or maturity of food. Ripeness generally raises the GI.
7. The nature of the starch in a food. Foods contain different starches and sugars naturally and they effect the glycemic index.
8. Enzyme content of food. High amounts of amylase enzyme which is used to digest carbohydrates can quicken the conversion process and raise the GI.
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