Researchers say the slower the digestion of carbohydrates, the slower the increase in blood sugar. Less insulin is needed - leading to a gradual drop in blood sugar. The result: less hunger at your next meal. It's called the Glycemic Index. Know it.

The Secret to Your Weight Loss Success Could Lie in the Glycemic Index

The gylcemic index or GI is a measurement of how fast a food with carbohydrates will make your blood sugar levels raise. Now that we have moved past the philosophy that all carbs are bad and we understand that carbohydrates are a necessary, vital part of our nutritional needs we can assess which are best.  The standard against which all foods are measured in the index is glucose, which will increase your blood sugar by 100 percent in two hours. So glucose is given a numerical value of 100.  The range is as follows: a high GI is 70 and above, a medium GI is between 56 and 69, and a low GI is 55 and below.
To give you an idea, here is a short list of common foods and their GI.

Bakery Foods

Pound cake  54 Low

Doughnut 76 High

Beverages

Soya Milk 30 Low
Orange Juice 52 Low

Breads

Multi Grain  48  Low
Baguette 95  High

Cereals

All Bran 42 Low
Corn Flakes 83 High

Fruits

Cherries 22 Low
Pineapple 66  Medium
Watermelon 72 High

Root Crop

Carrots  39 Low
Potato  83 High

Snack Foods

Peanuts 15  Low
Dates  103 High

The theory is that when you eat a high GI food, it raises blood sugar levels quickly, which triggers the pancreas to release the hormone insulin. This, in turn, lowers blood sugar levels just as quickly, which activates the hunger response.

Studies have been conducted testing the different effects of different levels of GI number breakfasts.  In one study, three groups were created and given different breakfasts each with the same number of calories but with different GI’s. Group 1 had a low-GI breakfast of fruit and omelets, group 2 had a medium-GI breakfast of steel-cut oats, and group 3 had a high-GI breakfast of instant oatmeal. Each group’s lunch appetite was then measured and the results were consistent with the GI rationale. The group who ate the high-GI breakfast of instant oatmeal ate twice as much as the boys who ate the fruit and omelets.

The researchers concluded the slower the digestion of carbohydrates, the slower the increase in blood sugar. This means that less insulin is needed, which in turn means that, later, there will be a gradual instead of a sharp drop in blood sugar and there will be less hunger at your next meal.  The less hungry you are, the less food you will want and the more in control of your appetite you will be.

Wow, that’s it; the secret to eating right has been discovered. We should all now be able to get into shape, right?  No, there is another component to the diet puzzle. The GI is not a perfect guide to choosing healthy carbohydrates. Here's what you need to know about the GI to get a more complete picture.

The GI tells you how fast the carbohydrates in a particular type of food will turn into sugar, but it doesn't tell you how many carbohydrates or calories per average real-life serving the food contains.  It's important to know both. Otherwise, you might think that watermelon should be avoided because it has a GI of 72.

The glycemic load (GL) is the counterpart to the equation. The term was coined by Dr. Walter Willet of the Harvard School of Medicine together with Dr. Jenny Brand-Miller of the University of Sydney, who is one of the foremost authorities on the GI.
The GL takes into account how many carbohydrates there are in a serving of a particular food, not just how fast the carbs turn into sugar. It uses a different rating than the GI. A GL of 20 or more is high, a GL of 11-19 is medium, and a GL of 10 or less is low.

Bakery Foods

Banana Cake  18 Medium
White Bagel  25 High

Beverages

Tomato Juice  4 Low
Coca Cola  15 Medium

Cereal

All Bran  4 Low
Cream of Wheat 22 High

Fruits

Watermelon  4 Low  
Dates   42 High

A watermelon is mostly water and foods high in water will not cause sharp increases in blood sugar.  So one serving doesn't contain as many carbohydrates as a serving of potato, which is mostly starch. Thus, a watermelon has a GI of 72 but a GL of 4, while a baked potato has a GI of 85 and a GL of 26.

High-calorie foods that contain fat and protein as well as carbohydrates can rank lower than low-calorie foods that do not contain as much fat or protein. This is because fat and protein slow down the effect that carbohydrates have on blood sugar.  For example, a reduced fat yogurt has a GL of 7 while full fat ice cream has a GL of 4. 

Always remember that when it comes to weight loss, calories still count. Select carbohydrate foods based not just on their GI rating but also on the basis of their health benefits.  White rice has a GI of 56 while brown rice is 55. If you use only the GI to choose between the two, there is hardly a difference. But brown rice has more fiber and nutrients compared to white rice. Also, brown rice will make you full faster than white rice will.

Use the GI, the GL, the Food Pyramid and your basic intuition to judge what is good for you and which choices make most sense.  Look for foods that will fill you up, provide nutrients, are low in trans-fats and if all else fails; look them up online until it becomes standard knowledge for you.

By Christina Leon, Staff Writer