If you are a diabetic or a dieter trying to lose weight, keep your blood glucose levels low and stable. You may know that a diet in whole grains is "good" for you and that whole grain foods are rich in vitamins, minerals and fiber. Although grains encompass a variety of foods made from wheat, rice, oats, cornmeal and barley, they are all considered a carbohydrate source. Even though grains are nutritious, you may wonder how these foods affect your blood sugar.
Glycemic Index
The glycemic index ranks food and beverage based on how they are likely to affect your blood sugar. Foods with high rankings, 70 and over, are considered "high GI" foods that will significantly and rapidly raise your blood sugar levels. Foods with low rankings, 55 and below, are considered "low GI" foods that will not have significant or quick effect on your blood sugar levels.
Glycemic Index for Grains
Since "grains" refer to several different foods, there are several different rankings for each individual grain food. Registered Dietitian, Sandra Woodruff, at Florida State University explains that the more processed or refined a carbohydrate source is, the higher the GI score and more significant effect it will have on your blood sugar. Processed breakfast cereals and short-grain "sticky" white rice are examples of a high GI grain foods. Lower GI grains include long-grain brown rice, thick-cut oatmeal, barley and bulgar wheat. Generally speaking, refined "white" grain foods will have a higher glycemic index ranking than brown "whole" or long grain foods.
Specific GI Rankings
Harvard Medical School states the glycemic index rankings of several grain foods and their often higher-GI alternatives. Barley is the lowest of all the whole grain foods with a glycemic index ranking of 25, plus or minus 1. White rice is 64, plus or minus 7. Brown rice is 55, plus or minus 5. White bread scores a 73, plus or minus 2, while 100 percent whole grain bread scores a 51, plus or minus 11. Oatmeal scores a 58, plus or minus 4, while instant oatmeal scores a 66, plus or minus 1. The grain foods that have the greatest amounts of dietary fiber also have lower glycemic index rankings. This is because soluble fiber helps prevents glucose from getting absorbed into your bloodstream.
Weight Loss
Many people are interested in the glycemic index because they want to know which foods have the lowest GI rankings and which foods to avoid that have the highest GI rankings. While keeping your blood sugar low and stable will certainly help you lose weight, registered dietitian Sandra Woodruff explains that you first need to consider a food's caloric content to decide which foods will best support your weight loss goals. Although whole grain foods tend have higher glycemic index rankings than some protein-based foods such as red meat or regular cheese, whole grains are far more ideal for your weight loss diet because they are significantly lower in calories. The glycemic index is a good tool to use to compare carbohydrates, but reducing your weight loss efforts are primarily dependent on your caloric intake.
