Proper diet is crucial for diabetics, as food can have both short and long term effects on blood glucose control. For reasons researchers have yet to uncover, blood sugar levels soar after eating, and many diabetics need to time their insulin injections around meal times to aid in controlling blood sugar. One thing researchers do know – the higher the glycemic index of a food, the more impact it has on blood glucose.
The glycemic index (GI) is a measure of the influence that a particular food has on blood sugar levels. It takes into account the fact that different types of carbohydrates perform differently in our bodies. The GI ranks carbohydrates on a scale of 1 to 100 based on how quickly they raise blood sugar.
Low GI foods are in the range of 0 to 55, medium are ranked 56 to 69, and high are scored 70 and above. Foods with a high GI are rapidly digested and absorbed, resulting in a rapid spike in blood sugar and insulin demand. Foods with a low GI are digested and absorbed more slowly, resulting in a more gradual increase in blood sugar and insulin. Because they’re digested more gradually, low GI foods reduce hunger and keep you feeling full longer.
In general, the more fiber a food has, the lower its GI. Whole grains like oats, barley and bran, nuts, eggs, milk, meat, legumes, fructose, most fruits and vegetables, and low carbohydrate foods are low on the GI. Whole wheat products, basmati rice sweet potatoes and sucrose rank medium on the GI. Most high carbohydrate foods like potatoes, watermelon, white bread, white rice, candy, pastries, most baked goods, low fiber breakfast cereals and glucose are all high on the glycemic index. The resourceful Australians have developed a low GI potato called “Carisma”, but sadly, it’s not yet available in North America.
A low GI diet reduces the body’s insulin levels and insulin resistance, and improves overall blood glucose control in both type 1 and type 1 diabetics. As a rule, diabetics are advised to eat foods that are low to medium on the GI, but a diabetic who is experiencing a period of low blood sugar may want to eat a high GI food to quickly raise their blood sugar. You can use a glycemic index chart to search for low glycemic food choices, and to check the glycemic index of your favorite foods. Bear in mind that other factors will affect the impact a food has on blood sugar, such as fat and protein content, ripeness, cooking method, the combination of foods eaten, the time of day, and your insulin and activity levels.
Recent studies indicate that the risk of diabetes and other diseases is closely related to the overall GI of our diets. A US study of national data spanning almost 90 years found that the rising consumption of high GI corn syrup (widely used to sweeten soft drinks and processed foods) and decreasing intake of dietary fiber parallels the explosion of type 2 diabetes in America. The World Health Organization recommends a low GI diet to prevent and combat the “diseases of affluence” that are rampant in North America – diabetes, obesity and heart disease.