GI stands for glycemic index, and is a measurement of the amount a food raises blood sugar levels after it has been consumed. The scale is between 0 and 100, with glucose being a reference point with a score of 100 on the scale. Foods that have a high GI rating are foods that cause sharp increases in blood sugar levels after the food is consumed. These spikes usually lead to sharp drops in blood sugar level, which causes energy crashes and hunger cravings.
In contrast, foods with a low GI score cause a slow increase in blood sugar levels, allowing the body to process the sugar slowly. There is no large drop in blood sugar or energy levels as the sugar is processed and removed from the blood stream, and so hunger cravings are fewer and satiety levels are perceived as higher.
So What is The GI Diet Itself?
The idea is to eat primarily low gi foods and to limit the amount of high gi foods that are eaten. For people with diabetes, with will lead to a lowering of their blood sugar levels, which is better for overall health. For people who are trying to lose weight, limiting the intake of high GI foods will stop sugar crashes following their consumption, and will mean that there are less cravings for snacks in between meals. Choosing low GI foods instead will leave the dieter satiated for longer, again leaving them less likely to snack and more likely to find success with their diet.
The Glycemic Index only covers foods that are carbohydrate based, but the diet does not exclude other food groups. High GI foods are those that have a GI score of 70 or above, and include white rice, white bread, pretzels, white bagels, white baked potatoes, crackers and sugar-sweetened beverages. These foods should be removed from the diet as far as possible. Medium GI foods, which have a GI score of between 56 and 69, can be eaten in moderation. These include bananas, grapes, spaghetti, ice cream, raisins and corn on the cob.
Finally, low GI foods have a GI score of 55 and under, and should be the main source of carbohydrate when following a GI diet. These foods include oatmeal, peanuts, peas, carrots, kidney beans, hummus, skim milk, as wells as most fruits, except those listed above and watermelon. A general overview of the GI rating of many foods is available here.
Generally, choosing a whole grain option of a food over the white, bleached version will be beneficial, as whole grain options typically have a lower GI score than their equivalent products.
Research Supporting GI Diet
There is some preliminary research to support the GI diet. One study showed that people on a low-glycemic diet lost more fat than those on a high-glycemic diet with the same calories. This was a preliminary study, but the results are promising. If the dieter were able to reduce their calorie intake because of increased satiety, the weight loss results would be even more pronounced in comparison to a high GI diet. Research also shows a link between a low GI diet and improved levels of good cholesterol.
Combining Other diets
It is possible to combine diets easily with the GI diet. Because it does not dictate what meals should be eaten, but only recommend food choices, it is versatile and can be made to be suitable for vegetarians or vegans. Similarly, it can be combined with other diet plans such as weight watchers, slimfast or calorie controlled diets. This is because both the GI diet and many calorie controlled diets do not use specific meal plans as a part of the diet, allowing dieters to make their own choices about the foods they eat.
The GI diet has also inspired other diets, especially diets that restrict carbohydrate intake. The Mayo Clinic credits the GI diet for inspiring the Zone diet, Sugarbusters and Nutrisystem. These diets have more clearly laid out rules and restrictions than the GI diet, and they may be a viable option to dieters who desire more focus and less freedom from their weight loss diet.
Flaws with the GI diet
Because the GI diet only provides guidelines about one type of food, carbohydrate, and is based upon one very specific measurement, the diet does have some flaws. There are some processed and unhealthy foods that rank fairly low on the Glycemic Index, and so it is possible to eat only low GI foods whilst still eating an unhealthy diet. As this is not the goal, it is advised that dieters use some common sense when consulting any GI chart, and choose foods that are both low GI and healthy in general.
The Gylcemic index system is also a slight oversimplification of the way that food affects glucose levels in the blood. Combining different food groups changes the way that food interacts with the body, and can increase or even lower the GI ratings of individual carbohydrate foods. Followers of the GI diet need to remember that the GI rating of an ingredient is not the only consideration to make when planning meals.
Following the diet does also take some practice. Food packaging generally does not market the GI rating of the food, or if it does, it generally states whether it is High, Medium or Low on the GI scale. Shopping with a GI diet in mind can therefore be confusing and difficult initially. It is recommended that dieters take a copy of a Glycemic Index with them when grocery shopping.
Our Verdict on The GI Diet
The GI diet was originally a diet developed to help to control or prevent diabetes by preventing large sugar spikes in the blood stream, which can lead to insulin resistance. Therefore, this diet is clearly beneficial, not only in terms of potential weight loss, but also for the dieter’s health in general.
Choosing low GI foods over high GI options is a viable lifestyle choice which can be followed in the long term, even when weight loss is not a consideration of the individual. Dieters should use common sense when making food choices, and limit portions, as well as choosing healthy low GI options. As no foods are totally restricted, the GI diet offers freedom and choice to people who want to change their diet to benefit both their health and their waistline.