GI stands for the Glycemic Index, which measures how quickly carbohydrates are digested and their sugars released into the blood stream. It's not just a fad diet, and many people are losing weight following the GI Diet. With any diet it is easy to lose focus whether you are new to the diet or have been following it for some time. Keeping a diet journal will help you to keep focused and will provide you with valuable information about works well for you.