All forms of carbohydrates must be converted into glucose (blood sugar) before it can be carried in the blood for utilization by the body. Pure glucose enters the bloodstream very fast since it doesn't have to be converted. This results in a quick rise of blood sugar and the body release insulin to stabilize the blood sugar levels. For a short period you will feel energetic and focused. The result of this, however, will be a drop in blood sugar to a level below what you had before you consumed the drink. You will feel tired and unfocused.Insulin is also known for its abilities to stop your fat metabolism. So, if you want to loose weight stay away from high blood sugar! Usually, there shouldn't be a problem with only one can. But if you drink a lot of cans after each other or if you use a brand that has much glucose there might be problems. It's usually better to choose a product containing fructose instead of glucose. Fructose will not affect your blood sugar in the same degree.