blood glucose goes up, this induces insulin secretion from the pancreas, the insulin in turn will take the calories (glucose and fatty acid) from our bloodstream and store them in our fat tissues. The calories are not available anymore to fuel our daily activities, they are blocked by insulin. As a result, without adequate energy, we feel tired and hungry. We sit down in front of the TV and eat.
Under normal circumstances, when we consume a carbohydrate rich meal, insulin is secreted in two waves from the pancreas to do the job of glucose disposal:
- The first wave is secreted well before sugar (glucose) enters our bloodstream. The role of insulin is very important, it prepares the body for what might come next: a big meal, when it is necessary to remove the glucose from the bloodstream. This wave begins with the mere taste of food. In some individuals, it occurs even at the sight or the thought of a palatable food.
- After consuming our meal high in carbohydrates, a second wave is secreted. The high blood glucose signals to the pancreas to release more insulin, even though there is already enough insulin in the bloodstream from the first wave. "The pancreas has no idea what is going on elsewhere in the body. All it sees is the glucose." (Gerald Grodsky - University of California, San Francisco).
After a Diet Coke, the first wave of insulin still occurs. A second wave of insulin will not be secreted, because of lack of glucose in this drink. If after a Diet Coke, we consume a high carbohydrate diet, we end up with 3 insulin waves: one from the Diet Coke and two from the meal.
Does Diet Coke make us lean? I don't think so. It just adds more insulin to our already high insulin levels from a carbohydrate rich diet.
The best way to ameliorate high insulin levels (hyperinsulinemia) is to avoid easily digestible carbohydrates and sugar. On a low carbohydrate diet, insulin levels are reduced and we have less cravings for carbohydrates and more energy available. Appetite normalizes.