I have been hearing a lot about this new idea of someone being insulin resistant. Along with this people are saying that they are “addicted” to carbohydrates and are therefore cutting them out of their diet. This does not make sense to me. I have had diabetes for 7 years and am wondering if there is any truth to these ideas.

For decades, there have been arguments as to what is the best diet for people with diabetes (and it may not be the same for Type 1 and Type 2 diabetes.) When insulin first came out, it was recommended that people with Type 1 diabetes eat a very low carbohydrate, high fat diet as it was understood that carbohydrates increase the blood sugar the most and the fastest. It was felt if you limit the carbohydrates and make up your caloric needs with protein and fat, you could better match your insulin to your food with less insulin. In the past decade, there has been a trend towards allowing more carbohydrates and more concentrated carbohydrates as long as you “counted the carbohydrates” and tried to match your insulin to the amount of carbohydrates you eat. With the advent of the faster acting insulin, Humalog, this became more feasible, but still not always perfect. Although Humalog works quickly, people with Type 1 diabetes are still deficient in another hormone, amylin, which is also made by the pancreas, and which can slow the absorption of food from the gastrointestinal tract. Keep in mind, as insulin levels go up in the blood (either from insulin injected or made by the body), at a certain point, you don’t get much more insulin action as the body becomes resistant to large amounts of insulin. Therefore, at some point, it becomes hard to match your insulin to high carbohydrate intake. Fat and protein eaten with carbohydrate slows the absorption of food from the gastrointestinal tract. People with Type 1 diabetes often put on extra weight when they try hard to keep their blood sugars normal. Increasing the fat in the diet and decreasing carbohydrate intake may help avoid increases in blood sugar after you eat. If you need less insulin with a lower carbohydrate diet, you may not put on as much weight (assuming the total calories are not increased).

In Type 2 diabetes, where the primary problem is insulin resistance (and many overweight individuals with Type 2 diabetes make more insulin than normal weight non-diabetic individuals), anything that promotes weight loss will improve blood sugar. One can lower fat intake, carbohydrate intake, protein intake, or all the above and blood sugars may improve if the person loses weight. For the same amount of calories, you theoretically need to make more insulin to keep the blood sugar normal if the food is higher in carbohydrate than fat. Insulin can increase the appetite and promote further weight gain.

Some people are recommending an extremely low carbohydrate diet to minimize insulin requirements and weight gain and maximize blood sugars. It is not clear whether the high protein and fat content of these diets has other adverse effects on lipids and kidney function in the long term. There are no good studies that I know comparing these very low carbohydrate diets to higher carbohydrate diets.

Somehow, I always come back to my “gut feeling” that a well balanced diet avoiding extremes of either very high or very low carbohydrates is probably the most realistic approach for most people until we have more data.

TGL