American Society For Nutrition

The Perverse Logic in Treating a Type 2 Diabetic with a High Carbohydrate Diet

The Perverse Logic in Treating a Type 2 Diabetic with a High Carbohydrate Diet

Excellence in Nutrition Research and Practice
Posted on 10/09/2013 at 02:33:58 PM by Student Blogger
By Larry Istrail, MS

"When you're a hammer, everything looks like a nail." Nowhere is this statement more true than in medicine.  A perfect example is in the treatment of type 2 diabetes.

If a doctor suspects his patient may be diabetic, he can run an oral glucose tolerance test (OGTT), in which the patient is given a glucose load, and subsequent blood response is measured to see how effectively the glucose is cleared from the bloodstream. In a non-diabetic patient, the blood sugar only rises a relatively small amount, as the intact and functional beta cells of the pancreas secrete just the right amount of insulin to reduce the blood sugar levels back to normal.

If a patient is given an OGTT and the blood sugar spikes more than expected, then by definition they are glucose intolerant. They have failed their OGTT, and cannot tolerate carbohydrates the way a non-diabetic can.

In medical school, we are taught that the primary goal in treating diabetics is to keep blood sugar levels low, and that hemoglobin A1c levels are predictors of further disease progression. There are two major ways to control this blood glucose level: with what we put into our bodies, as well how we mitigate the hyperglycemia once it has occurred.
Alpha-glucosidase inhibitors are a category of drug that work by decreasing the absorption of carbohydrates in your gut, resulting in a smaller rise in blood glucose. However, the unabsorbed carbohydrates need to go somewhere, causing the predicted unpleasant side effects of stomach discomfort and diarrhea.

Now instead of taking a drug that will reduce our absorption of carbohydrates, result in various side effects and cost additional money, why not just eat less of the very foods spiking the blood sugar in the first place? In other words, why would the American Diabetes Association (ADA) tell us that a diabetic diet should be 40-50% of the calories from carbohydrates, when by definition, these are the very foods they cannot tolerate? Visit the link to see how the ADA describes it on their meal-planning page: “How Much Carb?" It says: A place to start is at about 45-60 grams of carbohydrate at a meal.

It seems equivalent to a person with a peanut allergy slightly lowering their peanut intake and just injecting him or herself with an epinephrine pen after each meal. Why not just stop eating peanuts and avoid the side effects and discomfort of epi injections? Why don't they just eat less of the instigating carbohydrates in the first place? After all this was the treatment of diabetes in the pre-insulin era. Here is how Dr. Elliot Proctor Joslin described it in 1893:

Diabetic treatment is of the first importance. The carbohydrates taken in the food are of no use to the body and must be removed by the kidneys thereby entailing polydipsia, polyuria, pruritis and renal disease…The beneficial effects [of removing carbohydrates] were seen at once, and [Dr Joslin's patient] was advised to “eat all the cream, butter and fatty foods possible.

120 years later, the Joslin Diabetes Center, named after Dr. Joslin above, has a different message: Starchy foods, such as bread, pasta, rice and cereal, provide carbohydrate, the body's energy source. Fruit, milk, yogurt and desserts contain carbohydrate as well. Everyone needs some carbohydrate in their diet, even people with diabetes... [diabetics should consume] 40 percent [of calories] from carbohydrates.     

Diabetes is diagnosed by demonstrating a glucose intolerance and therefore the first line of therapy should be a reduction in glucose. Why is this logic not the first, most obvious treatment? Of course if the patient refuses, or they reduce their carbohydrates and their blood glucose levels continue to remain elevated, then further therapy is in order.

Regardless of the etiology of each patient's food related disease, his or her treatment is seen as a constant, unchangeable variable given the label of "diet" or "lifestyle," which is invariably some variation of a low-fat, high carbohydrate diet. Just the fact that alpha-glucosidase inhibitors are used as a treatment for diabetes before a low carbohydrate diet confirms this.

Furthermore, if the patient is given a low-fat high carbohydrate diet (as is the standard of care today) to manage high blood sugar and he/she does comply with it meticulously, they will very likely need the insulin, alpha-glucosidase inhibitors, and/or metformin to control their daily dose of 180 grams of the very nutrient they cannot tolerate.





3 Comments
Posted Oct 18, 2013 4:23 PM by charity

An interesting topic and worthy of looking into. However, I would say that the ADA has some pretty good reasons to suggest that diet be a minimum of 40% carb-based. We get energy and nutrients from carb based food. So, while reducing carbs may help reduce blood sugar levels, individuals may not be getting enough nutrients and energy if their carb load is reduced.


I imagine the pertinent followup question relates to dosage: do you suggest patients enter a state of ketosis for therapy?

Eating a diet that has a collectively low glycemic load can still incorporate carbohydrates and be therapeutic for the patient. Is that 40% of carbohydrates coming from white bread or carrots needs to be taken into account in the recommendations - just saying carbohydrates isn't addressing the issue of glycemic response.


Very interesting, My whole family suffers from diabetes and it runs genetically. Will let them read this article. Please post more. Great job!