Focus on Diabetes Health: Types of diabetes (Part 2)By: Michael K. Laidlaw, MD
Michael K. Laidlaw, MD, is a Rocklin physician specializing in endocrinology, diabetes and metabolism.
In our last article, we discussed the fundamentals of type 1 diabetes. Recall that our patient, HM, is a 38-year-old man who had three weeks of frequent urination and excessive thirst, as well as a 15-pound weight loss. He was seen in the emergency room and told that his blood glucose was 440.
Diabetes may be simply defined as a high blood glucose (commonly called sugar) level. A blood glucose of over 200 when checked at any time of the day is diabetes. The glucose test should generally be repeated for confirmation. We know that HM has diabetes. Is it type 1 or 2 or some other type?
Type 2 diabetes
As discussed previously, type 1 diabetes is characterized by the inability of the pancreas to produce insulin. Insulin is required to move glucose from the bloodstream into various cells of the body: muscle, skin, fat, and so on. If a person cannot make any insulin, glucose will remain in the blood stream and very high glucose levels result.
What about type 2 diabetes? Although many type 2 patients cannot produce normal levels of insulin, the more fundamental problem is something called insulin resistance. To use an analogy, let’s say that the cell has a door that allows glucose to enter. A key, insulin, is necessary to open the door and allow glucose to flow inside. Insulin resistance in this case is akin to the lock being jammed. Therefore, a greater amount of force must be applied to twist the key and unlock the door. In fact, before diabetes ensues, a patient may make higher amounts of insulin than normal. If the doors cannot be opened, then glucose remains in the bloodstream, resulting in high blood glucose levels.
What is the cause of insulin resistance? There are many factors being investigated, but the biggest problem appears to be fat, particularly visceral fat. Visceral fat is a type of "belly fat" that surrounds the organs in our abdomen. Fat tissue appears to produce factors that essentially jam up all of the locks of the body's cells, therefore not allowing insulin to do its job. As a consequence, the pancreas works very hard to produce insulin to overcome this effect and "burnout" occurs. The cells of the pancreas actually die in the process of trying to overcome the resistance. The diabetes problem is now compounded by both a lack of insulin as well as insulin resistance.
Can the changes described be stopped or reversed? The short answer is "yes," in my opinion. Through a good diet, which consists of a moderate carbohydrate intake along with very low sugar, I have seen patients stop or even reverse the progression of type 2 diabetes (more on this in future articles). So does HM have type 1 or 2 diabetes? Part 3 of this series will answer this question, along with discussing other less common causes of diabetes. For now, thanks for reading and stay tuned.