Ask the experts
I have a friend that is 35 and has diabetes. For the past eight years, his weight has always been in check and if anything he may have been a little overweight. Just recently, he has lost a lot of weight and he told me that he weighs less than he did in high school. I think he looks too thin and I am concerned about his health with him being a diabetic. Should there be a concern and what kind of advice can you give me to pass on to him.
We often assume weight loss is good and healthy. A slow steady intentional weight loss using nutritional change and exercise is associated with beneficial effects on the heart, blood pressure, and cholesterol levels. In addition, weight loss can reduce "insulin resistance" and make muscles and fat tissues more sensitive to circulating insulin levels in the blood.
What type of diabetes causes weight loss?
A reduction in insulin resistance is problematic because insulin is needed to help glucose enter these tissues to be metabolized. If these tissues are resistant to insulin, higher than normal levels are needed for this process to occur. This is often the case in Type 2 diabetes. As a result, a vicious cycle occurs, the higher the insulin levels are, the harder it is to lose weight (insulin is anabolic, and is a hormone that likes to store fat). On the other hand, the heavier a person is, the more likely they are to have higher insulin levels. As you can see, the cycle is often hard to break.
What causes unintentional weight loss in diabetes?
While intentional weight loss in people with diabetes is usually a good thing, unintentional weight loss is not. If blood sugars are very high, patients with diabetes tend to urinate a lot, and this results in dehydration as a possible cause of weight loss. Also, muscle breakdown can occur if sugars are too high, causing an unhealthy weight loss. Actually, many patients with diabetes present for the first time to their doctor's office because of unexplained loss of weight. In addition to diabetes, there are other concerning causes of unexpected weight loss which should be explored such as thyroid disease and cancers.
In summary, a supervised attempt to lose weight in people who can exercise without risk is usually of benefit. However in certain cases such as if blood sugars are too high or too low or if heart disease is present, it can be dangerous. This is why all exercise and weight loss programs should be started only after discussion with a physician. Any unexplained weight loss, in patients with or without known diabetes may be a sign of high blood sugars or another serious illness. It is absolutely necessary to see a physician and undergo a complete evaluation in these cases.
Medically reviewed by John A. Daller, MD; American Board of Surgery with subspecialty certification in surgical critical care
Fauci, Anthony S., et al. Harrison's Principles of Internal Medicine. 17th ed. United States: McGraw-Hill Professional, 2008.