Although the health implications of diabetes are clear, researchers are still struggling to understand many of the aspects of the disease.
One question being asked is why most people with type 2 diabetes are overweight or obese, when most overweight or obese people are not diabetics?
The fat cells themselves may offer a clue. These cells release triglycerides and free fatty acids into the blood, which may decrease cells ability to respond to insulin, thereby increasing the body’s demand for the hormone. Paradoxically, another hormone, adiponectin, is also made by fat cells, and this hormone makes cells more responsive to insulin.
According to Dr. C. Ronald Kahn, a diabetes researcher and professor of medicine at Harvard Medical School, the fatter you are, the less adiponectin your fat cells produce. Therefore, one way obesity might increase your risk of developing diabetes is by an increased release of fatty acids, combined with a decline in adiponectin, which would lead to more insulin resistance. If your body’s demand for insulin cannot be met, diabetes eventually sets in.
Another question being pondered in scientific circles is why high blood sugar specifically leads to the disease’s other complications:
– Heart disease and stroke
– Nerve damage
– Kidney damage
– Sight-threatening eye damage
Theoretically, if your blood contains high levels of glucose, every cell in your body would be affected, yet only certain cells appear to be damaged, leading to the complications mentioned.
Scientists have discovered that the unscathed cells are those capable of keeping out excess glucose, by reducing the number of molecular glucose pumps they use to transport glucose from the blood to the interior of the cell.
Cells that are damaged lack this ability to compensate. They include cells lining the arterial blood vessels, small blood vessels in the eyes and kidney, nerve cells in the legs and feet, and pancreatic cells – exactly those involved in diabetic complications.
New York Times August 20, 2007