How insulin resistance leads to diabetes
Diabetes is a simple disease. It occurs when your pancreas is unable to produce enough insulin to keep glucose under control. This usually occurs if your body is resistant to the effects of insulin (called insulin resistance). This is like driving with the hand-break partly on. You need more revs to get going anywhere, and eventually it will damage the car.
Most people with type 2 diabetes make quite a lot of insulin, at least initially. This is more than enough to keep glucose under control in normal circumstances, but not enough to control their glucose levels in the face of this stiff resistance.
How does insulin resistance cause high glucose levels?
Insulin is supposed to suppress your own glucose production and fat release. When insulin levels are low in a healthy body it means there is no food around, so we had better mobilise our stores to keep everybody happy.
However, if the signals that insulin provides are not getting through because of insulin resistance, we keep pouring out sugar and fat when we should be sucking it up. And of course this makes the pancreas work even harder to put it back when it should be resting between meals.
What causes insulin resistance?
In type 2 diabetes the accumulating fat around your waistline releases a range of chemicals that hold back the functions of insulin.
Insulin resistance also happens in every pregnancy, as hormones and other factors released also temporarily causes resistance to the actions of insulin. This means that insulin production needs to be almost doubled to keep glucose levels under control.
Some women do not have the capacity for this increase, especially older women and overweight women who already have reduced their capacity to compensate. Consequently glucose levels rise and gestational diabetes occurs. Although glucose levels usually return to normal after giving birth, women with gestational diabetes have a four-fold increased risk of developing type 2 diabetes as they get older.
How can I reduce my insulin resistance?
The best way to improve your body’s sensitivity to insulin is to lose the fat around your waistline and keep it off, through a good diet and regular physical activity. And even if you don’t lose too much, the more you are able to do more often will make insulin’s job easier, and help reduce your risk of diabetes.
- Carey DG, Jenkins AB, Campbell LV, Freund J, Chisholm DJ. (1996) Abdominal fat and insulin resistance in normal and overweight women: Direct measurements reveal a strong relationship in subjects at both low and high risk of NIDDM. Diabetes. May;45(5):633-8.