The Causes

Diabetes Type 1:

  • The exact cause of type 1 diabetes is unknown.
  • What is known is that your immune system — which normally fights harmful bacteria or viruses — attacks and destroys your insulin-producing cells in the pancreas. This leaves you with little or no insulin.
  • Instead of being transported into your cells, sugar builds up in your bloodstream.
  • Type 1 is thought to be caused by a combination of genetic susceptibility and environmental factors, though exactly what many of those factors are is still unclear.


Prediabetes & Type 2:

  • In prediabetes — which can lead to type 2 diabetes — and in type 2 diabetes, your cells become resistant to the action of insulin, and your pancreas is unable to make enough insulin to overcome this resistance. 
  • Instead of moving into your cells where it’s needed for energy, sugar builds up in your bloodstream.
  • Exactly why this happens is uncertain, although it’s believed that genetic and environmental factors play a role in the development of type 2 diabetes.
  • Being overweight is strongly linked to the development of type 2 diabetes, but not everyone with type 2 is overweight.


Gestational Diabetes:

  • During pregnancy, the placenta produces hormones to sustain your pregnancy. 
  • These hormones make your cells more resistant to insulin.
  • Normally, your pancreas responds by producing enough extra insulin to overcome this resistance.
  • But sometimes your pancreas can’t keep up. 
  • When this happens, too little glucose gets into your cells and too much stays in your blood, resulting in gestational diabetes.