The causes of diabetes mellitus are numerous and may change from person to person. They will also be different depending on whether you have type I or type II diabetes. The final type, gestational diabetes, is triggered by a woman becoming pregnant and generally only lasts as long as the gestation period, but can leave her more susceptible to type 2 diabetes in the future.
Causes of Type One Diabetes
At a very general level, interactions between genetic inheritance and infections or viruses cause type I diabetes. The general theory of the causes of diabetes mellitus type I is that a person is born with a genetic disposition towards the disease but it is unlikely that a baby will have diabetes from birth. A virus or an infection generally triggers type I diabetes, which typically strikes during infancy or adolescence.
This disposition to diabetes means that any disease that attacks the immune system will affect the pancreas causing it to shut down. Sadly, no test exists for predisposition to type I diabetes at present, so the first that most sufferers know about it is when they are diagnosed with the illness.