A common misconception is that type 1 diabetes is caused by unhealthy eating and lack of exercise. Doctors actually believe that T1D is caused by an environmental trigger in people with a genetic marker, not because of unhealthy lifestyle choices.
An individual will inherit a predisposition (or genetic marker) and an environmental trigger will cause the disease to “surface”. Some studies have shown these environmental triggers can be caused from climate or colder weather, viruses or event stress levels.
While these studies are in the beginnings stages, it's important to know that both factors are unpreventable. There is no way of knowing when these two elements will work together to produce type 1 diabetes.