I'm sure this question is asked a lot. I asked it of two different doctors myself recently, one of them a diabetes specialist. They both said that causing too much sugar did increase the risk. Neither offered any actual evidence. The specialist gave a rather strange reason, which now escapes me.
This idea has inherent plausibility, because eating a lot of sugar could be assumed to stress the body mechanisms that keep sugar level in the blood under control. Too much stress could cause these mechanisms to break down. This is, however, not the reason the specialist gave.
A confounding factor could be that eating too much sugar might cause weight gain, which might increase the risk of diabetes for different reasons.
There are (at least) two kinds of answers that would be useful here.
- Actual clinical trials/studies attempting to address this question.
- Descriptions of medical research which suggest mechanisms by which excessive sugar consumption could increase the likelihood of diabetes.
The term "too much", of course, is ill-defined. An answer could attempt to quantify this.