Sugar is not bad. Use eating refined sugar is bad.

Eat fruit, where sugar comes with fiber and vitamins/minerals and you will be fine (you are biologically a primate and they binge on fruit -- fruit and thereby sugar should thus be fine as our main source of calories).

One note to add: primates do not eat fatty foods and humans do. In the presence of fat, we cannot handle sugar (and thus fruit) very well and may lead to type2.