Sleep. One of the most underrated aspects of health.
Peace of Mind: Stress causes a lot of health issues. Shit's a silent killer.
Less or no sugar altogether: try getting used to not eating sugar at a young age. Loads of health issues can be avoided, and you'd start enjoying natural flavors too.
Oils: the lesser, the better. Use variety of oils instead of relying on only one kind just because someone said it's healthy.
We can't be 100% perfect. We all have one or two bad habits. So regulating the bad stuff—whether it is drinking, smoking, eating junk, etc—regardless of what it is and doing it moderately wouldn't impact your health much.