How risky is very light smoking?

Bad to do this: All inhaled smoke to any degree is a bad thing to do to your body. You do not lower the risk of death by cancer significantly by smoking lightly. If you are motivated to lower your cigarette use, (congratulations) then you should be motivated to stop altogether. Go for it.

Risky.: Even smoking one cigarette daily can cause health problems. No amount of cigarette smoking is safe.