饭量／酒量／烟瘾小的人
someone who eats/drinks/smokes only a little
The recipe will feed eight light eaters or six hungry people.
If you are a light eater, I recommend snacking on Vietnamese summer rolls.
I am only a light drinker and my husband doesn't drink alcohol at all.
Even light smokers are more at risk of lung cancer than non-smokers.
I am a light smoker but I do enjoy a cigarette after a meal.
See also: light adjective (NOT MUCH)