Have you tried expressing to see how much milk he is taking in?? as you said he is a healthy weight and i assume produces lots of nappies?? (a good indictaion he's getting enough from his milk feeds)
, if so then maybe it could be time to introduce a little food if you think it is hunger??
I know on the norm its usually around 5/6 months to begin weaning but some babies are early starters some later.
You could try to give him something once a day (lunchtime is best to start incase has any tummy upset from new food to digest rather than evening time) and see if his appetite lessons for milk. If he takes to wanting some food you know he is ready for it. If you feel comfortable you could then express some milk feeds as you suggested it may be more for comfortthen for hunger that he wants many feeds then you could keep morning and night (bedtime) to breast feed?? just an idea
Just suggestions from things iv herd/tried/suggested to family,friends with young babies hope may help