If you are truly feeling hunger, and you're not "stuffing" your feelings, or trying to comfort with food, then it definitely is something your PCP should know about, then maybe your neuro.
I have the opposite problem...I eat reduced portions and can't lose the weight, even if I work out several times a week. I have to be more consistent with watching and journaling what I put in my mouth tho...but my energy level is up and down so much that I know my thyroid isn't working right. I just hope it isn't my pituitary...