Biologic and Muscle Mass Development

Hello! I have been on Stelara for 9 months. In this time, I have gained about 7 lbs of muscle mass. I have NEVER been able to add muscle mass. My dermatologist suspects that I have pre-clinical IBD and that the Stelara has cleared that up to enable me to absorb the protein that I consume. Both he and my gastroenterologist think that the Stelara may have prevented me from getting formal IBD. Needless to say, I am elated. That said, I cannot find a single reference to muscle mass wasting (or mal-absorption of protein) related to psoriasis. Do any of you have any insights? I feel like this is huge and many who would consider biologics do not take the plunge and have pre-clinical issues like me (especially as they age and aging compounds the protein absorption issues). Thank you for any insights!