Suggest Treatment For Hearing Loss

Hi, I am a 30 year old female and lately I have been experincing hearing loss particularily in my left ear. it comes and goes. I hear muffled sounds and it usually happens when I haven't eaten for a long periods of time. like for 12-30 hours. even after I eat my ears pop but the noise is still muffled for a few hours... then my hearing is back to perfect.
Is this serious?
Thank you.