Why shouldn't Pilots
be concerned about their Health. I had "light circles" and was diagnosed with Ocular Migraines. My Doctor (non-FAA) ordered me off Aspartame, AND cigarettes. Unfortunately for me, I smoked for too long, and ended up with a Heart glitch that cost me my Medical. Live and Learn. I hope your friend survived the Astrocytoma, Aspartame or no, I hope he's OK.