Can aspartame cause brain cancer?

No. Are you getting your medical information from friends or the internet? If so, stop listening to or reading those sources of misinformation and blatant lies? Do you really think that something like aspartame would still be on the market if that were true. You're too old to fall for that stuff!
Aspartame. It is a controversial subject but fda has cleared aspartame after looking at the evidence. Some people still strongly believe that there is a causal association between aspartame and giomas.