You can east cheese most likely. In fact many singers can shoot heroin, eat Twinkies and White Castle all day and sing fine. Some people are born without sensitive voices! However, other people aren’t so lucky. The right thing to do is trust your body. If you feel more flemmy after you eat cheese or your producer/vocal coach notices a change in your tone on days when you do and don’t eat cheese, listen to them. Everyone is going to have a different reaction to dairy products depending on their own body. That said (like we said here) it is best practice to avoid it the day you are going to enter the studio or sing in a huge concert in front of a billion people, just to be in optimal shape. Listen to your body, no two people have the same reaction to anything, trust your gut (literally).
At Musformation, we are lucky enough to have a piece of software that tells us what people search in Google before they get to our site. We sometimes see things we feel we should address since perhaps they weren’t clarified correctly the first time and other times, we see questions we never addressed before and would like to shed some light on them.