Pizza, like any other junk food, has lots of fat. This will add to your natural reserves and will eventually lead to an oilier skin. This could put some strain on your skin pores and increase the chances of contracting acne.
However, a slice of pizza now and then shouldn’t do you any bad. This is so since no ingredient actively leads to pimple breakouts.
The problem is that eating too much pizza deprives you of the chance to enjoy a balanced diet lowering your immunity and boosting your chances of getting acne.