Advertising itself is inherently malware. If I can’t view a site without ads, I don’t visit that site.
Which, in combination with Javascript blocking, is how I get away with not running an anti-virus (to kill my machine resources) and still never get any malware.
I think that used to be true with old versions of Internet security suites, but as a current subscriber of Norton Internet Security, the current version I use is very effective and uses very little system resources.