Do companies advertise ineffective supplements?

DEAR DR. ROACH:

I see supplements advertised on television that are supposed to clear “brain fog” and do many other beneficial things. Are these any good, and can they actually do the things that they claim? If they are effective, why aren’t they sold at drugstores? If not, how is it that companies are allowed to make these false claims and advertise these supplements on television? -- J.L.P.

ANSWER…