Of course not! Did you see those hats? Cramming a bunch of Reynold's Wrap on your cranium does not a proper tinfoil hat make!
It must be constructed of several overlapping layers with the crystalling structure of the metal crossing at 45 degree angles in an anti-clockwise direction. The layers of aluminum (or aluminium for you) have to be at least 2 mils... none of this deli sandwich wrap or poptart mylar crap.
And, most importantly, the hat cannot conform to the general shape of your head! The best hats only touch the cranium on the rim of the hat..... any other contact results in grounding of the supermagnetoconductauracharge with the brain's long-fingered virtual synapses, not only rendering the hat useless, but creating a ground state that glows like a radar blip for any nearby aliens. Sometimes they laugh at your ineptitude before they kill you and wear your skin to their next blood orgy.