Horizon 2018 Episode 11 Vitamin Pills: Miracle or Myth? ( Air Date 2018-10-25 ) Genre Documentary category. Overview "Nearly half of us take a vitamin or mineral supplement every day, but what are these pills sold on every high street actually doing? Digging deeper than the eye-catching words on the packaging, Dr Giles Yeo investigates who really needs a supplement by putting our diets to the test.".