One of Britain's biggest health chains is selling illegal cannabis oil, The Mail on Sunday can reveal. High-street favourite Holland & Barrett stocks a brand of oil that contains more than four times the legal limit of tetrahydrocannabinol, or THC, the psychoactive ingredient in cannabis. Manufactured in Holland, Jacob Hooy oil is reportedly the best-selling cannabidiol, or CBD oil, product in Britain. CBD products have surged in popularity and are ...