Forget low-carb, high-fat ketogenic diets, gluten-free foods and all things detox. These are diet bygones compared to a slightly-sparkling, gold-coloured fermented drink called kombucha that is now all the rage. They say Madonna drinks it, so does Halle Berry, Lindsay Lohan and Gwyneth Paltrow. Even testosterone-fuelled Jake Gyllenhaal and Orlando Bloom were seen clutching a bottle.
