Protein shakes and bars seem part of gym-life but are you wasting money using them to try to bulk up? Newsbeat explores the multi-billion pound protein supplement industry with the help of experts and users, including one who agrees to stop using them for six weeks to see if he can get results by eating protein-rich food instead.
We also meet: a man who damaged his kidneys by taking too many protein supplements; the gym manager who says selling supplements makes up around 60% of their business and one of the country's largest distributors who says the protein supplement industry needs tighter regulation.
