article_snippet.sent: Sales of protein powder - which can be priced up to  
article_snippet.sent: £45 per kilogram tub - are rocketing in the UK, growing from £73m in 2007 to £170m in 2012.
article_snippet.sent: They are expected to reach £358m by 2017, according to the market-analyst Euromonitor, as gym-going Brits add the stuff to post-workout smoothies and drinks in a bid to build muscle.