‘Two for one’, ‘buy one get one free’, ‘all you can eat buffet’. These phrases are part of our everyday lives and they’re all designed to make us buy more. We all love a bargain but when it means we’re eating twice as much food as we should, our health suffers, with obesity the major problem.  We’re literally killing ourselves with overeating. So what’s happening and how are we getting it so wrong when it comes to our portion sizes.