The idea of the Quantified Self (QS) is that you can’t really understand anything without measuring it. This ‘big data’ trend has been applied in all sorts of fields – for example, former New York mayor Michael Bloomberg said ‘In god we trust – for everything else, bring some data’.

The big idea behind the QS movement is that we should apply those data techniques to our own personal lives, accurately measuring everything from food intake to how many steps we walk so you can accurately set targets and see where you may be going wrong.

Plenty of the people KG met wanted to use devices like Fitbit and Jawbone to help them lose a few pounds, but people at the extremes of the movement wear as many as 40 devices at once, measuring everything from how much they are sweating to the chemical composition of their tears. Hmm, perhaps you can have too much of a good thing.

If you’re interested in finding out more about the Quantified Self: