Hopefully soon we can engineer an eat watch http://www.fourmilab.ch/hackdiet/e4/eatwatch.html http://www.fourmilab.ch/hackdiet/e4/eatwatch.html The rest of the

Hopefully soon we can engineer an eat watch http://www.fourmilab.ch/hackdiet/e4/eatwatch.html http://www.fourmilab.ch/hackdiet/e4/eatwatch.html The rest of the Hacker's Diet is worth reading and has an excellent analytical approach to describe the eating (inputs) and energy use / exercise (outputs) of a simple model for your body.