Making sense of nutrition

A human body is a complicated thing, so it can be really difficult to know what happens when you stuff things - food - into it. We eat so many different things that each interact, and we don't even remember exactly what we ate in a day...let alone honestly tell a researcher. New Scientist recently ran a story, highlighting the nutrition muddle caused by endless conflicting advice. What are we to make of this?  Dr Nenad Naumovski and Nathan D'Cunha from the University of Canberra join Tom to untangle some of this.