A few days ago Jonathan had the harrowing experience of looking through some photos of himself from 5 years years ago. 

It would appear that some parts of him have gotten bigger than they were.

And so he's been toying with the idea of going on a diet but should he? 

Giles Yeo is a Geneticist in Cambridge University and author of Gene Eating: The Science of Obesity and the Truth About Diets