Imagine that: If you could change one of the genes in an experiment, an aging gene, maybe you could slow down aging and extend lifespan.

It was like stepping on to an escalator; I could do anything. I was just made for science.

Carbohydrates, and especially refined ones like sugar, make you produce lots of extra insulin. I've been keeping my intake really low ever since I discovered this. I've cut out all starch such as potatoes, noodles, rice, bread and pasta.

Ageing is very exciting. But if I didn't work on ageing, I'd want to work on the brain. There are really cool techniques you can use now. And bioinformatics. The methods you can use for comparing large data sets - that's so powerful.

The idea that ageing was subject to control was completely unexpected.

Life's too short to not be around nice people.

I eat some fruit every day, but not too much and almost no processed food. I stay away from sweets, except 80 per cent chocolate.