I don't know whether it is important to study science at a young age, though current thinking emphasises the need.

My first vote was for a communist in east London when I was a medical student. But I've voted Tory, Labour and Lib Dem in my time.

Following 25 children for the TV series 'Child of Our Time' has been extraordinary. The BBC's original plan was to commemorate the new millennium. What better way than to film a number of expectant mums from across the U.K.? Coming from widely different backgrounds, all were due to give birth on January 1, 2000.

I used to work for the World Health Organisation in poor countries all over the world - Bangladesh, Korea, the Philippines and India. You learn a whole range of things about how other people are living and try to connect with them to gain an understanding of where they're coming from.

However pragmatic you are, it is very demanding being a new parent.

Childhood is not dead. Children were worse off when we were hunter-gatherers; they were threatened in medieval times and exploited during the Industrial Revolution. Was it any better in the time of Charles Kingsley or Charles Dickens?

I like travelling on my own. It means I'm completely free to think about what's around me.