In general, pregnant women need to eat about 300 extra calories a day.

If you park 15 minutes away from your office, you'll also burn an extra 130 calories per day.

For the first six months your body doesn't need a single extra calorie.

Six days a week for three months, the twins were given 1,000 extra calories.

Your body must work to warm the water up, burning a few extra calories in the process.

You could double up for another £1 but had to work out how many extra calories that would be yourself.

And what should I eat for those extra 500 calories?

We often walk all the way to justify the extra calories.

Those 200 or so extra calories have to go somewhere.

But the interesting question is, Where, exactly, did all those extra calories come from in the first place?