THIS week has not been kind to my waistline.

The problem is not a lack of willpower, but a lack of assertiveness: I’ve tried to be healthy but people won’t take no for an answer.

“Have a home-made mince pie,” said my sister, when I visited her at the weekend.

She had a glint in her eye that scared me, and her voice got slightly louder as she pushed the plate towards me.

“Have a home-made mince pie!”

She had a smile on her face that didn’t quite reach her eyes.

“I’ve spent ages making them - why don’t you want one?!”

I took one and ate it nervously.

“See - I knew you wanted one really!”

On Sunday I met up with a friend for a coffee.

“Go on...be naughty....have a cake,” she said, eyeing the cake display wistfully.

I’d just had lunch and was too full.

“I’m alright, thanks,” I said. “But you have one if you want.”

She looked longingly at the chocolate cake and sighed dejectedly.

“Nobody ever wants cake... I love cake. And I hate eating cake alone.”

She looked me in the eye: “I’m always eating cake alone.”

She didn’t shed a tear, but may as well have done.

“Fine,” I sighed. “Maybe we could share one?”

She grinned and pointed to the biggest, stickiest, most chocolatey cake.

“Two slices of that please!”

A little sign next to the cake said something like: ‘3,000 calories. Per bite.’

I now spend half my life in the gym.

Everything is measured in ‘minutes this will take to burn off on the cross trainer’.

But one bit of unhealthy living I’m happy to embrace is the ‘chocolate-for-breakfast’ advent calendar.

Cadbury’s are telling me I have to eat a square of chocolate every single day and who am I to argue?

As we’ve already established, I just can’t say no. So why try now?