She has a small plastic device that has a slit where you slide the base of the tube through. It ensures you squeeze the paste from the bottom and work your way up, leaving nothing to waste.

When we're down to the last blob of paste, she will insist that there is just that bit more to be used.

So she'll cut the tube into two and scrape what little is left inside the two halves. There's usually enough toothpaste for another two or three brushings.

It's a habit that drives me up the wall.

Mum, I'd say each time I see a scissored-off tube in the bathroom, it's just toothpaste. It's all of, what, $3?

What's there to save? Besides, isn't it unhygienic to leave the paste exposed like that? And surely life is too short to be wrestling with a tube of toothpaste?

It's not the only frugal habit she has.

Read the full story in tomorrow's edition of The Sunday Times.