Health gem

If you do one thing this week... order the smaller pizza

If you do one thing this week . . . order the smaller pizza

The dark, cold nights of winter are rolling in, and sometimes the temptation to hibernate and order a takeaway can be strong.

If you dial out for dinner, though, bear in mind that it can be easy to underestimate how much portion size makes a difference to the amount of carbohydrates, fat and calories that land in your tummy if you eat the lot.

Take pizza, for example: the nine-inch version doesn’t sound that much bigger than the seven-inch. But do the maths: the area of a circle (your dinner) is “pi times r-squared” – so the radius (r) is key.

When you jump from seven to nine inches you add an inch of radius, and that amounts to a whopping 65 per cent increase in surface area, or the amount that covers your plate.

So if you are watching what you eat, avoid portion distortion and order the small.

Claire O'Connell

Claire O'Connell

Claire O'Connell is a contributor to The Irish Times who writes about health, science and innovation