Socks in bed: fashion crime or secret weapon?

Are you one of those people who go to bed in socks in winter? Then you're on my team, and I should warn you that in some people's eyes we've just sunk very, very low.

Few questions divide couples quite so reliably. On one side, Team Socks, who simply can't fall asleep with icy feet. On the other, the purists, for whom socks in bed are about as sexy as a fleece at a candlelit dinner. The good news for those of us in socks: science is on our side.

Warm feet, faster sleep

To fall asleep, our core body temperature needs to drop slightly. And how does the body get rid of heat? Through the hands and feet, among other things. When your feet are warm, the blood vessels widen, the heat can escape, and the body gets the signal that it's time for sleep.

Researchers in Basel showed back in 1999 that people with warm hands and feet fall asleep faster. Fittingly, in Switzerland, where everyone knows by November at the latest exactly what cold toes feel like.

When your feet are ice-cold, on the other hand, the vessels tighten, the heat stays in, and you lie awake counting sheep in puffer jackets.

How to turn a sock into a secret weapon

1. Material matters. Wool, cashmere or cotton let the skin breathe. Synthetics quickly mean sweaty feet, and then the romance is well and truly over.

2. Loose, not tight. A cuff that leaves marks squeezes exactly the blood vessels we're talking about.

3. A fresh pair for bed. Not the socks you've worn all day, please, just don't.

4. Plan B for purists. If you refuse to wear socks, warm your feet before bed with a foot bath or a hot-water bottle. Whether it works quite as well isn't proven, but warm feet are warm feet, and no style crime required.

The verdict

Socks in bed are applied physiology with a cable knit. If your feet are cold, you'll usually fall asleep faster in socks, and the research points that way.

And if that bothers anyone, they're welcome to stretch their own icy feet under the duvet. You know whose calves we mean.