It's a common phenomenon; a man complains he's feeling too hot and throws off the duvet while his female partner burrows under it and wishes she had some woolly socks.
While each partner accuses the other of complaining, the difference between male and female temperature control is not simply hearsay.
In fact, there are proven differences between men and women when it comes to the way their circulatory system functions.
Women are better at conserving core body temperature - to keep a developing foetus warm - while men's can drop slightly without them noticing.
Originally written for medical blogging site The Hippocratic Post, here we explain exactly why women are always cold...
Female hormones, smaller body size and lower metabolic rate are all factors that contribute to a loss of heat from women.
Women have a higher surface area to volume ratio than men and shed heat faster.
They have less heat-generating muscle mass and tend to get colder around menstruation.
Most importantly, women are better at conserving their core internal body temperature than men, most probably for reproductive reasons, to keep any developing foetus warm.
As a result, when the ambient temperature drops, a woman's circulatory system will divert blood away from her skin and extremities.
A man's core temperature will simply fall slightly and he will be unaware of any change.
Although physiologically there is no structural difference in the circulation between the genders, women can often feel at the mercy of a process we can't control.
We faint more often, we endure hot flushes before and during the menopause and we are more likely to suffer from low blood pressure-induced fatigue and depression.
Cold extremities moreover, can cause more than minor discomfort.
Women are nine times more likely than men to suffer from Raynaud's disease, a painful and often debilitating circulation disorder that affects an estimated 10 million people in Britain.
HUMAN CIRCULATION: A MASTER OF ENGINEERING
When it works efficiently, the human circulatory system is a masterpiece of engineering.
Blood, the body's transport system, is pumped to and from the heart, via an elegantly simple, yet intricate network of blood vessels.
The free-flowing movement of blood round our bodies is central to our health.
Crucially, cholesterol, the modern killer responsible for an epidemic of cardiovascular disease, takes its toll by clogging up our arteries.
By obstructing the passage of blood, this places strain on the heart, which has to pump harder to power circulation.