Measurements of the temperature of 219 people aged from one to 84 revealed that on average the women were 0.4 degrees Fahrenheit hotter.
Oddly, however, the women had colder hands, which were on average 2.8 degrees cooler than the men's, giving some scientific credence to the saying "cold hands, warm heart."
The finding may explain the commonest bedroom dispute between the sexes - what thickness of duvet0 to sleep under. The greater difference between the core and skin temperatures in women accounts for their greater propensity to feel the cold. Their cool-blooded male partners are meanwhile forced to swelter under layers they would rather do without.
The researchers from the University of Utah, Salt Lake City, who report their findings in the Lancet, found that women get hotter as their menstrual cycle advances with a higher core temperature in the last 14 days than in the first 14 days. Post-menopausal women over 50 were cooler than premenstrual girls under 13.
Weight only made a difference to the temperature of the men. The fatter they were, the lower their core temperature - suggesting that big men really can keep cool.
t The risk of a heart attack rises in the two weeks after a cold, suggesting the infection may trigger the attack, researchers have found.
A study of 9,500 people, of whom almost 2,000 had a heart attack, found those who had had a cold in the previous 10 days were at almost three times the risk. The risk declined with the passage of time since the cold.
The authors of the study, published in the Lancet, say that inflammation caused by the cold could alter constituents in the blood or tissues which could account for the increase in risk of an attack. Although only 4 per cent of the heart-attack patients in the study had a cold in the preceding two weeks they say their finding could be of great public health interest.
"A better understanding of the role of chronic and acute infections in the aetiology [cause] of acute myocardial infarction [heart attack] may result in new strategies for its prevention and treatment," they say.