Research suggests older women believe they sleep worse than men - but the reverse is actually true.
A team found older women consistently estimate their sleep to be of shorter and poorer quality than their male peers - but in fact they sleep better.
The Dutch researchers suggest women may require more sleep than men - meaning the same amount of sleep may be satisfactory for men, but not women.
The Erasmus Medical Center study appears in the journal Sleep.
The study involved 956 participants aged 59-79, of which slightly more than half were women.
Women reported an average of 13.2 minutes less total sleep time, and estimated that it took them 10.1 minutes longer to get to sleep in the first place. They also rated their quality of sleep 4.2% lower than men.
However, when sleep was measured objectively, women actually slept for 16 minutes longer than men.
Women's sleep was also of a higher quality, and less fragmented.
Overall, however, women were still more accurate at assessing their own sleep than men.
The researcher said some of the difference was down to the use of sleep medication and the consumption of alcohol.
But lead researcher Dr Henning Tiemeier said he was surprised that women slept longer and better than men.
He said: "The difference between subjective and objective sleep quality arises not because women are more likely to be complainers, but because men strongly overestimate their sleep duration."
The volunteers used an actigraph that can be worn like a watch for an average of six consecutive nights to measure their sleep.
On average men estimated that they slept for a total of 7.01 hours a night, when in reality the average figure was 6.40 hours.
In contrast, women estimated they slept for a total of 6.79 hours a night on average - closer to the real average figure of 6.65 hours.
Use of sleep medication was more common in women (14.9%) than men (6.1%), and women who used medication were much more likely to believe they only slept for a short time.
Use of alcohol was more common in men. Its use appeared to shorten sleeping times.
Sleep expert Dr Neil Stanley said: "It is a commonly held misconception that women have poorer sleep than men. As shown by this study, whilst women report worse sleep, it is actually the men who are having less and more disturbed sleep.
"There has been a surprising lack of objective studies of the gender differences in sleep and this study is maybe useful in provoking further research and perhaps to get men to start thinking about the importance of getting a good night's sleep."
Dr Stanley said men tended to start losing deep, slow wave sleep much younger than women, which can make sleep lighter and more easily disturbed.
However, he said that as people of both sexes get older there were more factors - such as pain, and the need to go to the toilet - that could disturb sleep.
Dr Adrian Williams, director of the Sleep Disorders Centre, at St Thomas' Hospital, London, said the finding might explain why women tended to report more cases of insomnia.