Sleeping in bed with a woman impairs a man’s mental abilities the next day and increases stress hormones, a study has found. This is despite most men reporting a better night’s sleep alongside a woman, and happens regardless of whether the couple has sex. The impairment doesn’t appear to apply to women.

BBC:

Sharing a bed with someone could temporarily reduce your brain power – at least if you are a man – Austrian scientists suggest.

When men spend the night with a bed mate their sleep is disturbed, whether they make love or not, and this impairs their mental ability the next day.

The lack of sleep also increases a man’s stress hormone levels.

According to the New Scientist study, women who share a bed fare better because they sleep more deeply.

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