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MEN who have just fallen in love are often mocked by their friends for being "under the thumb". But they are simply doing what their bodies tell them, scientists say.
Researchers found that men who have recently fallen head-over-heels have lower levels of testosterone than single men or those in long-term relationships.
And the reverse effect is seen in women whose naturally low testosterone levels are given a boost.
As testosterone is linked to aggression, self-confidence and assertiveness, experts say that falling in love can "soften" men and "toughen up" women.
http://www.news.com.au/common/story_page/0,4057,9489720%255E13762,00.html