'Now Marazziti has looked at the hormonal changes that occur in people who are in love. Her team measured the blood levels of several key hormones in 12 men and 12 women who said they had fallen in love within the past six months. The researchers compared these hormone levels to those in 24 other volunteers who were either single or in stable long-term relationships.
'The first finding was that both men and women in love have considerably higher levels of the stress hormone cortisol, indicating that courtship can be somewhat stressful. "But the most intriguing finding is related to testosterone," says Marazziti.' (New Scientist article).
