If you are feeling anxious, try sniffing the armpit of the nearest sweaty male. OK, that might not be possible – or even desirable – but a study conducted at the Monell Chemical Senses Center in Philadelphia, USA, found that women reported feeling more relaxed after six hours of exposure to male underarm secretions. The effect is a response to men’s pheromones, natural body chemicals that act as regulators of mood and influence female hormonal changes. According to researchers, the ability to isolate active pheromones could lead to advancement in fertility and pre-menstrual syndrome treatments, providing yet another good reason to snuggle up closer to the one you love.