We have all heard that love hurts, but research shows romantic love can be a potent natural painkiller.

A Stanford University study led by Sean Mackey discovered love stimulated the dopamine-oriented centers of the brain linked to reward and craving, reported the Sunday Herald Sun.

This is the reason why falling in love can trigger a sense of euphoria and an emotional high.

In the study, the brains of 15 student volunteers, who Mackey described as being wildly in love, were observed via a functional magnetic resonance imaging, a brain scan, as they were exposed to mild pain via a heated device in their hand.

The subjects were alternately shown images of their loved ones, then an attractive friend and finally asked to perform a mental skills test to distract themselves from the pain.

They had greater resistance to pain when looking at the picture of their partner and researchers speculate that is because the brain releases natural painkillers in the first stage of new love.

Scientists have previously shown that emotions have a significant impact on physical health, with research indicating that negative emotions can impair the immune system, while positive ones can boost it.

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