The Ancient Incas knew it, as does Bridget Jones and that kindly person who always gives you their last Rolo. Ever since humankind grew its first sweet tooth, there’s been nothing like chocolate to raise the spirits.

For years, academics have tried to discover exactly what makes it so irresistible – speculating that key ingredients like cocoa beans, caffeine or any of its other 300 compounds can boost energy and libido.

But now scientists at Cambridge University have carried out brain scans that suggest a much more simple explanation. Chocolate is linked to feelings of wellbeing because it simply tastes so good.

They claim munching a bar induces sensations that could be even more pleasurable than listening to your favourite music, winning the lottery, or falling in love.

Cambridge neuro scientist Adrian Owen said the balance of the evidence suggested that

it was more to do with the taste than any psychoactive chemicals.

The average bar of chocolate, he claimed, simply did not contain enough mood-altering substances to make a difference – some of them, for example, were found in higher doses in a lump of Cheddar cheese or sausage.

Dr Owen, who works at the university’s Wolfson Brain Imaging Center, said: “The scientific data suggests that the mood-enhancing effects of chocolate are not pharmacological – the constituents of chocolate do not appear to affect the brain via a direct biological action.

“An alternative explanation is that the effects of eating chocolate are psychological – the unique combination of aroma, texture and taste makes eating chocolate a pleasurable experience that stimulates the emotional ‘feel-good’ centres of the brain. In short, the chocolate tastes good, so we feel good.

The evidence for this are scans that have tracked changes in the activity of the orbifrontal-cortex – on the brain’s surface – which analyses the “rewardî value of incoming inform action to the brain.

As scans on a group of volunteers show ed (see above), the orbifrontal cortex glows even more when they were munching a bar of chocolate than when they were listening to pleasant music.