Researchers from the Mind Lab decided to compare the effects of chocolate and kissing on human body and brains. The volunteers, who were all in their 20s, and had electrodes attached to their scalps as well as heart monitors.

The researchers were comparing their resting heart rates with the heart rates during the chocolate eating and kissing tests.
When it comes to chocolate, it had to melt on their tongues and the kisses were not quick pecks at all.

The testing showed that chocolate melting in mouth caused a more intense and longer lasting body and brain "buzz" comparing to kissing and that it doubled volunteers' heart rates.

The lead author said that although it has been previously known that chocolate had a psychoactive effect, what they found during their measuring is that letting chocolate melt on your tongue could be the secret to maximising the effect.

Kissing did set the heart pounding but the effects did not last as long as with the chocolate that increased heart rates from a resting rate of about 60 beats per minute to 140. The effects were the same in both sexes.

Scientists believe that these strong effects come from the chocolates’ highly stimulating substances phenylethylamine that raises the levels of endorphins, the pleasure-giving substances, in the brain and caffeine that has a stimulatory effect on the brain.

The Mind Lab is funded by members of the food industry, although no firm could be linked to any individual study.