An ingredient found in cocoa beans was nearly a third more effective than cough medicine in stopping persistent coughs, researchers at Imperial College London found. The ingredient, theobromine, contributes to the bitter taste of cocoa. It works by suppressing vagus nerve activity, which is responsible for coughing.

It has been scorned by health experts and slimmers alike. But the humble chocolate bar was yesterday hailed as holding the key to curing the common cough.
An estimated (pounds) 100m is spent on cough medicines in Britain each year, with often dubious results.

Codeine, considered the most effective remedy, is plagued by side effects, including drowsiness, which limit its effectiveness.

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