British scientists believe that Asthma could be cured within five years after they discovered what causes the condition and how to switch it off.

Researchers at Cardiff University and Kings College London identified which cells cause the airways to narrow when triggered by irritants like pollution.

The scientists wrote in the Science Translational Medicine that they are hopeful that in the future asthmatics take the drug to prevent an attack ever happening and ending the need to constantly carry an inhaler.

"Our findings are incredibly exciting," said Professor Daniela Riccardi, from Cardiff University School of Biosciences.

"If we can prove that calcilytics [ which can be used to treat osteoporosis] are safe when administered directly to the lung in people, then in five years we could be in a position to treat patients and potentially stop asthma from happening in the first place."

Asthma is a debilitating condition which can cause coughing, wheezing, chest tightness and breathlessness. Inhalers can manage the problem, but some people do not respond to current treatments.

Dr Samantha Walker, Director of Research and Policy at Asthma UK, who helped to fund the research, told the Daily Telegraph: "This hugely exciting discovery enables us, for the first time, to tackle the underlying causes of asthma symptoms.

"Five per cent of people with asthma don't respond to current treatments so research breakthroughs could be life changing for hundreds of thousands of people.

"If this research proves successful we may be just a few years away from a new treatment for asthma, and we urgently need further investment to take it further through clinical trials.

"Asthma research is chronically underfunded; there have only been a handful of new treatments developed in the last 50 years so the importance of investment in research like this is absolutely essential."