Simon says: The simple answer is yes. According to the British Thoracic Society - which produces the UK's guidelines for treatment of the disease - there is evidence that good control of asthma when you're younger helps prevent longer-term breathing disability. Asthmatics have chronic inflammation in the air passages (bronchi) of their lungs. This inflammation can be controlled by the so-called preventer inhalers which contain various steroid drugs. However, if not controlled, this inflammation can cause permanent damage to the bronchi over time through a process called airways remodelling. This basically leads to scarring and narrowing of the bronchi, and poor response to asthma treatments. Those with severe childhood asthma are more likely to run into this problem, as are those who smoke.