The benefit to the lungs of quitting smoking can be enhanced by controlling weight gain. Smoking is known to lead to a decline in lung functioning. Stopping smoking clearly helps, but often leads to a gain in weight.

A study from University College, London, now tells us what happens if quitting smoking is combined with minimizing weight gain.

A group of 6,600 people in a study on lung health and smoking were sent questionnaires. This showed that weight gain had an adverse effect on lung function, decreasing the benefit of quitting smoking. In general, the benefit was diminished by 38 per cent in men and 17 per cent in women if weight was not controlled. So, although it's true that worry about weight gain should not deter anyone from giving up smoking, plans for healthy eating should accompany plans to quit.

Source

The Lancet 7th May 2005