People who consume a diet high in whole grains and vegetables, and low in processed meat and sugary drinks, lower their risk of developing the serious lung condition, chronic obstructive pulmonary disease (COPD), a new study has found.

COPD is an umbrella term for a number of chronic lung disorders, including bronchitis and emphysema. It is a progressive, disabling condition caused by a narrowing of the airways. The disease currently affects around 380,000 people in Ireland and it is the world's third biggest killer.

While smoking is the main cause, around one-third of those affected are non-smokers, which suggests that there are other factors at play.

French and US scientists decided to look into the potential role of diet, because while a healthy diet is known to reduce the risk of heart disease and cancer, its role in relation to COPD is largely unknown.

They analysed data relating to over 120,000 men and women who took part in two studies between 1984 and 2000. All provided regular details about their diets and those who showed signs of COPD were assessed for the disease.

During the study period, almost 900 of the participants developed COPD.

The scientists found that people who consumed high levels of whole grains, vegetables, polyunsaturated fats and nuts, moderate levels of alcohol, and low levels of red meat, processed meat, refined grains and sugary drinks, had a reduced risk of developing COPD.

In fact, the risk of COPD was a third lower among those who stuck to this diet the most, compared to those who had the least healthy diet.

Furthermore, these findings were similar in both men and women, and in ex-smokers and current smokers.
The scientists found no such link between this type of diet and the incidence of another common lung disease - asthma.

"This is a novel finding that supports the importance of diet in the pathogenesis of COPD. Although efforts to prevent COPD should continue to focus on smoking cessation, these prospective findings support the importance of a healthy diet in programmes to prevent COPD," they commented.

Details of these findings are published in the British Medical Journal.