The research, reported in The BMJ, analysed data from more than 100,000 people to investigate the association between the Alternate Healthy Eating Index 2010 (AHEI-2010)—a measure of diet quality—and the risk of developing chronic lung diseases such as chronic obstructive pulmonary disease (COPD).
Led by first author Raphaëlle Varraso from INSERM in France, and in partnership with researchers in the USA, the researchers analysed data from the Nurses’ Health Study and the Health Professionals Follow-up Study, finding that a higher AHEI-2010 diet score - reflecting high intakes of whole grains, polyunsaturated fatty acids, nuts, and long chain omega-3 fats and low intakes of red/processed meats, refined grains, and sugar sweetened drinks - was associated with a lower risk of COPD in both women and men.
“A high AHEI-2010 dietary score was associated with a lower risk of newly diagnosed COPD, a novel finding that supports the importance of diet in the pathogenesis of COPD,” wrote Varraso and colleagues – adding that the COPD findings extend the relevance of the AHEI-2010 dietary score to another major chronic disease after previous work linked the dietary score with lower risks of total prostate cancer, obesity, and hip fracture, in addition to lower all cause mortality, and increased healthy ageing and wellbeing.
“Although efforts to prevent COPD should continue to focus on smoking cessation, these prospective findings support the importance of a healthy diet in multi-interventional programs to prevent COPD,” added the team.
Varraso and his team analysed data for more than 120,000 US men and women taking part in the Nurses' Health Study from 1984 to 2000 and the Health Professionals Follow-up Study from 1986 to 1998.
The AHEI-2010 diet score is based on 11 components, with a higher score reflecting high intakes of vegetables, whole grains, polyunsaturated fats, nuts, and long chain omega-3 fats - moderate intake of alcohol - and low intakes of red and processed meats, refined grains, and sugar sweetened drinks.
Participants completed regular questionnaires on dietary intake, and those who reported a diagnosis of emphysema or chronic bronchitis between 1984 and 2000 were also assessed for COPD. Over the study period, 723 cases of newly diagnosed COPD occurred in women and 167 in men.
After adjusting for 12 factors including age, physical activity, body mass index, smoking and ethnicity, the risk of newly diagnosed COPD was found to be around a third lower in participants who ate the healthiest AHEI-2010 diet compared with those who ate the least healthy diet.
According to the team, this is a similar risk finding to ex-smokers and current smokers in both women and men.
"This is a novel finding that supports the importance of diet in the pathogenesis of COPD," said the team.
Source: The BMJ
Published online ahead of print, doi: 10.1136/bmj.h286
“Alternate Healthy Eating Index 2010 and risk of chronic obstructive pulmonary disease among US women and men: prospective study”
Authors: Raphaëlle Varraso, et al