Eating more fruit could reduce the impact of air pollution on the lungs, a study has suggested.
This could be down to the antioxidants naturally present in fruit, according to researchers.
The effect was also more pronounced in women who consumed four portions of fruit or more a day.
To explore the links between a healthy diet and better lung function, academics from the University of Leicester looked at UK Biobank data from 207,421 people.
Researchers compared their diets, including intake of fruits, vegetables and wholegrains, with lung function – or FEV1, the amount of air exhaled in one second.
Air pollution was measured as fine particulate matter (PM2.5), the concentration of tiny particles released into the air by the likes of cars and factories.
The team found that for every exposure to PM2.5 of five micrograms per cubic metre of air, FEV1 reduced by 78.1ml in people who did not eat a lot of fruit.
This compared with a 57.5ml reduction in women who consumed a lot of fruit.
Researchers said men generally reported eating less fruit than women, which could explain why the protective effect was seen in females.
Pimpika Kaewsri, a PhD student from the Centre for Environmental Health and Sustainability at the University of Leicester, presented the findings at the European Respiratory Society Congress in Amsterdam.
She said: “Our study confirmed that a healthy diet is linked to better lung function in both men and women regardless of air pollution exposure.
“And that women who consumed four portions of fruit per day or more appeared to have smaller reductions in lung function associated with air pollution, compared to those who consumed less fruit.
“This may be partly explained by the antioxidant and anti-inflammation compounds naturally present in fruit.
“These compounds could help mitigate oxidative stress and inflammation caused by fine particles, potentially offsetting some of the harmful effects of air pollution on lung function.”
Professor Sara De Matteis, chairwoman of the European Respiratory Society’s expert group on occupational and environmental health, said it “confirms the potential respiratory health benefits of a healthy diet, especially rich in fresh fruit intake”.
“However, access to a healthy diet is not equally distributed in the population and, even if the authors adjusted for socio-economic-status, some residual confounding cannot be ruled out,” she added.
“A healthy plant-rich diet should be promoted in the population starting from primary school, not only for preventing chronic diseases, but also to reduce the carbon footprint of meat-rich diets.”
Sarah Sleet, chief executive at Asthma + Lung UK, said: “We know that a high fruit diet supports lung function, but it’s an interesting step forward in this study to see that it could also counteract the effects of air pollution on our lungs.
“Fruit and vegetables, particularly those high in vitamin C and K, can really help support our lungs to function well. While eating more fruit isn’t a replacement for taking your medication as prescribed, enjoying fruit as part of a balanced diet looks like it can help our lungs when they’re faced with external pressures like air pollution.
“However, it is important to remember that there is unequal access to healthy foods, largely driven by cost. In addition, air pollution continues to hit people who are the poorest and from an ethnic minority background the hardest.
“The Government must do more to address the disproportionate exposure to air pollution that contributes to worsening health inequalities, which is why Asthma + Lung UK is calling on the Government to introduce stronger, legally binding air quality targets that align with World Health Organisation guidelines.”
