The strikingly slower decline in lung function among former smokers who ate a diet high in tomatoes and fruit, especially apples, suggests that nutrients in their diets are helping to fix damage done by smoking, Garcia-Larsen says. But now including more of tomatoes and fruits in the diet will help to attenuate the decline as people age.
Adults who on average ate more than two tomatoes or more and three portions of fresh fruit a day had a slower decline in lung function compared to those who ate less than one tomato or less than one portion of fruit a day, respectively, the researchers found.
Ex-smokers, who had a diet high in tomatoes, had around 80 ml slower decline over the 10 years.
Vanessa Garcia-Larsen, assistant professor at Johns Hopkins, said, "This study shows that diet might help fix lung damage in people who have stopped smoking".
The researchers also observed a slower lung decline in adults who had the highest consumption of tomatoes, both in former smokers and those who've never smoked.
As per the researchers, in addition to keeping your lungs young, tomatoes have been linked to a decreased risk of prostate cancer and heart diseases. It added that this kind of diet heals damages caused by smoking.
"In public health we're always very focused on treating a disease, but by advising people what to eat we have a unique opportunity to reduce the risk of disease incidence", said Garcia-Larsen. In the study, scientists analysed data from 680 people in Germany, England and Norway who signed up for a health survey in 2002.
Additionally they were given a spirometry test that measures how much oxygen their lungs can take in.
One weakness of the study was that participants' diets were assessed only at the start of the study. The team also included other factors such as participants' weight, age gender, height, level of physical activity and income.
The function of the lungs begins to deteriorate at around the age of 30, and the rate of their demise depends on person's general state of health and other peculiarities.
But she stressed that for people with actual lung illnesses, such as COPD, diet should be seen as a helpful adjunct to medication, not a substitute.