To do so, they examined the diet and lung function of more than 650 adults in 2002, following up with the individuals 10 years later. The participants, which were from Germany, Norway, and the United Kingdom, completed a questionnaire, which assessed their eating habits, and they also underwent spirometry, a procedure that measures the capacity of lungs to take in oxygen.
After analyzing the results, they found that the natural decrease of the lung function was slower for former smokers with a diet high in tomatoes and fruits, particularly apples.
Scientists also discovered a slower decline in lung function for all adults who ate lots of tomatoes, even those who had never smoked or had quit smoking.
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In fact, those who consumed more than two tomatoes or more than three portions of fruit a day had a slower decline in lung function, compared to the subjects who ate less than one tomato or one portion of fruit a day.
"This study shows that diet might help repair lung damage in people who have stopped smoking. It also suggests that a diet rich in fruits can slow down the lung's natural aging process even if you have never smoked," coauthor Vanessa Garcia-Larsen said in a statement.
Researchers hope to continue their investigations to confirm their results and believe their findings can be used to help patients at risk for respiratory diseases, including COPD.
"Our study suggests that eating more fruits on a regular basis can help attenuate the decline as people age, and might even help repair damage caused by smoking,” Garcia-Larsen said. “Diet could become one way of combating rising diagnosis of COPD around the world."
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