Eating more than two tomatoes or more than three portions of fresh fruits, especially apples, daily may help restore the damage.The findings showed that people who quit smoking and ate a diet high in tomatoes and fruits had slower lung decline over a 10-year period. 

This suggests that certain components in these foods might help repair as well as restore the damage caused to lungs as a result of smoking.Poor lung function has been linked with mortality risks from all diseases, including chronic obstructive pulmonary disease (COPD), heart disease, and lung cancer."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," said lead author Vanessa Garcia-Larsen, Assistant Professor at the Johns Hopkins Bloomberg School of Public Health. 

Moreover, the regular intake of tomatoes may also help slow the natural decline in lung function among all adults, including those who had never or had stopped smoking."Lung function starts to decline at around age 30 at variable speed depending on the general and specific health of individuals," Garcia-Larsen explained, in the paper appearing in the European Respiratory Journal."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. Diet could become one way of combating rising diagnosis of COPD around the world," Garcia-Larsen said.For the study, the team assessed diet and lung function of more than 650 adults from Germany, Norway and the UK, and then repeated lung function tests on the same group of participants 10 years later.