An Apple a Day May Keep COPD Away
Chronic obstructive pulmonary disease (COPD) has no cure. Patients with this progressive lung disease can require a host of treatments including medications, mucus-clearing devices, oxygen therapy, vaccinations, and sometimes surgical procedures in order to maintain independence, alleviate discomfort, and extend lifespan.
Lifestyle measures can also help a person maintain a healthy weight and keep activities-of-daily life intact. Any dietary choices that support lung health would obviously be beneficial to someone with COPD or with a high risk of developing COPD. A new study suggests that choosing certain foods may help to repair, limit, or delay lung damage.
Research published in the European Respiratory Journal looked at the relationship between lung health and function, and consumption of dietary antioxidants over a 10-year period.
The 680 adults from three participating countries were part of a bigger research program, the European Community Respiratory Health Survey (ECRHS). This three-phased, longitudinal, multi-center European cohort study examined the role of environmental risk factors on the respiratory health of participants.
In this leg of the study, subjects had a baseline spirometry (FEV1) and forced vital capacity (FVC) measurements taken at the start of the evaluation period. They also filled out a detailed questionnaire.
Food intake was estimated at baseline using food frequency questionnaires (FFQ) which look at foods, consumption frequency, and portion sizes. The lung tests and questionnaires were then repeated at the 10-year mark. At the start of the study, subjects were also categorized into three subgroups: smokers, ex-smokers, and never smokers.
FEV1 measures the amount of air you can forcefully blow out of your lungs in one second. The lower your FEV1, the more severe your COPD is. FVC is the amount of air that can be forcibly expelled from the lungs after taking the deepest breath possible. FVC allows a doctor to monitor lung diseases like COPD to see if the condition is getting worse.
The researchers found that adults who regularly consumed apples and bananas had slower rates of decline in their FEV1 and FVC. Tomato intake was associated with slower decline in FVC. Subgroup analysis showed that consumption of the three fruits was associated with slower decline in the FVC of ex-smokers. Consuming herbal tea and vitamin C was also noted to help limit and slow FVC decline.
Of particular note is that these benefits were suggested to have greater impact in those who quit smoking, regardless of the number of pack years. Aging and smoking are two established risk factors for steeper lung function decline in adults. There has been little research to date on the role of diet and its effect on lung disease.
So what do these foods, herbal tea, and vitamin C have in common? They are all sources of antioxidants. Tomato is a rich source of lycopene, an antioxidant. Vitamin C is an antioxidant. Many herbal teas are rich in antioxidants.
Another study in asthmatic adults showed that a 10-day consumption of tomato extract and tomato juice led to reduced airway inflammation, so lycopene in particular may have a role in the diet of individuals at risk of developing COPD (like ex-smokers). There have been other past studies showing a link between better lung health and less decline in FEV1 and consumption of apples, but not vitamins C or E.
Probably one of the strengths of this new study lies in the fact that it was a random community-based study that involved participants from three countries, which means researchers are more comfortable generalizing their results to wider populations. The researchers feel comfortable concluding that dietary factors may play an important role in preserving ventilation function in adults. Antioxidants from fresh food sources may also uniquely help to not only slow decline, but also to possibly offer restoration of function following lung damage caused by smoking in ex-smokers.
Issues with the study included that researchers did not accumulate information on nutrient supplementation, and they did “assume” that the adult diets mostly remained stable during the 10 years of the study.
How should you use this information? Current dietary guidelines recommend that most adults consume 10 total servings of fruits and vegetables every day. Benefits from these whole foods are numerous. Based on this study, ex-smokers and individuals at risk of developing COPD should consider including apples, bananas, and especially tomatoes daily as lung-support friends.
Other foods high in lycopene include: watermelon, grapefruit, garden asparagus, papaya, red cabbage, persimmons, and rose hips. It’s important to eat these as whole foods with little adulteration or processing.