Dark-pigmented fruits like red grapes and blueberries, rich in flavonoids may slow the lung function decline that occurs with aging, according to new research presented at the American Thoracic Society 2018 International Conference.
Found naturally in a number of foods, anthocyanins, a type of flavonoids, are the pigments that give red, purple, and blue plants their rich coloring. Previous research has shown that apart from acting as antioxidants and fighting free radicals, anthocyanins may offer anti-inflammatory, anti-viral, and anti-cancer benefits.
Garcia Larsen conducted a study to investigate the association between dietary intake of anthocyanins and lung function decline in middle-aged adults.
In the current study, anthocyanins have been detected in lung tissue shortly after being ingested, and in animals models of chronic obstructive pulmonary disease (COPD). The plant chemicals appear to reduce mucus and inflammatory secretions.
The study analyzed data from 463 adults with median age 44 years from 2002 to 2012. Those included in the current study completed a dietary questionnaire and underwent spirometry at enrollment and upon follow-up. Spirometry is a lung function test which measures the amount of air that a person can forcefully exhale in one second (FEV1), the total amount of air a person can exhale after taking a deep breath (FVC) and the ratio of the two, FEV1/FVC. Participants were then grouped into quartiles based on the number of anthocyanins they consumed.
The study found individuals in the highest, compared to the lowest, quartile of anthocyanin intake had:
- a slower rate of annual decline in FEV1than those in the lowest quartile: -9.8 milliliters per year (mL/yr) vs. -18.9 mL/yr.
- a slower rate of annual decline in FVC than those in the lowest quartile: -9.8 mL/yr vs. -22.2 mL/yr.
- a slower rate of annual decline in FEV1/FVC: -0.02/yr.
The association between anthocyanin consumption and lung function in smokers who had never smoked and those who quit was analyzed by the researchers. The association between high consumption of the flavonoids and reduced lung function decline appeared to be stronger among both never smokers and those who had quit than in the general study population. Among smokers, the study did not find an association between anthocyanin intake and lung function.
The study concluded that dietary intake of sources of anthocyanins is associated with a significantly slower decline in lung function in the general population, specifically in never-and ex-smokers but not among smokers.