Flavonoid-rich foods may improve lung health, lower COPD risk

Moderate-to-high intakes of flavonoid result in a reduced risk of chronic obstructive pulmonary disease (COPD) and better lung function, specifically among people with a smoking history, a study has shown.

A total of 119,466 individuals (median age 60 years) from the UK Biobank were included. The researchers estimated intakes of flavonoids, flavonoid-rich foods, and a flavodiet score from 24-h diet assessments among participants

Multivariable-adjusted Cox proportional hazards and linear regression models were used to explore the prospective associations with both incident COPD and asthma and the cross-sectional associations with measures of lung function (%predicted forced expiratory volume in 1 s [FEV1] and FEV1/forced vital capacity [FVC]).

Moderate intakes of total flavonoids, flavonols, theaflavins plus thearubigins, and flavonoids and moderate-to-high intakes of flavonol monomers, proanthocyanidins, anthocyanins, flavones, and the flavodiet score correlated with a reduced risk of incident COPD (hazard ratio, 0.83, 95 percent confidence interval, 0.75–0.92), but not incident asthma, compared with low intakes.

Additionally, higher intakes of all flavonoid subclasses, except theaflavins plus thearubigins, and the flavodiet score resulted in better %predicted FEV1 baseline relative to low intakes. These associations were more pronounced among current and former smokers.

Furthermore, flavonoid intakes showed an inverse relationship with the INFLA score, potentially mediating 11 percent to 14 percent of the association between intakes of proanthocyanidins and flavones and incident COPD.

“Promoting intakes of healthy flavonoid-rich foods, namely, tea, apples, and berries, may improve respiratory health and lower COPD risk, particularly in individuals with a smoking history,” the researchers said.