Flavonoids are a diverse group of plant compounds found in fruits, vegetables, and certain beverages like tea. They are known for their antioxidant, anti-inflammatory, and immune-modulating properties. Scientific evidence supports the role of flavonoids in supporting lung health, primarily through their ability to reduce oxidative stress and inflammation, which are important factors in the pathogenesis of respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD), and lung infections.

Several epidemiological studies have found associations between higher dietary intake of flavonoids and improved lung function or lower risk of respiratory disease. For example, a 2017 review in Nutrients discussed the positive effects of flavonoids on lung health, noting that certain subclasses like flavan-3-ols and anthocyanins are linked to reduced decline in lung function among adults. In addition, experimental studies have shown that flavonoids such as quercetin, hesperidin, and catechins can modulate inflammatory pathways and protect lung tissues from damage in animal models and cell cultures. However, clinical trials in humans are limited, and more research is needed to confirm the extent of these benefits and the best sources, doses, and combinations of flavonoids.

Overall, while there is promising scientific evidence for the use of flavonoid mixtures in supporting lung health, the evidence is not yet definitive, and most data comes from observational or preclinical studies.