Is Quercetin Good for Lungs? Breathing Health Benefits

Is quercetin good for lungs? Research suggests this natural flavonoid may calm inflammation, protect lung tissue, and improve breathing. With more people facing asthma, COPD, and lingering lung issues after COVID-19, interest in natural support is growing. Quercetin, found in many fruits and vegetables, has become one of the most studied plant nutrients for respiratory health.

This guide explains how quercetin works in the lungs, what the studies show, and whether it may play a role in keeping your lungs strong.

What Is Quercetin and Why Might It Help the Lungs?

Quercetin is a plant compound found in foods such as onions, apples, berries, grapes, and tea. It belongs to a group of nutrients called flavonoids, known for their antioxidant and anti-inflammatory effects.

When too many unstable molecules called free radicals build up in the body, they cause oxidative stress. Over time, this stress damages tissues and worsens inflammation. Since both oxidative stress and long-term inflammation play a role in lung disease, quercetin has caught the attention of scientists.

According to research, quercetin may:

• Neutralize free radicals inside lung tissue.

• Calm inflammation in the airways.

• Lower the risk of lung scarring (fibrosis).

• Support repair and growth of airway cells.

• Strengthen overall breathing function.

Because of these combined actions, quercetin is being studied as both a protector and a supporter of lung health.

Is Quercetin Good for Lungs? Evidence from Research

When exploring is quercetin good for lungs, the clearest answers come from scientific studies. While many experiments are in animals or labs, the results are encouraging and show consistent benefits.

Quercetin and COPD

Chronic obstructive pulmonary disease (COPD) is a long-term illness that makes breathing difficult. It is most often caused by smoking, which triggers constant inflammation and tissue damage.

One study showed that quercetin improved lung function and prevented emphysema in mice exposed to cigarette smoke. The supplement reduced swelling, protected lung structure, and helped the animals breathe more easily.

Evidence in humans also looks promising. In patients with COPD, quercetin supported lung cell repair. Because COPD damage is usually thought to be permanent, this discovery suggests a new path toward recovery.

Quercetin and Asthma

Asthma causes inflamed and narrowed airways, leading to wheezing, coughing, and chest tightness. Quercetin may help because it reduces inflammation and relaxes the airways.

In fact, one study found that quercetin reduced airway sensitivity and improved oxygen flow in asthma models. The compound lowered mucus production and eased breathing.

Therefore, quercetin could act as a natural helper for asthma management. However, scientists note that more human studies are needed to confirm these effects.

Quercetin and Post-COVID Lung Problems

After COVID-19, some people struggle with long-term breathing problems, including lung scarring. This condition, often called post-COVID fibrosis or long COVID, can limit quality of life.

Researchers discovered that quercetin reduced lung scarring in post-COVID models. It also supported healing and reduced tissue damage. These results highlight quercetin’s potential role in recovery from viral lung injury.

Even though clinical trials are still limited, the findings point toward quercetin as a promising post-viral support nutrient.

Quercetin and Acute Lung Injury

Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), involve sudden, widespread inflammation. They can develop after infections, blood poisoning (sepsis), or toxic exposures.

According to one review, quercetin helped protect the lungs in ALI. It reduced inflammation and improved oxygen exchange, which are key factors in survival.

As a result, quercetin may be useful in both emergency lung conditions and chronic ones. Still, doctors emphasize the need for more clinical evidence. 

How Quercetin Supports Breathing

Researchers believe quercetin helps the lungs in several ways:

1. Anti-inflammatory power – reduces harmful signals that trigger swelling.

2. Antioxidant defense – fights oxidative stress in fragile lung tissue.

3. Fibrosis prevention – slows collagen buildup, lowering the risk of scarring.

4. Tissue repair – encourages lung cells to heal and grow back.

5. Immune balance – supports healthy immune responses without overreaction.

Together, these effects explain why quercetin has been tested across asthma, COPD, post-COVID issues, and acute injuries.

Quercetin and Lung Cancer Risk

Some studies suggest that diets rich in quercetin may lower lung cancer risk. Because quercetin reduces oxidative stress and inflammation, it could help protect tissues from changes that lead to cancer.

On the other hand, the evidence in humans is still limited. Quercetin should not be considered a treatment for cancer. Instead, it may serve as a protective nutrient when included in a healthy diet.

Can Food Provide Enough Quercetin?

Most people get between 10 and 100 mg of quercetin daily from food. The best sources include:

1. Onions, especially red onions.

2. Apples with their skin.

3. Berries such as blueberries and cranberries.

4. Grapes and cherries.

5. Green and black tea.

6. Leafy greens, including kale and spinach.

Eating a variety of these foods supports natural antioxidant defenses. However, studies on lung health often use higher doses, usually between 250 and 1000 mg per day, which are easier to reach through supplements.

Is Quercetin Safe?

Experts generally consider quercetin in foods safe. Clinical studies show that supplements up to 1000 mg daily are generally well tolerated.

Mild side effects such as headache or stomach upset may occur. Because quercetin can interact with blood thinners and antibiotics, people with chronic conditions should talk to their doctor before starting supplements.

Final Thoughts: Is Quercetin Good for Lungs?

Is quercetin good for lungs? Current evidence suggests yes. Quercetin may protect lung tissue, reduce inflammation, and help the lungs repair themselves. It shows promise for COPD, asthma, emphysema, and even post-COVID recovery.

Still, most of the strongest results come from animal and lab studies. While human evidence is growing, larger trials are needed. For now, quercetin should be seen as a supportive nutrient, not a replacement for medical treatment.

If you are ready to explore its potential, consider Shop Ultra Pure Quercetin™ to support your breathing and overall health.

References

1. Araújo, N. P. D. S., de Matos, N. A., Oliveira, M., de Souza, A. B. F., Castro, T. F., Machado-Júnior, P. A., de Souza, D. M. S., Talvani, A., Cangussú, S. D., de Menezes, R. C. A., & Bezerra, F. S. (2022). Quercetin improves pulmonary function and prevents emphysema caused by exposure to cigarette smoke in male mice. Antioxidants (Basel, Switzerland), 11(2), 181. https://doi.org/10.3390/antiox11020181
2. Huang, M., Liu, X., Ren, Y., Huang, Q., Shi, Y., Yuan, P., & Chen, M. (2024). Quercetin: A flavonoid with potential for treating acute lung injury. Drug Design, Development and Therapy, 18, 5709–5728. https://doi.org/10.2147/DDDT.S499037
3. McCluskey, E. S., Liu, N., Pandey, A., et al. (2024). Quercetin improves epithelial regeneration from airway basal cells of COPD patients. Respiratory Research, 25, 120. https://doi.org/10.1186/s12931-024-02742-0
4. Wang, B., Zhang, Z., Wang, Y., Zhu, R., & Zhang, X. (2025). Exploring the therapeutic effect of quercetin in asthma and pulmonary fibrosis overlap syndrome post-COVID-19. Journal of Clinical Pharmacy and Therapeutics, 2025, 5548573, 14 pages. https://doi.org/10.1155/jcpt/5548573