Mechanism of Bird’s Nest in Treating Yin Deficiency-Type Chronic Allergic Cough

Bird’s nest is considered in Traditional Chinese Medicine (TCM) to have properties that nourish Yin, moisten dryness, and tonify the lungs. Therefore, it may be beneficial for Yin deficiency-type chronic allergic cough. The potential mechanisms from both TCM and modern research perspectives are as follows:

1. Nourishing Yin and Moistening the Lungs to Relieve Yin Deficiency Cough

Yin deficiency-type chronic cough is mainly characterized by dry cough with little phlegm, dry throat, and worsening at night, often due to lung Yin deficiency leading to lung dryness and dysfunction in lung Qi circulation. Bird’s nest is sweet and neutral in nature, with strong lung-nourishing and moistening effects, which can help replenish lung Yin, reduce dry cough, and alleviate irritation-induced coughing.

2. Regulating Immunity and Improving Allergic Reactions

Bird’s nest is rich in sialic acid (N-Acetylneuraminic Acid, NANA), which has been found to:

• Enhance immune regulation, reducing the overreaction of the immune system to allergens and thereby decreasing the frequency of chronic allergic cough episodes.

• Reduce inflammation, lowering immune system hyperactivation and alleviating airway hyperresponsiveness.

3. Promoting Epithelial Repair and Strengthening Respiratory Barrier

Bird’s nest contains epidermal growth factor (EGF) and transforming growth factor-beta (TGF-β), which can:

• Promote respiratory mucosal repair, reducing epithelial damage caused by inflammation or prolonged coughing and stabilizing the airways.

• Enhance airway barrier function, reducing irritation from external allergens, thereby decreasing the susceptibility to allergic cough.

4. Regulating the Gut-Lung Axis to Reduce Chronic Inflammation

In TCM, the lungs and large intestine are considered to be closely related. Modern research also suggests that gut microbiota balance plays a crucial role in immune regulation and chronic inflammation. The bioactive compounds in bird’s nest (such as sialic acid, proteins, and peptides) may:

• Improve gut microbiota, reducing gut inflammation and enhancing immune tolerance, thereby decreasing the occurrence of chronic allergic cough.

• Suppress excessive Th2 immune responses, lowering IgE-mediated allergic reactions and relieving allergic cough symptoms.

5. Reducing Oxidative Stress and Protecting the Lungs

Bird’s nest contains various antioxidant components (such as peptides and sialic acid) that can:

• Reduce oxidative stress, lowering airway inflammation caused by free radical damage.

• Prevent airway remodeling, mitigating long-term structural changes in the airways caused by chronic allergic cough.

Conclusion

Bird’s nest may help alleviate Yin deficiency-type chronic allergic cough through nourishing the lungs, regulating immunity, repairing the mucosa, improving gut microbiota, and reducing oxidative stress. However, its effectiveness varies among individuals. It is recommended to combine bird’s nest with other TCM treatments (such as Sha Shen Mai Dong Tang or Bai He Gu Jin Tang) and consume it under professional guidance for optimal results.