What causes hypersensitivity to humidity?

From the Guidelines

Hypersensitivity to humidity is often caused by the body's inability to regulate temperature and moisture levels in humid environments, leading to various physical responses such as breathing difficulties, joint pain, skin irritation, and headaches, as supported by recent studies 1. When humidity is high, sweat cannot evaporate efficiently from the skin, making it harder for the body to cool down. This can trigger various physical responses, especially in individuals with pre-existing conditions like asthma, COPD, or arthritis. Some people may have genetic predispositions to humidity sensitivity, while others may develop it due to underlying health conditions.

Factors Influencing Humidity Sensitivity

• High humidity levels can lead to elevated spore concentrations, which can exacerbate allergic symptoms in sensitive individuals 1.
• Certain fungi, such as Fusarium, Phoma, and basidiospores, require moist conditions for spore release, leading to increased levels during rainy weather or high humidity 1.
• Indoor humidity levels can also contribute to dust mite growth, which can trigger allergic reactions in some individuals 1.

Managing Humidity Sensitivity

• Maintaining indoor humidity levels between 40-60% is recommended for optimal health and comfort, as suggested by recent guidelines 1.
• Using dehumidifiers, air conditioning, and moisture-wicking clothing can help regulate indoor humidity levels and alleviate symptoms.
• Staying hydrated and avoiding triggers like mold, fungi, and dust mites can also help manage humidity sensitivity.
• In severe cases, consulting a healthcare provider may be necessary to rule out underlying conditions that require specific treatment.

From the Research

Causes of Hypersensitivity to Humidity

• Hypersensitivity to humidity can be caused by various factors, including mold sensitization and excessive humidity, as seen in patients with allergic asthma or allergic rhinitis 2.
• The skin's water content and barrier function can be affected by ambient humidity, leading to dryness symptoms and irritation, particularly in low humidity environments 3.
• Excessive humidity can cause airway dysfunction, starting at the cellular and secretion level, and progressing to whole airway function, as seen in the effects of humidified gas on the airway mucosa 4.
• Humidity regulation can play a role in the management of asthma patients sensitized to house dust mites, as house dust mites are sensitive to humidity and their populations can be reduced by controlling humidity levels in the home environment 5.

Factors Contributing to Hypersensitivity

• Mold sensitization is highly associated with more severe asthma, and humidity is more of an exacerbating factor in patients with allergic asthma as compared with allergic rhinitis alone 2.
• Low humidity can cause dryness symptoms, such as dry skin, dry eyes, and dry nose, particularly in indoor environments with low humidity levels 3, 6.
• High humidity can lead to airway hyperresponsiveness and exacerbate symptoms in patients with allergic asthma 2.
• The use of humidifiers can deliver excessive water to the airway, potentially causing pulmonary injury, and should be used with caution to avoid raising the average tracheal mucosal temperature above 43°C to 45°C 4.