How do air conditioning and heating affect eye health?

Did you know that spending many hours in air-conditioned or heated spaces can worsen eye discomfort? Prolonged use of air conditioning or heating can alter the balance of the tear film and contribute to the development of dry eye syndrome, one of the most common reasons for an ophthalmology consultation.

How does air conditioning affect your eyes?

Although air conditioning provides thermal comfort, it can have a harmful effect on the eyes for several reasons:

• It reduces ambient humidity, which encourages tear evaporation.
• It generates direct currents of cold air that dry out the ocular surface even further.
• It is often used in enclosed offices, where natural ventilation is limited.

In these environments, many people begin to notice persistent symptoms without directly associating them with air conditioning. At Barraquer, we frequently see patients with eye discomfort that improves when they reduce their exposure to air conditioning.

Effects of heating on the ocular surface in winter

In winter, heating systems operate continuously, creating a warm but extremely dry environment. This environmental dryness causes:

• Accelerated tear evaporation
• Inflammation of the ocular surface
• Worsening of symptoms in people already diagnosed with dry eye

In addition, the temperature difference between the cold outdoors and warm indoor spaces can cause ocular thermal stress, affecting the stability of the tear film.

Combined risk factors

The risk of developing dry eye due to air conditioning or heating increases when other factors are also present:

• Use of contact lenses: reduces corneal oxygenation
• Advanced age: natural reduction in tear secretion
• Menopause: hormonal changes that affect the tear film
• Smoking: increases ocular inflammation
• Screens: reduce blinking frequency

How to prevent dry eye in air-conditioned or heated environments

At Barraquer, we recommend some simple but effective strategies to protect eye health:

• Avoid direct airflow onto the eyes.
• Use humidifiers in offices or bedrooms.
• Blink frequently, especially when using a computer.
• Apply preservative-free artificial tears in air-conditioned or heated environments.
• Take visual breaks with 5-minute pauses — getting up, looking into the distance, applying tears, drinking water, etc. — every hour of screen use.

When to see an ophthalmologist

Although some symptoms may be relieved with basic measures, if discomfort persists or worsens, it is essential to seek a specialist assessment. At Barraquer, we perform a complete dry eye diagnosis, evaluating:

• Tear quality and quantity
• Tear film stability
• Condition of the Meibomian glands

Depending on the type of dry eye, treatments such as specific eye drops, thermal pulsation or regenerative therapies may be indicated.

Dr Víctor Charoenrook, ophthalmologist at Centro de Oftalmología Barraquer