Why do I feel like I can't breathe when wearing a mask?

In daily life, many people experience a feeling of “not being able to breathe normally” when wearing a mask, especially when they first put it on or after wearing it for a long time. This feeling is not rare; rather, it is a common subjective experience shared by many people. So where does this discomfort come from? Is it caused by real physiological limitations, or is it more related to psychological perception? Below, we explore this phenomenon from multiple perspectives.

Masks do not block oxygen or reduce blood oxygen levels

A large body of scientific research and medical expertise shows that properly made masks—whether surgical masks or cloth masks—do not significantly reduce the amount of oxygen we inhale, nor do they meaningfully lower blood oxygen levels.

Oxygen molecules are extremely small and can easily pass through the filtering layers of masks. Even healthcare workers who wear masks continuously for hours in operating rooms do not suffer from oxygen deprivation due to mask use.

International health authorities have also emphasized that standard masks are designed to allow air to flow in and out freely. Even high-filtration masks such as N95 respirators only slightly increase breathing resistance and do not significantly alter lung function in healthy individuals.

Why does it still feel like breathing is restricted?

1. Slight physical resistance

Although masks do not block oxygen, the material does create some airflow resistance. This means the body must exert slightly more effort to breathe through the mask. This sensation can be more noticeable with higher-protection masks that have denser filtering layers.

This added resistance is not a serious physiological barrier—it is a minor physical change. Because people are not used to this extra effort, the brain may interpret it as “difficulty breathing,” even though actual oxygen intake remains adequate.

2. Changes in breathing pattern

When wearing a mask—especially for the first time or for long periods—people often unconsciously change their breathing patterns:

Some begin breathing more shallowly and rapidly.

Others adjust their breathing due to warmth and moisture buildup inside the mask.

This unconscious change is sometimes referred to as a disruption in normal breathing rhythm, which can lead to sensations of dizziness, tightness, or “not getting enough air.”

In reality, this is not true oxygen deprivation but rather a mismatch between bodily sensations and the brain’s interpretation of them.

3. Temperature and humidity changes

When wearing a mask, exhaled warm air and moisture accumulate inside it, increasing temperature and humidity around the mouth and nose. This can create a stuffy or uncomfortable feeling that mimics breathing difficulty.

These environmental changes stimulate sensory receptors in the skin and respiratory system, creating discomfort. However, this is a perceptual issue rather than a dangerous physiological one.

4. Psychological and anxiety-related factors

Many psychologists point out that a large part of perceived breathing difficulty is psychological. The unfamiliar feeling of wearing a mask, a sense of confinement, or anxiety related to illness can trigger what is sometimes called “breathing anxiety.”

Research shows that merely believing one cannot breathe properly can produce physical symptoms such as chest tightness or heart palpitations—an example of the mind-body connection.

Because masks are often associated with disease or danger, this emotional stress can heighten awareness of breathing and amplify discomfort.

Can masks ever cause real breathing problems?

While most people experience only subjective discomfort, there are situations where caution is warranted.

1. People with severe respiratory conditions

Individuals with serious asthma, chronic obstructive pulmonary disease (COPD), or significant heart or lung disease may genuinely find mask-wearing more challenging. In such cases, medical advice should guide mask use.

2. Intense physical activity

During high-intensity exercise, the body requires much more oxygen. Wearing a mask in these situations can make breathing feel more laborious. Although oxygen levels may remain adequate, the added effort combined with physical exertion can increase the sensation of strain.

How to reduce the feeling of breathlessness while wearing a mask

1. Practice controlled breathing

Slow, deep breathing can help regulate airflow and reduce anxiety. Techniques such as “box breathing” (inhale-hold-exhale-hold in equal intervals) may improve comfort.

2. Allow time to adapt

It is normal to feel uncomfortable at first. Gradually increasing the duration of mask use helps the body and mind adjust over time.

3. Choose the right mask

A well-fitting mask that is snug but not overly tight can reduce discomfort. Masks that press too hard against the face or nose can increase the feeling of restriction.

Proper masks do not significantly reduce oxygen intake or cause dangerous carbon dioxide buildup.

The sensation of breathlessness usually arises from mild airflow resistance, psychological factors, and the body’s adjustment to a new experience.

Only in cases of severe respiratory illness or during extreme physical exertion might masks meaningfully worsen breathing difficulty.

Therefore, most people do not need to worry that wearing a mask will cause oxygen deprivation or serious health risks. Understanding these mechanisms can help reduce anxiety and make mask-wearing more comfortable.