Being overweight can contribute to breathlessness and shortness of breath, particularly during walking, exercise or other physical activity. Excess weight around the chest and abdomen can restrict movement of the diaphragm and make it harder for the lungs to expand fully, increasing the effort required to breathe.
However, breathlessness should not automatically be assumed to be caused by weight. It can have many different causes, including respiratory and cardiovascular conditions, and persistent or worsening breathlessness should be properly assessed.
Obesity can also affect respiratory health in other ways. It is associated with conditions including obstructive sleep apnoea, obesity hypoventilation syndrome and asthma, which are discussed below.
Why can being overweight cause shortness of breath when walking?
Walking and other physical activities increase the amount of oxygen the body needs, so the heart and lungs have to work harder. Carrying excess weight can increase this workload and may make you feel out of breath more quickly, particularly when walking uphill, climbing stairs or exercising.
Excess weight around the abdomen and chest can also restrict movement of the diaphragm and reduce the amount the lungs can expand during breathing. Reduced fitness may contribute to breathlessness as well.
However, becoming unusually breathless when walking should not automatically be attributed to weight or fitness. If breathlessness is new, worsening, occurs with relatively little activity or is affecting your everyday life, it is important to seek medical advice so that other possible causes can be considered.
Carrying excess weight increases a person’s risk of developing certain respiratory diseases:
Obstructive sleep apnoea
One of the most common of these is obstructive sleep apnoea. This occurs when fat around the neck and throat affects the airways during sleep, leading to intermittent pauses in breathing. When this happens, the quality of sleep is diminished. You may experience daytime fatigue and have a greater chance of developing cardiovascular diseases.
Obesity hypoventilation syndrome
Because excess weight interferes with normal breathing, you may develop high levels of carbon dioxide combined with low oxygen levels in the blood. This is called obesity hypoventilation syndrome and, if left untreated, it can result in severe respiratory failure.
Asthma
Obesity can lead to an increase in asthma symptoms. This is because obesity impacts lung function, causes systemic inflammation and alters the body’s immune responses. Studies demonstrate that not only are people with obesity more likely to develop asthma, but they are also prone to more severe symptoms [1].
COPD
COPD (chronic obstructive pulmonary disease) is primarily associated with smoking, however, obesity can also play a role as it affects respiratory function and is associated with a tendency towards a more sedentary lifestyle. Obesity also contributes to inflammation of the airways.
When should breathlessness be investigated?
Although being overweight can contribute to breathlessness, it is important not to assume that weight is always the cause. Shortness of breath can also be associated with respiratory conditions such as asthma, COPD and sleep apnoea, as well as heart conditions and other health problems.
You should consider seeking medical advice if your breathlessness is new, becoming progressively worse, occurs during normal everyday activities, or is affecting your ability to exercise or carry out daily tasks.
f you are experiencing persistent or unexplained breathlessness, a respiratory assessment can help determine whether excess weight is contributing to your symptoms or whether another underlying condition may need investigation.
Treatments for managing respiratory diseases linked to obesity
Treatment will depend on what is causing the breathing difficulties and whether excess weight is contributing to the symptoms. Where appropriate, gradual and sustainable weight loss may help reduce the effort required to breathe and improve mobility and exercise tolerance.
Lifestyle changes, including regular physical activity and a balanced diet, may form part of the approach, with specialist support from physiotherapists, dietitians or weight-management services where appropriate.
Any underlying respiratory condition will also need to be managed according to the individual diagnosis. For example, asthma may require inhaled medication, while obstructive sleep apnoea may be treated with continuous positive airway pressure (CPAP) in appropriate cases.
For people experiencing persistent or unexplained breathlessness, the first step is establishing the cause rather than assuming that weight alone is responsible.
Frequently Asked Questions
Yes. Carrying excess weight can increase the effort required to breathe and may restrict movement of the diaphragm, particularly during physical activity. However, breathlessness can have many causes and should not automatically be attributed to weight.
Yes. Walking increases the body’s demand for oxygen, and carrying additional weight increases the workload on the heart and lungs. Reduced fitness can also contribute. New or worsening breathlessness should be assessed rather than assumed to be caused by weight alone.
For people whose excess weight is contributing to their breathing difficulties, weight loss may help reduce breathlessness and improve exercise tolerance. The effect will depend on the individual and whether other respiratory or cardiovascular conditions are also contributing to their symptoms.
Obesity is associated with several respiratory problems, including obstructive sleep apnoea, obesity hypoventilation syndrome and asthma. It can also affect lung mechanics and make breathing during physical activity more difficult.
Seek medical advice if breathlessness is new, worsening, occurring during normal everyday activities or affecting your quality of life. Breathlessness has many possible causes, so appropriate assessment can help determine what is responsible.
Medical References
- Asthma + Lung UK – Staying a healthy weight. Particularly relevant to the core subject of the article. It explains that excess fat around the neck, chest and abdomen can make deep breathing more difficult and increase breathlessness during everyday activities. Asthma + Lung UK – Staying a healthy weight
- NHS – Sleep apnoea. Supports the association between obesity and obstructive sleep apnoea, as well as the sections discussing symptoms, weight management and CPAP treatment. NHS – Sleep apnoea
- NHS – Overweight and obesity in adults. Supports the general discussion of obesity, health risks, gradual weight loss, physical activity and weight-management approaches. NHS – Overweight and obesity in adults
- British Thoracic Society – Clinical Statement on Pulmonary Rehabilitation. Useful supporting clinical guidance for the article’s discussion of breathlessness, exercise capacity and management of symptomatic chronic respiratory disease. British Thoracic Society Clinical Statement on Pulmonary Rehabilitation
