Being overweight can have consequences for many different aspects of your health, including your respiratory health.
While it is easy to see the impact of excess weight on the shape and size of our bodies, many people fail to realise that obesity also affects the internal organs, including the lungs. These include mechanical, metabolic and inflammatory factors.
If you are carrying too much weight, your lung function can be affected. You may experience reduced lung capacity or breathing difficulties, due to an accumulation of fat around the chest and abdomen which can prevent your lungs from expanding fully and restrict movement of the diaphragm. Many people may also experience breathlessness, particularly during physical activity. There is also a certain amount of stigma associated with obesity which can make it less likely for individuals to exercise and may also affect a person’s mental health.
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.
What is the extent of the problem?
In 2022, The Lancet published a study showing that more than a billion people around the world are obese [2]. In the UK, according to a report published by the UK Parliament in January 2023 [3], estimates suggest that more than a quarter (26%) of adults are obese and a further 38% are overweight. As obesity rates have increased, so too have respiratory diseases linked to excess weight.
Treatments for managing respiratory diseases linked to obesity
Respiratory consultant, Dr Shalin Diwanji recommends a multifaceted approach to treatment, focusing on addressing both the underlying issue (obesity) and the respiratory conditions that can occur as a result. Weight loss strategies and lifestyle changes – such as exercising regularly and following a healthy eating plan – can help to relieve symptoms and improve lung function. Physiotherapists and dieticians offer specialist support in these areas. In some cases, a patient may be offered bariatric surgery to assist with significant weight loss.
Among the medical interventions available are anti-inflammatory medications to help manage COPD symptoms and bronchodilators for people with asthma. Obstructive sleep apnoea may be treated using continuous positive airway pressure (CPAP) therapy. A patient may also be referred to a specialist sleep clinic.
Frequently Asked Questions
There are clear indicators that carrying excess weight increases your risk of developing certain respiratory conditions, or of experiencing more severe symptoms.
The most effective approach to treatment addresses both the underlying cause and treats the symptoms. This is why we recommend weight-loss strategies and lifestyle changes alongside medical interventions.
If you are experiencing breathing difficulties or sleep-related breathing problems, you may benefit from assessment by a respiratory consultant.
Sources
[1] Bai, Y., et al. (2020). The relationship between obesity and asthma: a systematic review. Journal of Asthma, 57(10), 1020-1029.
[2] Phelps, Nowell H et al. Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults. The Lancet, Volume 403, Issue 10431, 1027 – 1050
[3] House of Commons Library. Obesity Statistics Carl Baker. 12 January 2023



