The thyroid is most known for its influence over the metabolism and subsequently energy level, weight regulation and mental focus. However, many are not aware that thyroid dysfunction and suboptimal hormone levels can affect other aspects of health.
Because every tissue in the body has thyroid receptors, thyroid hormones can impact a wide array of bodily functions. A lesser known symptom of hypothyroidism is labored breathing and poor respiration. People may also know this as air hunger or dyspnea.
Understanding how the thyroid influences respiratory ability and what breathing difficulties are associated with thyroid dysfunction may improve diagnosis and treatment of existing or future breathing issues.
Is My Thyroid the Problem?
There are multiple documented medical studies that contain reports of hypothyroid patients, or those with thyroid hormone resistance, experiencing breathing difficulties.
Thyroid-related breathing issues may present themselves in a variety of ways. Some patients only develop air hunger after exertion whereas others may have difficulty getting enough air even while at rest.
Shallow breathing from the chest region is also an indicator of greater respiratory dysfunction that is commonly seen among those with air intake difficulties.
The thyroid impacts respiration in multiple ways. Respiratory weakness due to poor thyroid hormone regulation may result in significant air hunger. Ideally the diaphragm does most of the work needed to get air into the lungs. Reduced hormone levels can cause an energy deficiency in the diaphragm making it incredibly difficult for a person to acquire enough air. In this case, the body must rely on other muscle groups and systems to breathe. This is often identified by inward movement of the stomach rather than typical cavity expansion. Instead of opening up and allowing air to enter, this inward action opposes and inhibits the diaphragm’s ability to create a vacuum in the lungs for proper air intake.
Limited thyroid function can also impair phrenic nerve functionality. The phrenic nerve regulates diaphragm contractions, which is responsible for air intake. When not working properly, the phrenic nerve produces a signal that is too weak to trigger appropriate diaphragm contraction, which belabors breathing. Resolving thyroid hormone imbalance may alleviate this issue.
Another aspect of respiration impeded by poor thyroid function is the central drive. The central drive of respiration involves neurological processes that regulate breathing. Many are familiar with the neurological dysfunction associated with hypothyroidism. Similarly, thyroid hormone deficiency can cause neurological issues resulting in decreased air intake and poor respiratory regulation.
Even lower degree hypothyroidism may cause a patient to suffer from breathing issues.
A small study, requiring additional research and a larger test group to validate their findings, investigated the connection between hypothyroidism and respiratory function. Of the ten hypothyroid participants in the study, it was found that two of them had a limited response to hypercapnia. Hypercapnia is the retention of carbon dioxide resulting in an increased concentration in the bloodstream. This can be harmful and usually triggers greater oxygen intake. Interestingly, the two hypothyroid participants affected by hypercapnia did not exhibit the appropriate response of increased respiration to clear the excess carbon dioxide from their system. However, after being treated with thyroid hormones, the patients’ breathing returned to a healthy level.
Respiratory Conditions Associated with Hypothyroidism
In addition to the typical symptoms of hypothyroidism such as weight gain, depression and fatigue (get the full thyroid symptom list here), there is a collection of breathing issues that can be caused by poor thyroid function or reduced hormone levels.
The following conditions have been associated with hypothyroidism:
- Diaphragm dysfunction
- Inhibited respiration due to low central nervous system drive
- Airway obstruction
- Pleural effusion
- Sleep apnea
Although there are multiple reasons why these conditions develop, optimizing thyroid levels may provide relief. In a small study composed of hypothyroid patients, it was found that 25 percent of them had sleep apnea. Generally, sleep apnea was exhibited in the older and more obese individuals. The correlation of reduced thyroid function and the occurrence of sleep apnea is something to consider if suffering from breathing difficulties that disrupt sleep. However, it is important to keep in mind that even though hypothyroidism may often cause sleep apnea, not all patients with sleep apnea have thyroid issues. Regardless, if a person is experiencing difficulty breathing it may be beneficial to assess their thyroid function.
The Positive Influence of Thyroid Therapy on Respiration
A 1991 study showed that treating asthmatic children with T3 (the active form of thyroid hormone) proved to be beneficial. Even though the 23 participants were not hypothyroid, the 30-day thyroid treatment provided positive results. The subjective response from the children was an improvement of their overall asthmatic condition and reduced frequency of asthma attacks. Seven of the participants actually remained on the T3 treatments and ceased their typical anti-asthmatic medication. The researchers reported that all participants responded well to T3 treatment and did not experience any negative side effects.
Those with a breathing condition may benefit more from thyroid replacement therapy than traditional inhalant treatments. Typical inhalants for asthma and other respiratory conditions stimulate beta2-adrenergic receptors located in the bronchial tubes. This triggers dilation of the tubes that compresses blood vessels thereby drying mucous secretions. This is the common mechanism used to alleviate asthmatic issues such as shortness of breath, coughing and wheezing. Interestingly, thyroid hormone therapy increases the prevalence of beta2-adrenergic receptors in the bronchial tubes, which can improve the efficacy of inhalants and possibly get a person off of traditional respiratory treatments.
Breathe Easy by Supporting Your Thyroid
If you are suffering from breathing issues such as air hunger, asthma or even sleep apnea, they may be caused by thyroid dysfunction. If you are already being treated for a thyroid condition, speak with a physician about optimizing your treatment. If not, consider having your thyroid tested – click here for a printable lab slip.
Keep in mind that thyroid testing standards frequently overlook thyroid deficiency. TSH testing alone is not adequate to identify thyroid dysfunction. It is best to pursue a comprehensive thyroid test that includes TSH, Free T4, Free T3, T3 uptake and thyroid antibodies to uncover any possible thyroid-related contributors to breathing difficulties.
Appropriately supporting the thyroid may be the best method for restoring respiration.