Autoimmune diseases like lupus and thyroid conditions often disrupt body temperature regulation because of autoantibodies’ effects on metabolism, inflammation, and the nervous system.
Unfortunately, autoimmune diseases are both unique and complex, so each condition requires its own explanation. In hypothyroidism, for example, a reduced metabolism leads to cold intolerance, while hyperthyroidism, which speeds up metabolism, often results in heat intolerance. In lupus patients, however, the answer is less straightforward. Lupus patients frequently report heat sensitivity, which is associated with inflammatory factors during flare-ups. In multiple sclerosis, symptoms worsen in high temperatures because heat temporarily disrupts communication between already damaged neurons.
Thyroid disorders and temperature intolerance
Autoimmune thyroid disorders, like Hashimoto's and Graves’ Disease, provide a good example of how autoantibodies can ultimately affect temperature regulation.
In patients with Hashimoto's thyroiditis, the immune system attacks the thyroid gland, which is a key mediator of metabolism. This attack disrupts thyroid function and, in turn, metabolism. A slower metabolism means that it takes longer to use energy. Using energy creates heat as a byproduct, so less energy used means there’s less heat produced. Because they give off less heat, many people with Hashimoto’s feel cold even in mild weather.
On the other hand, in hyperthyroid conditions, like Graves’ disease, metabolism is accelerated by autoantibodies that stimulate the thyroid response. This leads to increased heat production and sensitivity to warmer environments, making it harder to cool down.
Lupus and heat intolerance
Heat sensitivity in lupus, otherwise known as SLE, or systemic lupus erythematosus, stems from lupus patients' increased susceptibility for fever. During a lupus flare, there are more inflammatory factors produced, which are ultimately responsible for fevers, and therefore, overheating.
Lupus patients are also more vulnerable to low-grade infections than healthy individuals because they’re immunocompromised. This leads to more instances where their bodies induce a fever to fight off infection.
Multiple sclerosis and heat intolerance
Patients with multiple sclerosis (MS) are heat intolerant because heat temporarily disrupts the communication between demyelinated neurons. Demyelination is the main trait that defines MS–it refers to the breakdown of the insulating layer around neurons that helps with quick signal transmission. When MS patients overheat and neural communication is disrupted, their cognitive function is altered, but generally for less than 24 hours. This is referred to as Uhthoff’s phenomenon, which became one of the first diagnostic tools for MS. This test involved submerging patients in hot baths and assessing whether they experienced cognitive decline. Today, however, there are more advanced (and less intrusive) ways of diagnosing MS.
Medications and body temperature regulation
Medications used to treat autoimmune diseases can affect patients' body temperature regulation. Steroids, commonly prescribed for conditions like lupus, Sjögren's, and Hashimoto's, reduce inflammation and control immune activity. While effective, certain steroids can increase body temperature as a side effect by boosting metabolic processes. These include glucocorticoids (a type of steroid) such as prednisone.
The bottom line
Autoimmune diseases don't just impact the immune system—they also wreak havoc on how your body manages temperature fluctuations. Conditions like Hashimoto’s and Graves' disease directly affect metabolism, altering the body's ability to generate or shed heat. Lupus, however, disrupts temperature regulation through inflammation, and MS patients respond poorly to high temperatures due to nerve damage. The relationship between autoimmune disorders and body temperature is as complex as the diseases themselves, making personalized care essential. Understanding these mechanisms can empower patients to manage their symptoms more effectively, especially in challenging climates.
