Hot applications are frequently used in physical therapy . People with long-term complaints due to joint calcification (osteoarthritis) often say that their pain increases in cold and humid weather, while heat is good. Heat therapy also has a place in fibromyalgia, muscle spasm, low back and neck pain. However, some people do not like the heat. In a hot environment, their pain increases and they may feel worse. In fact, while other people in the same environment are quite comfortable, people with heat sensitivity find the environment warm. They may express that they feel relieved when they put their hands and feet on a cold place. Rarely, heat sensitivity can pose a risk for life-threatening heat stroke. So what does it mean to dislike the heat and make the cold feel better?
Being more uncomfortable in a hot environment than other people is called heat intolerance. Heat intolerance may reflect an abnormality in regulating body temperature. Our body keeps the internal temperature at a constant value, whether the environment is hot or cold, through various mechanisms. The hypothalamus in our brain is the center that regulates body temperature. When the temperature rises, signals from the hypothalamus increase sweating. The temperature is reduced by sweating (evaporation).
The hypothalamus is the director of the autonomic nervous system. Defects in this system (dysautonomia) may occur due to diabetes, excessive alcohol consumption, Parkinson’s disease, Guillain-Barré syndrome, and mitochondrial diseases.
What are the Symptoms of Heat Intolerance?
The person may feel excessively hot even though the ambient temperature is normal. Excessive sweating is also common. Sometimes, despite the hot environment, there may not be enough sweating. Complaints such as headache, dizziness, muscle weakness, weakness, muscle cramps, nausea, palpitations may occur.
Heat intolerance can lead to heat exhaustion in severe cases. Loss of consciousness, vomiting, muscle cramps, elevated body temperature (40 degrees or more), accelerated pulse, increased respiratory rate may indicate heat exhaustion. In this case, it is necessary to seek immediate medical help. If left untreated, heat exhaustion can progress to heatstroke, which can be fatal.
What Causes Heat Sensitivity?
One of the causes of heat sensitivity is the drugs used by the person. Allergy drugs, drugs used to open nasal congestion, some hypertension drugs can cause heat sensitivity. Allergy medications can prevent sweating, making it harder for the body to cool itself. Hypertension medications can reduce skin blood flow, which can reduce sweating. Cold medications called decongestants can increase body temperature by both reducing skin blood flow and increasing muscle activity. Some psychiatric and neurological drugs can also cause heat intolerance.
Caffeine in coffee increases heart rate and metabolism. This can increase body temperature and cause sensitivity to heat.
Overworking Thyroid Gland – Hyperthyroidism
If the thyroid gland, located in the front of our neck and known for goiter, produces too much hormone, a condition called hyperthyroidism may occur. Metabolic rate increases in hyperthyroidism. As the body temperature increases, the person may feel uncomfortable in a hot environment.
Multiple sclerosis (MS disease) is a chronic neurological disease that can affect the brain and spinal cord. It is characterized by damage to the insulating layer around the nerve fibers. MS disease symptoms can flare up in a hot environment. This is called the Uhthoff phenomenon. Vision problems (blurred vision, vision loss) may occur.
Children under 4 years old and the elderly are more sensitive to heat.
Sensitivity to heat can be seen during menopause.
What to do?
People with heat sensitivity should be careful to stay in a cool environment. It should not be exposed to direct sunlight and should stay in air-conditioned environments in hot weather. Drinking plenty of water is necessary to compensate for fluid loss due to sweating. Lightweight cotton clothing that allows air circulation helps to cool the body. Intense physical activities should be avoided in hot weather. Being overweight can make it difficult to reduce body temperature, so being at a normal weight is beneficial. If heat sensitivity is due to hyperthyroidism or another disease, treatment of the disease may reduce the symptoms.