Temperature sensitivity, or temperature intolerance, is an unusual reaction to heat or cold that most people would find comfortable. This experience is not a disease itself but is often a symptom of an underlying issue within the body. A person with this condition might feel intensely hot in mildly warm environments or excessively cold when others are not.
The Body’s Thermostat
The human body maintains a stable internal temperature through thermoregulation, a process governed by the hypothalamus. This brain region acts like a thermostat, receiving information and making adjustments to keep the body’s core temperature around 98.6°F (37°C). It balances heat production and heat loss to ensure organs can function correctly.
Nerve receptors in the skin detect external temperature changes and send signals to the hypothalamus. If the body is too hot, it signals sweat glands to produce sweat, which cools the skin as it evaporates. It also causes blood vessels near the skin’s surface to dilate, or widen, allowing more blood to flow to the surface and release heat.
If the body is too cold, the hypothalamus triggers responses to conserve and generate heat. Blood vessels near the skin constrict, reducing blood flow to the extremities and keeping warmth closer to the vital organs. The hypothalamus can also signal muscles to start shivering, a rapid contraction that generates heat. The body’s metabolism also plays a part by producing heat as a byproduct.
Medical Causes of Temperature Dysregulation
Several medical conditions can interfere with the body’s temperature control system, leading to either heat or cold intolerance. Problems with the thyroid gland, for instance, are a common cause. Hyperthyroidism, an overactive thyroid, speeds up the body’s metabolism, causing individuals to feel hot and sweat excessively. In contrast, hypothyroidism, an underactive thyroid, slows metabolism, which can make a person feel persistently cold.
Neurological conditions can also disrupt thermoregulation. Multiple Sclerosis (MS) can damage the nerves that transmit signals between the brain and the body. This damage can interfere with the brain’s ability to initiate sweating or shivering, with up to 80% of MS patients experiencing heat sensitivity. Diabetes can damage blood vessels and nerves that control sweat glands, impairing the body’s ability to cool down.
Anemia, a lack of healthy red blood cells, can cause cold intolerance because there isn’t enough oxygen being delivered throughout the body. Raynaud’s phenomenon causes blood vessels in the fingers and toes to spasm and constrict in response to cold, leading to feelings of numbness and coldness in those areas. Fibromyalgia, a chronic pain condition, can also be associated with sensitivity to both heat and cold.
Lifestyle and Medication Influences
Age is a significant factor; infants and older adults have a harder time regulating their body temperature compared to other age groups. Body composition also plays a role, as individuals with very little body fat may find they are more prone to feeling cold because fat provides a layer of insulation.
Dehydration can make it more difficult for the body to cool itself through sweating, increasing sensitivity to heat. Chronic lack of sleep can also affect the hypothalamus and its ability to regulate temperature effectively. Excessive alcohol use can interfere with temperature regulation by causing blood vessels in the skin to widen, leading to heat loss.
Certain medications can disrupt the body’s thermoregulation as a side effect. Diuretics increase urination and can lead to dehydration, making one more susceptible to heat. Beta-blockers, used for heart conditions, can reduce blood flow to the skin, impairing the body’s ability to release heat. Some antidepressants and antipsychotics can either increase sweating or reduce it.
Managing Symptoms and Seeking Medical Advice
If you are sensitive to cold, layering clothing is an effective way to trap heat. Wearing a hat, gloves, and warm socks can help, as a significant amount of body heat is lost through the head and extremities. Consuming warm beverages and hot foods can also help to raise your core body temperature.
For individuals who struggle with heat intolerance, wearing loose-fitting, lightweight, and light-colored clothing can help the body stay cool. Staying well-hydrated by drinking plenty of water is important, as is avoiding strenuous activity during the hottest parts of the day. Using fans, air conditioning, or taking cool showers can provide immediate relief.
Consult a healthcare professional for a new or worsening temperature sensitivity, especially if it is accompanied by other symptoms. These can include:
- Unexplained weight changes
- Persistent fatigue
- Changes in heart rate
- Dizziness
- Significant mood alterations
A doctor can help determine the underlying cause and recommend an appropriate course of action.