If you feel like you’re always cold, it may be because of a condition known ascold intolerance.
Cold intolerance is not an illness but simply an abnormal sensitivity or hypersensitivity to cold environments or cold temperatures.
You may have an exaggerated reaction to cold, causing discomfort and/or the avoidance of cold.
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The causes ofcold intoleranceare varied and often due to a variety of issues.
Thyroid Disease
Hypothyroidism, or low thyroid function, is one of the most recognized causes of cold intolerance.
In a cold environment, thyroid hormones can increase metabolism to help normalize your body temperature.
Estrogen
Estrogenis a hormone that regulates female reproduction.
Estrogen levels change throughout life.
including during the menstrual cycle, pregnancy, and menopause.
Fluctuating estrogen levels can increase cold sensitivity, particularly as females reach the end of their reproductive years.
The same fluctuations may explain why some people experience cold intolerance right before the start of their period.
Thelutealphase, which occurs right after ovulation, is when estrogen levels are at their peak.
These extreme hormonal changes can lead to symptoms like increased coldness and shivering.
Anemia
Anemiais a condition in which you don’t have enoughred blood cellsto transport oxygen through the body.
Iron deficiency anemiais a bang out of anemia brought on by the lack of iron in the body.
The abnormal constriction of blood vessels deprives the tissues of oxygen.
This, in turn, reduces the skin temperature and increases its sensitivity to cold.
Other symptoms include numbness, tingling, or throbbing pain.
Reynaud’s syndrome is treated by managing the underlying cause, if any.
It also includes avoiding cold, stress, and smoking (which increases vasoconstriction).
Anorexia
Anorexia nervosa, or simply anorexia, is an eating disorder characterized by a limited food intake.
People with anorexia often eat so little that they cannot sustain basic bodily functions.
With that said, low body weight is inherently linked to lesssubcutaneous body fat.
This is the layer of fat tissue just below the skin.
The loss of this insulating layer increases the risk of cold intolerance.
In addition to reducing subcutaneous fat, low body weight is linked to an increased risk of anemia.
Diabetes
Diabetesis a group of diseases that causes excess glucose (sugar) in the blood.
Medications
Certain medications can cause cold sensitivity.
They do so by either impeding blood circulation or damaging nerves that regulate skin sensations.
The classes of drugs commonly associated with cold sensitivity include:
9.
The reduced blood flow triggered by PAD can increase cold sensitivity in the same way as vasoconstriction.
This can lead to nerve pain that further exaggerates a person’s response to cold.
Severe cases may requirevascular surgery.
Sleep deprivationdisrupts this process.
This promotes heat loss from the feet and hands, making them feel colder.
This, in turn, interferes with the release of certain hormones that regulate sensory nerves in the skin.
Sleep deprivation can be treated with improved sleep practices (referred to assleep hygiene) and medications.
Nerve Issues
Cold intolerance can occur when the peripheral nerves are damaged.
This typically pops up if the insulated coating on nerves, called themyelinsheath, is damaged or stripped away.
This can cause nerve cells to misfire, triggering shock-like pain, numbness, tingling, or burning.
You may even experiencechillsand shivers, known asrigors, that are so intense that you cannot stop.
Feeling cold during an infection is largely due to the consumption of extra energy to help fight the infection.
Rigors, on the other hand, are triggered by the presence of chemicals calledpyrogensin the blood.
The immune system produces pyrogens to raise the body’s temperature to help fight infection.
But, they can trigger a contradictory reflex resulting in severe shivering and chills.
Chills are triggered by the rapid contraction and relaxation of muscles that aim to bring the body temperature up.
Bacterial infections may resolve on their own or require antibiotics.
This, in turn, can lead to cold intolerance by slowing down the body’s response to cold.
Because the body does not respond as quickly, the person may feel cold far more intensely than others.
Vitamin B12 Deficiency
Vitamin B12 deficiency can cause you to feel cold.
This can cause a decrease in core body temperature, which may cause you to feel colder.
There is much variation in the sensitivity to cold that different people experience.
Some may only shiver and put their hands in their pockets in response to the cold.
Others may require layers of clothes to keep warm.
Cold intolerance occurs at temperatures that are otherwise tolerable to others in that environment.
However, intolerance to cold that is new or gradually worsening may require evaluation.
Diagnosis and treatment of the underlying condition can help improve your symptoms, including cold sensitivity.
Summary
Cold intolerance is an abnormal or exaggerated reaction to cold exposure.
It can occur when a person’s body temperature is persistently lower due to any number of medical reasons.
Or, it can happen when a person’s body temperature is normal but they perceive cold differently.
Often, multiple causes are involved.
Even certain medications or the lack of sleep can trigger intolerance to cold.
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