What’s really going on when people say their body ‘runs hot’ or ‘cold’

Is it hot in here or is it just you?

Naturally “running hot” or “running cold” has been the center of debates in households and offices since the advent of air conditioning, as battles over thermostats rage on amid the summer’s heat waves.

While some may chalk it up to the weather, doctors have revealed regulating body temperature is not just skin-deep.

“I think the first thing just to understand is that humans can regulate their body temperature, regardless of their environment,” Dr. Heather Viola, who works in internal medicine for New York’s Mount Sinai Health System, told HuffPost.

“And where that starts is with your autonomic nervous system,” she continued, explaining that it “controls automatic functions” such as sweating and breathing.

There, “hormones are released to control temperature.”


Neurons
Part of the nervous system controls how the body regulates internal temperature.
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Stress levels, smoking, muscle mass and diet all play an integral role in body temperature, she added.

“A lot of people, when they’re under stress, can definitely perceive that they’re more hot than those around them,” Viola said.

“I think the same thing can be said for if you consume spicy food, or caffeine or even a lot of alcohol, it can also affect your autonomic nervous system and raise your heart rate.”

Additionally, more body fat keeps people insulated.

“This may be why a lot of older people feel colder than younger people,” Viola said. “Just because the fat layer under the skin that conserves heat can thin as people get older.”

Certain medications could also cause people to feel flushed, and biological sex is also a factor.


Man feeling hot basking in fan's breeze
Feeling flushed could be due to genetics, medication or a health condition.
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Women often “run colder” than men due to having a naturally higher core temperature, which could be caused, in part, by hormones or hormonal contraceptives, according to data compiled by Glamour.

Having a higher core temperature makes people more susceptible to feeling chilly in colder environments — like when the air conditioning is dialed up in the office.

What is supposed to be “hot girl summer” rapidly descends into “women’s winter,” according to the shuddering employees holed up in their frigid cubicles.

But issues with body temperature regulation could also be due to an underlying medical condition, according to Dr. John Schumann, the executive medical director of Oak Street Health in Oklahoma.

Low thyroid hormone levels could usher in the big chill rather than the sweats, he told HuffPost, but high thyroid levels could result in the opposite effect.


Woman shivering in blanket
Certain foods or even caffeine can alter body temperature.
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Anemia — when the body does not produce enough red blood cells or enough iron — could also result in feeling “cold all the time,” he added.

Diabetes, menopause, anxiety, cancer and fibromyalgia could also affect body temperature.

But feeling overly hot or cold isn’t a reason to rush to the doctor. Typically, a worrisome medical condition would result in other symptoms as well.

“It doesn’t always come down to a medical condition,” Viola said.

“I wouldn’t say somebody runs hot for no reason,” she added. “I would say there [are] underlying reasons physiologically, and usually comes down to your body habits.”