You know the type: Some people always seem to feel chilled even during the dog days of summer -- and constantly wear a sweater, no matter how high the mercury rises. Why are some folks' internal body thermostats set at a lower level regardless of the outside or indoor temperatures? It's triggered countless arguments and thermostat feuds at workplaces, homes, and in the bedroom.
Of course, humans can't be physiologically cold-blooded. But Dr. Robert Schainfeld, a vascular medicine specialist at Massachusetts General Hospital in Boston, offers some possible reasons why some people seem to be cold, all the time.
Some explanations are commonsense: Thinner, frailer, slighter built people with smaller muscle mass and body mass tend to feel the cold more. They lack the body insulation -- the muscle and fat -- that holds heat in. Also, if you have a lower body weight and you're also feeling tired or sleep-deprived, there's a tendency for your regulatory mechanisms to go a little haywire, explains Schainfeld, making you feel colder.
The air may also feel nippier to older adults, people who are anemic (low blood counts), malnourished, or have an infection (viral or bacteria). Folks who have hypothyroidism (low levels of thyroid hormone) or are deficient in certain B-vitamins, including B-1 (thiamine), B-6 (pyridoxine), or B-12 (cobalamins) may complain they're freezing.
Blood sugar levels that are too low (hypoglycemia) or too high (from poorly controlled diabetes) may increase a person's sensitivity to cold. Although the effect is short-lived, when a person is stressed, or feels anxious, afraid, or in pain, an adrenaline boost shunts blood away from the body's outer reaches and toward the heart and other vital organs, leaving you feeling chilly.
Of course, some places crank up the AC so high that the arctic air would give the heartiest among us goose bumps.
But a small percentage of people who are super sensitive to the cold have Raynaud's, a disorder in which there's an over-exaggerated constriction of blood vessels so less blood -- and warmth -- flows to the fingers, toes, earlobes, and tip of the nose.
Cold-sensitive people tend to know it about themselves and likely come prepared, carrying along extra layers to weather the elements -- indoors or out.
According to Schainfeld, you rarely find a reason in people who always feel cold and it's usually "a nonspecific benign problem." When he has discussed it with a patient, Schainfeld hears a common response, "I've been this way all my life, doc."
Have you been sensitive to cold your whole life, too? How do you handle it?
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