Chills in older adults stem from a combination of age-related body changes and underlying health conditions, some harmless and some serious. The body’s ability to regulate temperature declines with age, and older adults naturally run cooler, with a typical body temperature range of 96.4°F to 98.5°F compared to the commonly cited 98.6°F. That lower baseline means the threshold for feeling cold or experiencing chills is lower too, and a wider range of triggers can set them off.
How Aging Changes Temperature Regulation
The body produces less heat as it ages. Basal metabolic rate, the energy your body burns at rest to maintain core functions, declines steadily over the decades. Since metabolism is one of the body’s primary heat sources, this slowdown means less internal warmth. On top of that, the body’s thermogenic capacity (its ability to ramp up heat production when needed) also decreases. These two changes together place older adults at a significantly higher risk of feeling cold and developing chills even at room temperature.
Skin also thins with age, and subcutaneous fat, the insulating layer just beneath the skin, tends to redistribute or diminish. This makes it harder to retain the heat the body does produce. Blood vessels near the skin’s surface become less responsive, meaning the body is slower to constrict them in cold conditions, a reflex that normally preserves core warmth. The net result is that an older adult sitting in a 63°F room may start shivering while a younger person in the same room feels perfectly comfortable.
Infections That Don’t Look Like Infections
One of the most important things to understand about chills in older adults is that they can signal an infection, even when no fever is present. Aging blunts the body’s temperature response to infection, so the classic pattern of fever plus chills that younger people experience often doesn’t apply. An older adult can have a serious bacterial infection in their bloodstream and never spike a fever.
Urinary tract infections in older adults frequently show up as confusion or agitation rather than the burning and urgency younger people feel. Pneumonia in this age group is more likely to cause generalized weakness, falls, and low oxygen levels than the expected fever and chest pain. This makes chills especially worth paying attention to: they may be the body’s only visible signal that something infectious is going on. When chills appear alongside new confusion, unusual fatigue, a sudden decline in function, or a fall, the combination points toward a possible infection that needs prompt evaluation.
Hypothyroidism and Cold Sensitivity
The thyroid gland controls metabolic rate, and when it underperforms, the body generates less heat. Hypothyroidism is common in older adults. The Framingham Study found that 4.4% of adults over 60 had clear thyroid deficiency. Subclinical cases, where the gland is struggling but lab values haven’t crossed into the overtly abnormal range, are even more prevalent.
Cold sensitivity is one of the hallmark symptoms. In studies comparing people with and without hypothyroidism, feeling “colder” was reported significantly more often in the hypothyroid group. The tricky part is that hypothyroidism develops gradually, and its symptoms (fatigue, weight gain, constipation, dry skin, feeling cold) overlap heavily with changes people often dismiss as normal aging. A simple blood test measuring thyroid-stimulating hormone can confirm or rule it out, and treatment typically resolves the cold sensitivity.
Poor Circulation and Vascular Disease
Peripheral artery disease (PAD) narrows the blood vessels that supply the legs and feet, reducing blood flow to the extremities. It affects a large portion of adults over 60 and produces symptoms that can feel like chills localized to the lower body: cold skin, numb or cold toes, and a general sensation of chill in the legs. Some people describe it as their feet never warming up, regardless of socks or blankets.
PAD-related coldness tends to be most noticeable in one leg or foot, or more pronounced on one side. It often accompanies pain or cramping while walking that improves with rest. Heart failure and other cardiovascular conditions can also reduce overall circulation enough to cause a persistent feeling of being cold, since the body prioritizes blood flow to vital organs at the expense of the skin and extremities.
Indoor Temperature and Hypothermia Risk
Older adults can develop hypothermia inside their own homes, something many families don’t realize. The National Institute on Aging recommends keeping indoor temperatures at 68°F or higher for older adults. Even mildly cool homes in the 60 to 65°F range can trigger hypothermia in seniors, particularly those who are sedentary, have low body weight, or take medications that affect circulation.
This is a practical point worth acting on. If an older person in your life frequently complains of chills at home, checking the thermostat is a logical first step. Space heaters, layered clothing, warm blankets, and warm beverages all help, but the ambient temperature of the living space matters most. Nighttime is particularly risky, since metabolism naturally dips during sleep and bedrooms are often kept cooler than living areas.
Medications That Affect Body Temperature
Several types of medication commonly prescribed to older adults can contribute to chills. Beta-blockers, used widely for high blood pressure and heart conditions, slow the heart rate and reduce circulation to the extremities, making people feel colder. Some blood pressure medications cause blood vessels to dilate, which allows more heat to escape through the skin. Sedatives and certain psychiatric medications can interfere with the brain’s temperature-regulating signals.
If chills started or worsened after a medication change, that timing is worth noting and bringing up with a prescriber. The fix is sometimes as simple as adjusting a dose or switching to a different drug in the same class.
When Chills Signal Something Urgent
Because older adults often don’t mount a fever in response to infection, chills paired with certain other symptoms deserve prompt medical attention. The combination to watch for includes chills along with new or worsening confusion, rapid breathing, extreme fatigue or sudden inability to perform normal activities, a fall, or skin that looks mottled or unusually pale. These patterns can indicate sepsis or another serious infection progressing without the usual warning signs.
Chills that come and go with cold exposure or happen in a cool room are usually a thermoregulation issue. Chills that persist regardless of warming measures, come on suddenly without an obvious trigger, or accompany a noticeable change in mental status or energy level are the ones that warrant a closer look. In older adults, the absence of fever does not rule out infection, and that single fact changes how chills should be interpreted in this age group.