Why Am I Always Cold? 9 Reasons Why You Can't Stop Shivering

It's normal to feel cold in colder climates. Maybe your hands and feet especially have a tendency to feel frigid. But if you notice that you're constantly feeling cold, even when you're not in colder temperatures, there may be an underlying cause. Here are nine possible reasons why you're always feeling cold.

1. Low Body Weight

Low body weight—which the Centers for Disease Control and Prevention (CDC) defines as having a BMI below 18.5 kg/m²—can keep you feeling cold for a couple of reasons.

First, when you're underweight, you lack an adequate level of body fat to insulate you from cold temperatures, Maggie Moon, RD, a Los Angeles–based nutritionist, told Health.

Plus, a low BMI may mean that you have less fatty tissue, which, according to a 2022 study published in the EPMA Journal, can cause your body to produce less heat.

Because having a low body weight may also mean you have low muscle mass, that could also be contributing to your chilliness. That's because muscle helps maintain body temperature by producing heat, Margarita Rohr, MD, an internist at NYU Langone Medical Center in New York City, told Health.

What to do: If you're underweight, talk to your healthcare provider, who will run tests to see what's causing your low body weight. Healthcare providers may also suggest you put on a few pounds by loading up on whole, healthy foods that contain protein, fat, and complex carbohydrates. And hitting the weight room at the gym or investing in free weights can help build muscle.

2. Hypothyroidism

"Always being cold is a telltale sign of hypothyroidism, which means your thyroid doesn't secrete enough thyroid hormone," Holly Phillips, MD, a board-certified internist with a private practice in New York City, told Health. Without the right level of this hormone, your metabolism slows, preventing you from generating adequate heat.

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) states that nearly 5% of Americans have this condition. Rates are higher in females and those who are over age 50 years, according to MedlinePlus. MedlinePlus notes that signs of hypothyroidism include:

• Thinning hair or hair loss
• Dry skin and hair
• Irregular or heavier periods
• Unexplained weight gain

What to do: If you suspect a thyroid problem, see your healthcare provider, who can confirm the diagnosis with a blood test and treat the condition appropriately.

3. Iron-Deficiency Anemia

Low iron levels are one of the most common reasons for chronic coldness. That's because iron helps red blood cells carry oxygen throughout your body, so it's able to produce heat, Dr. Phillips explained. Iron is also crucial because a deficiency can slow thyroid functioning, leading to hypothyroidism—which can further leave you feeling cold, Moon said.

According to the National Heart, Lung, and Blood Institute, other symptoms of low iron levels include:

• Pale skin
• Brittle nails
• Difficulty concentrating
• Shortness of breath

What to do: First, you'll want to get a proper diagnosis via a blood test. Then, depending on the severity of your anemia, your healthcare provider may suggest you take iron supplements, get an IV infusion, or boost your intake of iron-rich foods like red meat, leafy greens, and eggs, Moon said.

4. Poor Circulation

If your hands and feet feel cold, but other parts of your body feel warm, a circulation problem that keeps blood from reaching your extremities may be the reason.

One common cause of circulation problems is Raynaud's disease, sometimes called Raynaud's phenomenon. Primary Raynaud's disease, which doesn't develop due to another disease like secondary Raynaud's disease does, affects about 10% of the population, according to the American College of Rheumatology.

This condition causes the blood vessels in your hands and feet to temporarily narrow when they sense cold, Dr. Rohr said.

Other reasons blood may have a hard time reaching your limbs include cardiovascular disease, which causes your heart to not pump as effectively, or smoking, which constricts blood vessels, Dr. Rohr said.

What to do: Take a visit to your healthcare provider, who can determine if the cause of your circulation problems is due to Raynaud's disease. Healthcare providers can direct you towards a treatment plan and also ensure your symptoms are not something more serious like cardiovascular disease.

5. Dehydration

If you just can't warm up, it could be a sign that you need to drink more water. "Up to 60% of the adult human body is water, and water helps regulate body temperature," Moon said.

"If you're adequately hydrated, water will trap heat and release it slowly, keeping your body temperature in a comfortable zone. With less water, your body is more sensitive to extreme temperatures," Moon added.

Beyond feeling chilly, other symptoms of dehydration include:

• Dizziness
• Confusion
• Dry skin
• Tiredness
• Urinating and sweating less than normal
  
• Dark-colored urine
• Dry mouth

What to do: Aim for eight glasses of water a day at a minimum, Moon recommended, but always drink more if you're working out or spending time in the sun.

6. Vitamin B12 Deficiency

Not consuming enough vitamin B12—about 2.4. micrograms daily for the average adult—can cause anemia, resulting in chronic coldness, Moon said. According to MedlinePlus, symptoms of vitamin B12 deficiency include:

• Fatigue
• Diarrhea or constipation
• Loss of appetite
• Pale skin
• Feeling irritable
• Shortness of breath, usually during exercise
• Swollen, red tongue or bleeding gums

If vitamin B12 deficiency goes on for too long without being treated, it can also cause the following symptoms:

• Numbness or tingling in the hands or feet
• Confusion or change in mental status
• Problems concentrating
• Loss of contact with reality (psychosis)
• Loss of balance
• Hallucinations
  

What to do: While B12 deficiency is rare in the general population, it's common among vegans or vegetarians since the nutrient is almost exclusively found in animal products, Moon said. Therefore, try taking a supplement if you're plant-based. Otherwise, check in with your healthcare provider, as it may be a sign of an absorption issue.

7. Blood Sugar Conditions

Diabetes that's not kept in check can lead to a condition called peripheral neuropathy, which damages the nerves in your hands and feet, according to the American Diabetes Association.

"When this develops, you experience numbness and sometimes pain in the hands and feet, and since these nerves are also responsible for sending messages to the brain regarding temperature sensation, your hands and feet may feel cold," Dr. Rohr said.

When sugar levels in the blood drop too low—a condition otherwise known as hypoglycemia—you may experience chills. People with diabetes can have hypoglycemia if they take too much insulin or aren't eating enough carbohydrates for the amount of insulin they're taking. If you don't have diabetes, hypoglycemia may be due to:

• An imbalanced diet
• Going too long without eating
• Menstruation

People with hypoglycemia may also experience weakness, blurry vision, or confusion.

What to do: Diabetic nephropathy develops gradually, so you may not realize you have it. But if you have been diagnosed with or have symptoms of diabetes, like frequent urination, fatigue, and feeling parched, see your healthcare provider to determine the next steps.

If you think your blood sugar is low, the American Diabetes Association recommends having 15 grams of carbohydrates (equivalent to 4 ounces of juice or a tablespoon of honey) and checking your blood glucose level after 15 minutes (or seeing if you feel better, if you don't have diabetes). If it's still low, have another serving, and repeat these steps until your level is normal or you feel better. Contact a healthcare provider if you experience ongoing hypoglycemia symptoms.

8. Lack of Sleep

Not getting enough sleep wreaks havoc on your nervous system, which can alter your temperature regulating systems, Dr. Phillips said. Plus, when you're fatigued from a restless night, your metabolism works at a more sluggish pace, Dr. Phillips added. Having metabolic issues could also lead to feelings of coldness, according to MedlinePlus.

What to do: Make sure you're getting the recommended hours of sleep each night for your age. Adults need seven or more hours of sleep per night. Also, try sticking to a regular sleep schedule and powering off electronics about 30 minutes before you sleep.

9. Beta Blockers

If your hands and feet feel cold, it could be because you're taking a beta blocker, which is a class of medicines typically prescribed for heart and circulatory system issues. Beta blockers slow down the heart to improve blood flow and reduce blood pressure, and they may affect how much blood reaches your hands and feet.

What to do: If you suspect your beta block is to blame for your chilliness, reach out to a healthcare provider to discuss whether you should switch medications. In the meantime, keep your body parts warm with heavy gloves and socks.

A Quick Review

There can be several different reasons for why you may be feeling cold. If you've eliminated causes like lack sleep, dehydration, and low body weight and are still feeling cold, paying a visit to a healthcare provider may be your next step. A healthcare provider can help you determine what, exactly, has you feeling chilled.