This week a “” slammed the East Coast of the United States, putting millions of Americans under blizzard warnings.

If you’re lucky enough to be able to stay put — and aren’t one of the thousands who have already lost their power — you can watch this winter show from the comfort of your warm house or apartment. But the moment you venture outside, this kind of extreme weather can put your health at risk in a number of ways. 

For those who haven’t really lived through a harsh winter, extreme cold is unlike anything you’ve ever experienced.

Just ask Jennifer McCallum, a writer and composer who spent a year living in Antarctica, where the temperature during the third week of October was –65˚F (–54˚C) and later dropped to –107˚F (–77˚C).

“When I stepped off the plane onto the Antarctic Plateau, the cold greeted me like angry black flies with razor-blade teeth,” McCallum told Dr.China. “I quickly learned to not directly breathe in the air, which would burn my lungs.”

She and scientist John Bird describe their experiences in the book “.”

But even less extreme cold weather can be harmful. Here are the top dangers.

Frostbite. This results from cold temperatures damaging parts of your body, most often your ears, nose, cheeks, chin, fingers, and toes.

Frostbitten skin may look white or gray and can feel hard or waxy. Blisters can form. You may also have trouble moving that part of your body. In severe cases, the skin will turn black.

Hypothermia. This condition occurs when your body temperature drops below 95˚F (35˚C). This results from your body losing more heat than it can make, such as when you are exposed to cold or water.

Hypothermia can show up as shivering, clumsiness, confusion, tiredness, or urinating more than usual. If not treated quickly, hypothermia can cause severe health problems, including death.

Heart problems. Cold weather can increase your risk of a heart attack. When you’re outside in the cold, your heart works harder to keep you warm — leading to increased heart rate and blood pressure.

This can cause , especially if you have an existing heart condition. If you aren’t used to regular exercise, strenuous activities like shoveling snow may put you at risk for a heart attack.

Less obvious effects

Getting lost in a whiteout. McCallum said whiteouts were a big challenge in Antarctica. “We once lost two electricians,” she said, “who fortunately found their way back.”

Even outside of Antarctica, blizzard-like conditions can make it impossible to find your way back to safety if you get lost.

Dry skin and mucus membranes. These are common in the winter. Winter air is usually quite dry, and that can suck the moisture out of your body.

Adam Gill, a weather observer and IT specialist for the Mount Washington Observatory, located on top of 6,288-foot Mt. Washington in New Hampshire, knows this all too well.

“Indoor relative humidity frequently falls down to 1 percent in the winter,” Gill told Dr.China. “If you don’t have a humidifier, then you wake up feeling like you are getting sick, but that will usually improve within a few hours of waking up.”

Balance. When it’s cold outside, there’s bound to be ice — which means more chances of falling and getting injured. Older people are more at risk of injury, but anyone can get hurt if they slip on icy sidewalks or stairs.

Strong winter winds can make it even harder to stay upright on ice. Check out this of Gill battling 100 mph winter winds on top of Mt. Washington.

Being sedentary. When cold weather goes on and on, you may end up binge watching television for days or weeks. This kind of sedentary behavior can increase your risk of obesity, heart disease, and other health issues.

“I have gotten more out of shape, since we cannot spend an extended amount of time outdoors in winter,” said Gill. “I do take advantage of nicer days and get outside for a while, but much less than in the summer.”

Loading up on snack foods. When the cold weather sets in, you may find yourself craving salty, sweet, or fat-filled comfort foods as your body tries to keep itself warm.

“Chocolate chip cookies were the favorite cookie at the station,” said McCallum. “And people experienced an incredible amount of stress over the need to ration chocolate chips.”

Staying safe in extreme winter

Living on top of the tallest mountain in the eastern United States, Gill knows how important it is to stay warm in the winter.

“Living here, especially in the winter, can be challenging, but with the right precautions it isn’t too bad,” said Gill. “All of the staff up here have to bundle up quite a bit before venturing outside — especially when the temperature starts to get down to –65˚F or colder — largely due to the consistent strong winds we see.”

McCallum spent many nights outside taking pictures of the sky over Antarctica, which meant dressing warmly… and creatively.

“We could be outside quite a while, as long as we had no skin showing,” said McCallum, “which involved artfully sealing ourselves with an assortment of head and neck coverings, goggles, and parka.”

Here are some tips to help you stay warm when the temperature plummets and the wind roars:

  • Wear several layers of lightweight and warm clothing so you can adjust as you warm up or cool down. Loose-fitting clothes trap warm air better than tight-fitting ones. The topmost layer should be water and wind resistant.
  • Mittens are always warmer than gloves. If you’re exercising, your hands may be warm enough with just gloves, but take along mittens or another pair of gloves that fit over those for when you stop moving.
  • Cover your head and face with a hat and scarf or mask to protect your skin. Wear sunglasses or goggles to protect your eyes.
  • Wear warm, waterproof boots with good tread to prevent slips and falls. If the ice is really bad, you can put traction cleats or crampons onto your boots.

Staying safe in extreme cold, though, also means thinking ahead.

“Beyond knowing how cold and windy it is, you need to plan what you will be doing outside, and how long you will be out,” said McCallum. “You also need to think about the quickest route back inside should you freeze your hands too much.”

She also said that if you go outside alone, let someone know where you’re going and when you’ll be back.

And pay attention to those you are with.

If you or someone else shows signs of hypothermia or heart or breathing problems, seek medical help immediately.

For frostbite, move to a warm place and take off any wet clothing. Use warm — not hot — water or body heat to warm the affected areas. Don’t rub the skin. If symptoms don’t get better, go to a hospital.

“If my fingers or toes went numb, I was quick to head inside and take care of them,” said McCallum.

Cold weather myths

Not everything you learned as a child about winter is correct. Here are a few of the most common myths.

Myth: Not wearing a coat will make you sick. While colds and flu are common in the winter, it’s not due to the weather. Some say cold viruses replicate better in cold weather, while others say frosty weather can dry out the mucous membranes in your nose.

Myth: You lose most of your heat from your head. Your head is just another extremity. A 2008 in The BMJ puts the heat loss from your head closer to 10 percent. So don’t try going outside in the winter with just a hat for protection.

Myth: You shouldn’t exercise outside when it’s cold. According to the , if you’re in good health, you shouldn’t have any trouble exercising outside in the winter — as long as you’re dressed appropriately. If you have heart, lung, or other health problems, check with your doctor first before exercising outside.

Myth: You don’t need sunglasses in the winter. Although the sun is less intense in areas that have winter, there are still enough rays to damage your eyes.

“It was imperative to always be wearing tinted goggles or sunglasses,” said McCallum, “as you would quickly develop snow-blindness.”

Myth: Cold weather makes you SAD. Although many people experience Seasonal Affective Disorder (SAD) in the winter, it’s more due to the lack of sunlight than the cold.

“The danger of cold was always present and the most serious threat to our safety,” said McCallum. “However, the dark, the isolation, and the confinement were much more of an everyday challenge.”

This was made worse by the sun being absent all day long for six months in the winter.

Some people, though, actually like the cold.

“Many of us enjoy the terrible and cold weather we see, so that helps keep moods high,” said Gill. “Isolation can get to you the most rather than the cold because once we get to work, we are here for a week at a time.”

For McCallum and the many scientists living together at “one of the most pristine places on Earth,” the South Pole contains extraordinary beauty that makes the cold, dark days worthwhile.

“One theme that repeatedly arises in our book is the comfort I took from the extreme weather — the cold, the whipping wind,” said McCallum. “It was something physical I could lean into and an emotional parallel to our challenging living conditions.”