In the United States, temperatures have reached unprecedented and record levels this week, with some cities being considered colder than parts of Antarctica.

At least nine dead in the Midwest have been linked to the extreme weather, showing just how "once in a generation"The polar vortex could be." While you keep an eye on the weather, here are some simple tips for staying safe and protecting your health during this time.

Choose the right type of clothing

When the temperature drops, wearing several layers can help preserve your heart rather than wearing a thick coat. Also make sure the layers are loose because tight clothing can reduce blood circulation as Sharon Brangman, M.D., Upstate University Hospital, New York.

As for the material, Consumer reports Lists of wool or synthetic such as polyester, polyethylene, microfiber and polypropylene as good options to consider. Of course, you should wear insulating shoes slip resistant if you can walk on icy and slippery surfaces.

Face possible frostbite

Frostbite occurs when skin and other tissues freeze due to low temperatures. It usually starts with a feeling of numbness before the skin turns white or blue. If you think that you may develop frostbite, it is important to keep the area covered.

"Do not rub your hands – if you suffer from frostbite or frostbite, friction causes tissue damage," said Dr. Randall Wexler, a professor at Ohio State University. ABC News. Although frostnip can be treated at home, you may need to see a doctor for superficial or deep frostbites.

Stay away from cigarettes and alcohol

Smokers are at higher risk of frostbite because their blood vessels do not expand fast enough to heat different parts of the body. Researchers at Yale University have also to suggest Nicotine can slow down the body's normal cold reaction.

Going to alcohol to protect yourself from the cold is not a good idea either. Although you can feel warm after drinking, alcohol lower your core temperature and affects healthy reflexes such as the ability to shiver.

Avoid too much physical activity

You may have read articles on the increase in the number of heart attacks during the holiday season. Although there are a number of factors, strenuous activities, such as shoveling snow, can be a source of sudden stress and put a lot of pressure on the heart in cold weather.

Due to the dryness of the cold air, you can dehydrate more easily during your physical activities. Drink enough fluids and limit your time outdoors. People with diabetes, respiratory problems, heart failure, etc. should talk to their doctor about any extra precautions they may take.