This week"s polar vortex has carried bitter cold — also Arctic-like temperatures — to parts of the upper Midwest and also Eastern U.S., and also this frigid air may have actually you feeling choose you can "freeze come death."

Indeed, when temperatures dip this low, frostbite and also hypothermia space real wellness concerns. Weather officials have warned the dangerous and also even life-threatening wind chills v Thursday (Jan. 31). <7 Crazy things That happen Only when It"s really Cold>

However, fatality from the cold can happen also if the body isn"t accurate frozen.

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main point temperature drop

A person"s main point body temperature usually hovers about 98.6 degrees Fahrenheit (37 levels Celsius). Hypothermia occurs as soon as core human body temperature dips to about 95 F (35 C) or lower. Surprisingly, human being can suffer hypothermia in relatively cool, however not freezing, air temperature — roughly 30 come 50 F (minus 1 come 10 C) — particularly if they space wet, such as from rain, sweat or submersion in cold water, according to the national Weather Service. The human body loses heat about 25 times quicker in water than in air, Michael Sawka, chef of the heat & mountain Medicine division at the U.S. Military Research academy of environmental Medicine (USARIEM), said Live scientific research in a 2010 interview.

But hypothermia in ~ these fairly cool temperature is unusual.

Temperatures that are subzero, however, room "a whole different animal," stated Dr. Robert Glatter, an emergency doctor at Lenox Hill Hospital in brand-new York City.

At minus 30 F (minus 34 C), one otherwise healthy and balanced person that isn"t appropriately dressed because that the cold could experience hypothermia in as little as 10 minutes, Glatter said. In ~ minus 40 come minus 50 F (minus 40 to minus 45 C), hypothermia can set in in simply 5 to 7 minutes, the said.

A fall in human body temperature prevents an important organs indigenous working appropriately — consisting of the mind and heart, according to the mayo Clinic.

Improper functioning of the heart outcomes in reduced blood flow to plenty of organs, putting the human body in a state that shock and increasing the risk of conditions like liver failure and also kidney failure, Glatter said Live Science. The very young and the an extremely old room at higher risk because that hypothermia since they typically have weaker love muscles, he said. In addition, older people are an ext likely come take medications such as beta blockers that deserve to slow love rate, which further increases their risk of emerging hypothermia in the cold.

Symptoms of soft hypothermia, such as shivering, weakness and confusion, set in once core human body temperature reaches about 95 F. After that, "as you begin dropping , poor things happen," Sawka said.

At 91 F (33 C), you can experience amnesia.At 82 F (28 C) you can lose consciousness.Below 70 F (21 C), friend are said to have actually profound hypothermia and death deserve to occur, Sawka said.

The document for the lowest human body temperature at which one adult has actually been well-known to survive is 56.7 F (13.7 C), which occurred after the human being was submerged in cold, icy water for rather some time, according to man Castellani, the the USARIEM, who also spoke v Live scientific research in 2010.

Left untreated, hypothermia can lead to complete failure of the heart, and also eventually death, according to the mei Clinic.

integrated cold protection

Yet people"s bodies space pretty hardy in the cold, together we have actually two built-in mechanisms to safeguard us from frigid conditions.

As soon as that bitter air hits her face, her body will try to insulate chin by moving blood far from the skin and also outer extremities, such together fingers and also toes, and also toward that core. This process is dubbed vasoconstriction, and it helps limit the quantity of warmth you shed to the environment, Castellani said.

The 2nd response from your body is shivering, which produces heat and also helps raise human body temperature.

frostbite danger

Although extreme problems are frequently needed come induce hypothermia in a healthy person, frostbite is much more common in less severe weather. "It take away a lot come drop the main point body temperature down, yet it doesn"t take it as lot to drive the peripheral temperature down," Castellani said.

Your fingers and toes are more prone to frostbite, due to the fact that those areas will have lessened blood circulation in cold temperatures, as your human body tries to keep its main point warm. Even though your feet room usually protected by shoes, toes temperatures deserve to get an extremely low, and also if friend sweat, the wetness will attract even an ext heat the end of the area. Since frostbite is carried on by freezing, girlfriend can"t acquire frostbite if the wait temperature is above 32 F (0 C).

How long it takes you to construct frostbite will rely on the conditions. For example, if it"s 0 F (minus 18 C) with a wind chilled of minus 19 F (minus 28 C), you could be frostbitten in 30 minutes; but if it"s minus 15 F (minus 26 C) with a wind cool of minus 55 (minus 48 C), you can get frosting in as couple of as 5 minutes, according to the nationwide Weather Service. Regardless of these risks, "human beings can go the end in an extremely extreme cold environments and do really well," Castellani said. People climb mountains, trek in the Arctic and also swim the English Channel, i m sorry has really low water temperatures.

Still, you need to be correctly dressed to weather the cold conditions. Glatter recommended that people wear at least three great — a wicking layer that wicks moisture far from the skin, one insulating layer and a protective external layer to protect against the wind and also other elements. In addition, Glatter encourage that people wear thick, insulated boots, since the feet and toes room at high risker threat for frostbite.

The CDC likewise recommends that world wear a hat, scarf or confront mask the covers the face and mouth, a water-resistant coat, mittens or gloves, and also water-resistant boots.

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Editor"s note: A version of this post was published on Jan. 7, 2010. It to be updated with new information and an interview through Dr. Glatter ~ above Jan. 30, 2019.