What happens if you get so cold? A deep dive into hypothermia and cold-related risks

According to the Centers for Disease Control and Prevention (CDC), hypothermia is a major risk during cold weather, with over 1,300 people dying from it between 2003 and 2018 in the U.S. alone. So, what happens if you get so cold that your body's core temperature begins to drop dangerously low? {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Quick Summary

Severe cold exposure can lead to hypothermia, a medical emergency where the body loses heat faster than it can generate it, affecting brain function, coordination, and, if untreated, causing organ failure and death. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Key Points

• Hypothermia Stages: The body progresses through mild, moderate, and severe stages of hypothermia as core temperature drops, with symptoms ranging from shivering and confusion to loss of consciousness and cardiac arrest. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

• Core Temperature is Key: A core body temperature below 95°F (35°C) is a medical emergency requiring immediate attention. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

• Beyond Hypothermia: Severe cold can also cause other injuries like frostbite (frozen tissue), trench foot (from cold and wet feet), and chilblains (small capillary damage). {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

• Recognize the Warning Signs: In adults, watch for shivering, confusion, slurred speech, and clumsiness; in infants, look for bright red, cold skin and very low energy. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

• First-Aid Steps: For a person with suspected hypothermia, move them to a warm place, remove wet clothing, warm their core gently, and seek immediate medical help. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

• Avoid Alcohol and Caffeine: These substances interfere with the body's temperature regulation and impair judgment, increasing vulnerability to cold injuries. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body and how to protect yourself this winter}

• Prevention is Vital: Dressing in layers, staying dry, and limiting exposure are the best strategies to prevent cold-related health problems. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

The body's defense against the cold

When exposed to cold, your body initiates defenses to maintain its 98.6°F (37°C) core temperature. Vasoconstriction narrows blood vessels in extremities, preserving core heat but risking frostbite. Shivering, involuntary muscle contractions, generates heat but can exhaust energy reserves. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

The three stages of hypothermia

If defenses fail and core temperature drops, hypothermia progresses through stages.

Mild Hypothermia (95°F to 89.6°F / 35°C to 32°C)

Symptoms include intense shivering, fatigue, confusion, poor judgment, and increased urination. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Moderate Hypothermia (89.6°F to 82.4°F / 32°C to 28°C)

Shivering may stop. Symptoms include slurred speech, decreased mental function, slowed breathing and heart rate, pale or bluish skin (cyanosis), and paradoxical undressing. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Severe Hypothermia (<82.4°F / <28°C)

This critical stage involves loss of consciousness, minimal breathing and pulse, dilated pupils, muscle stiffness, and high cardiac arrest risk. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Other cold-related injuries

Beyond hypothermia, severe cold can cause other issues.

Frostbite

Freezing of skin and tissues, often in extremities.

• Signs: Cold, tingling, numbness, followed by white or grayish-blue, waxy skin.
• Treatment: Gradual warming with body heat or warm water; avoid direct heat.

Trench Foot (Immersion Foot)

Caused by prolonged cold and wet foot exposure.

• Cause: Wet feet lose heat rapidly, restricting circulation.
• Symptoms: Redness, numbness, swelling, blisters. Can lead to tissue death. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Chilblains

Painful, itchy red patches from repeated cold exposure just above freezing.

• Cause: Damage to skin capillaries from cold.
• Symptoms: Redness, itching, inflammation. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Comparison of cold-related conditions

Feature	Hypothermia	Frostbite	Trench Foot	Chilblains
Body Part Affected	Entire body (core temperature)	Extremities (skin and tissues)	Feet (prolonged wetness)	Extremities (skin)
Core Temperature	Below 95°F (35°C)	Unaffected, but can occur with hypothermia	Unaffected, but can occur with hypothermia	Unaffected
Primary Cause	Body loses heat faster than it produces it	Freezing of skin and tissue	Prolonged exposure to cold, wet conditions	Repeated exposure to cold (non-freezing)
Primary Symptoms	Shivering, confusion, clumsiness, lethargy	Numbness, waxy-looking skin, blisters	Tingling, numbness, swelling, blisters	Redness, itching, inflammation
Medical Emergency?	YES	Yes (depending on severity)	Yes (to prevent gangrene)	Rarely (primarily a nuisance)

{Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Immediate action for severe cold exposure

Moderate to severe hypothermia (below 95°F) is a medical emergency.

1. Call for help: Contact emergency services immediately.
2. Move to shelter: Get the person to a warm, dry place or shield them.
3. Remove wet clothing: Carefully remove wet clothes and replace with dry layers.
4. Rewarm gently: Use blankets or body heat on the core. Avoid rubbing or jarring.
5. Monitor and support: Check for breathing/pulse; perform CPR if trained and needed. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Prevention is your best defense

Dress in layers, wear a hat and gloves, and use moisture-wicking fabrics. Avoid alcohol and caffeine. Stay informed on weather and limit exposure. The CDC offers further guidance on preventing cold-related illnesses.(https://www.cdc.gov/winter-weather/prevention/index.html)

Conclusion

Getting dangerously cold triggers a progression from protective responses to life-threatening hypothermia. Recognizing the signs of hypothermia and other cold injuries like frostbite is essential for prevention and response. Taking steps to stay warm and knowing how to react in critical situations can significantly reduce the risks of severe cold exposure. Swift action for any sign of moderate or severe cold injury is key. {Link: American Heart Association https://www.heart.org/en/news/2025/01/03/what-cold-weather-does-to-the-body-and-how-to-protect-yourself-this-winter}

Frequently Asked Questions

At what temperature does hypothermia occur?

Hypothermia officially occurs when the body's core temperature drops below 95°F (35°C). While this is a critical threshold, dangerous symptoms can begin at higher temperatures, particularly if accompanied by wind, wet clothing, or immersion in cold water.

What is paradoxical undressing in hypothermia?

Paradoxical undressing is a symptom of moderate to severe hypothermia where a person becomes confused and disoriented, mistakenly believing they are hot, and begins to remove their clothing. This is a grave sign and indicates a critical drop in core temperature.

Is frostbite a type of hypothermia?

No, frostbite is not a type of hypothermia, though they often occur together. Hypothermia is a dangerous drop in the body's core temperature, while frostbite is an injury caused by the freezing of skin and underlying tissues, primarily in the extremities.

Why do you stop shivering when hypothermia worsens?

Shivering is the body's attempt to generate heat. As hypothermia progresses to the moderate stage, the body's energy reserves are depleted, and its ability to regulate temperature fails, causing the shivering to stop. This cessation of shivering is a critical warning sign that the condition is worsening.

How can you tell if an infant has hypothermia?

In infants, signs of hypothermia include bright red, cold skin, and unusually low energy or decreased feeding. Unlike adults, infants have a larger body surface area relative to their body mass, making them more susceptible to rapid heat loss.

What should you NOT do when treating someone with hypothermia?

You should not rub or massage the person's extremities, as this can force cold blood to the core and trigger cardiac arrest. Additionally, avoid giving alcohol or caffeine, and do not apply direct heat, such as from a heating pad or hot water, which can cause burns.

Who is most vulnerable to cold-related injuries?

Older adults and young children are particularly vulnerable because their bodies have a harder time regulating temperature. People with chronic medical conditions, those who consume alcohol or use drugs, and individuals with inadequate clothing or shelter are also at higher risk.