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I read a recent article on ABC News entitled Cold Weather Myths: What You Need to Know During a Snowstorm.

In this article, they claim that:

Experts say despite the warm feeling a shot of whiskey can bring, alcohol is actually more harmful than helpful in cold temperatures.

Is this true? This is counter to everything I've heard on the subject my whole life, from various sources including outdoorsmen I respect and documentaries.

Are there any benefits to sipping a little alcohol out in the cold? What harm is there to outweigh these benefits?

DCShannon
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2 Answers2

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The main harm from ingestion of alcohol in cold weather is the risk of hypothermia. Alcohol is known to affect body temperature during cold weather as well as hot weather.

  1. Drinking alcohol may decrease one's core body temperature regardless of the outside temperature and might increase hypothermia risk.

Alcohol ingestion increases the risk of acquiring or aggravating hypothermia by causing cutaneous vasodilation (which prevents vasoconstriction), impairment of the shivering mechanism, hypothalamic dysfunction, and a decrease in awareness of environmental conditions. In rural areas, over 90% of hypothermic deaths are associated with elevated blood alcohol levels.

  1. Drinking alcohol in cold weather might reduce the body’s ability and tendency to shiver resulting from alcohol-induced hypoglycemia which again contributes to hypothermia.

Furthermore, the primary mechanism by which alcohol ingestion exacerbates the fall in body core temperature during cold exposure appears to be via an impairment of shivering thermogenesis resulting from alcohol-induced hypoglycemia, rather than by increasing heat dissipation via vasodilation as commonly believed.

There are case studies where alcohol abuse is suspected of contributing to hypothermia by weakening physiologic responses to the cold weather.

Substance and alcohol abuse can contribute to hypothermia by blunting physiologic responses to cold and can lead to prolonged exposure caused by impaired judgment.

  1. Drinking alcohol to help one feel warmer is debunked as a myth referring to Mythbusters.
pericles316
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    Your Mythbusters link says *"one alcoholic drink could make you feel warmer, but it actually lowers your core body temperature"* and *"A nip or two actually causes your blood vessels to dilate, moving warm blood closer to the surface of your skin, making you feel warmer temporarily"* which suggests that ***feeling*** warmer may indeed happen, even if it does not actually warm you. Your other points are much the same: drinking alcohol in the cold may not warm you, but you may feel less cold (indeed feel less anything in general). – Henry Jan 22 '16 at 14:54
  • So it makes you feel less cold and makes you shiver less (which could be a benefit, depending on what you're doing) but increases risk of hypothermia. Got it. – DCShannon Jan 22 '16 at 20:32
  • Drinking alcohol while you are still in a cold environment is bad because you will lose heat faster. But if you have made it into a warm environment escaping a cold one, is it still bad? – matt_black Jan 28 '16 at 11:07
  • Referring to Equinox, "Alcohol and extreme heat have a lot in common in terms of effects on the body, including: dehydration, dizziness, headaches, changes to breathing, changes to heart rate and blood pressure, nausea, vomiting or cramps." – pericles316 Jan 28 '16 at 11:15
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Alcohol expands the blood vessels, bringing the warmth into skin from inside. This creates the feeling of warmth and may protect the skin. However the heat is lost more quickly due heating the skin that is also in contact with the cold surrounding air.

Alcohol also reduces general blood flow through hand and forearm. So bigger parts of the body may actually cool faster.

Hence if there is a danger of the body (or the body part) temperature dropping below acceptable, alcohol increases this danger.

The detailed scientific study on these effects can be found in J D Fewings, M J Hanna, J A Walsh, and R F Whelan (1966) Br J Pharmacol Chemother. The effects of ethyl alcohol on the blood vessels of the hand and forearm in man. May; 27(1): 93–106, PMCID: PMC1510798. It is freely accessible here.

h22
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  • Comment deprecated – h22 Jan 27 '16 at 12:50
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    This does not add much to the answer from 21 January –  Jan 27 '16 at 13:18
  • Adds "alcohol also reduces general blood flow through hand and forearm", also explains the mechanisms as found in the reference to the true scientific work. – h22 Jan 27 '16 at 14:02