Leave it to the Mythbusters to prove a point. This time, the point to be proved was that alcohol and cold weather do not go together well. The myth was about a St. Bernard dog carrying a cask of brandy to rescue stranded mountaineers in the deep snows of the Alps. The questions was whether or not that would be a valid rescue tactic.
To demonstrate the effect of drinking alcohol in a cold environment, Adam and Jaime (the Mythbusters) were placed in a huge freezer, and heat sensing devices were used to measure their body surface temperature at hands and face as they sat there and chilled. Both men also swallowed encapsulated thermometers that sent internal core temperature information to digital readouts. So it was all very scientific.
After cooling their heels in the icebox for a while, their skin temperature had dropped quite a bit and they were starting to feel the beginning stages of frostbite. But even at that point, their internal temperature was holding pretty steady.
That's when they decided to see if drinking some brandy, delivered to them in the most authentic manner by a St. Bernard dog, would make them feel warmer. So in came the dog and down the hatch went the brandy. Adam and Jamie both said they felt warmer as the alcohol went down the pipe into their stomach. And by using the temperature sensing devices they were able to verify that their skin temperature was actually warming by several degrees. Thermal imaging equipment graphically showed how much warmer their skin was after imbibing.
But, the internal thermometer told another story. Their core temperature was actually dropping like a rock. That is exactly the wrong thing to have happen if you intend to survive in a cold environment.
There's a physiological reason for all this. Alcohol acts as a vasodilator to open the blood vessels and allow a greater flow of blood from the core of the body to the surface and extremities. That's why the skin temperature appeared warmer on the thermal imaging display, and why Adam and Jamie felt warmer after drinking the brandy.
The problem with that is the extremities are cold, so when the new warm blood arrives it becomes instantly chilled, and then it returns to the core of the body, carrying the cold with it, thereby lowering the body core temperature.
Of course, that was only part of the problem. The other part was that they guys quickly became drunk and lost their ability to make good decisions. It was funny to watch on TV, as the guys started babbling about stupid things, but in a real outdoor survival situation, it would be anything but funny. In a survival situation, whether urban or wilderness, keeping a clear head and being able to make proper decisions is absolutely imperative. You've heard me say it before, 90% of survival is in your head, and this was a good demonstration of what that means.
Final analysis: Do not drink alcohol to try to stay warm. Use it as a fuel to get a fire started. In the end the Mythbusters concluded that they would have been better off snuggling with the warm and furry St. Bernard than drinking the brandy. Very true.