There's no such thing as blood thinning in warmer climates, did you know that?

When the temperatures drop, the old wives' tales come out -- time-honored "facts" about surviving winter weather that we've all come to know. But how many of them are actually true?

Let's break down some of our favorite cold weather myths.

MYTH: Floridians have thinner blood

It's a common saying among Florida transplants after they've lived in the Sunshine State for a while that their blood is now thinner and that's why we're all in jackets and sweaters in 60 degree weather.

But your blood doesn't "thin," per se.

Doctors say what is happening is that the capillaries in the skin dialate in warm weather, so it takes longer for them to constrict in cold weather. You feel colder longer, but it's a tolerance thing. Your blood is actually not "thinner."

Blood thinning is an actual medical condition and refers to low red blood cells in the blood. People who are anemic tend to have a low red blood cell count. But not everyone in warmer climates is anemic.

MYTH: Cold weather makes you sick

“That’s false," said Dr. Timothy Hendrix with CentraCare. "Colds are caused by viruses that are spread from person to person. Being exposed to cold weather can increase your chances of getting sick because it reduces your immune response, so it puts a stress on your system. Viruses like cold, dry weather so they're very easily transmitted, but just getting cold will not make you sick."

MYTH: You could get sick from having wet hair

“You’re going to get chilled," Dr. Hendrix said, "and it’s going to get colder and you are going to lower your body temperature because of that but it’s not going to make you sick.”

MYTH: If your feet are cold, the rest of your body is cold too

“That’s untrue," said Dr. Hendrix. "When your feet are cold it’s because your veins are constricted. Your blood flow is limited to your extremities during the cold weather because your body is trying to conserve that body heat to the important organs like your heart. So that just indicates that it is cold outside and your body is trying to conserve that warmth.” 

MYTH: You have to warm up the car before you drive by letting it idle

If this is something that used to be true, it's not anymore. In fact, getting the car on the road is probably better for the car.

The Environmental Protection Agency and the U.S. Dept. of Energy say driving your car will warm it up faster than idling it, both the inside heat and under the hood. Maybe 30 seconds, tops.

Now that doesn't mean going from 0 to 60 in under 30 seconds, but easing onto the road can actually be better for the life of your engine. The only reason to "warm up" the car in the morning is if you have frost on the windows, but that has more to do with not having enough visibility to drive.

MYTH: Drinking warm drinks will keep you warm

Hot chocolate. It's the soothing drink that conjures up images of bundling up in pajamas with a blanket on the couch, maybe in front of the fire. Or is that just a Swiss Miss commercial...?

While holding that hot mug in your hand may give you the warm fuzzies, it actually doesn't give you any lingering warmth.

"You can increase your body temperature by drinking some warm liquids, but not enough to combat the heat loss through skin in the cold weather,” Dr. Hendrix said.

In fact, you may actually lose body heat.

When you drink something hot, nerve receptors in your tongue tell your body to start sweating because it's about to get hot. You sweat, that's a body's natural cooling system.  Neuoscientists say you should save the hot drink for a hot day and for a natural cooldown.

MYTH: Drinking alcohol makes you warmer

While we're at it, what about that other drink that gives you a warm glow? Actually, alcohol gives you the exact opposite.

“You are dropping your body temperature as you drink which is not good in the cold weather,” Dr. Hendrix said.

MYTH: Cotton is a good insulator

“Cotton will retain moisture," said Dr. Hendrix. "So that’s why wool is a better insulator because it allows that cushion of air next to your skin that will keep you warm and keep all that moisture evaporated.”

MYTH: You don't need sunscreen in winter

For Floridians this should be a given, but in case people don't know -- the sun shines when it's cold, it shines when it's hot. Heat has nothing to do with UV rays, which come from the sun all year long. So no matter what, if you're going to be out all day, you should probably wear some sunscreen.

MYTH: You lose the most heat through your head

People who go out in cold weather without a hat on will lose heat through their head, right? If they are bundled up every where else, they might. But you won't lose the most through your head. You won't lose any more heat from your head than you would from any other part of your body. Still, if you're bundling up, you might want to leave your hat on.

MYTH: Cold weather causes people to gain weight

"Well I do!" Dr. Hendrix said. "It's called the holidays."