According to the old wives' tale, if you go outside on chilly days without a jacket or with a wet head, you'll catch a cold. Like many such tales, the statement isn't completely accurate, but it does have a grain of truth. The cold air won't give your baby a cold, but it can make her more susceptible to the virus that causes colds.
Colds are caused by viruses. With more than 100 types of virus that can lead to a cold, it's tough to avoid a cold even with the best of immune systems, according to KidsHealth.org. Your baby's immune system is still developing -- it is weakest from birth to 6 weeks old. After his immune system kicks in, the immune system still has to grow and strengthen, just like your baby does. If he comes into contact with a cold virus, he could catch a cold even if he never leaves the warmth of the house.
Temperature and the Virus
Colds are more common during the chilly months, and there's a scientific reason for that, according to a 2008 story on the Science Daily website. Cold and flu viruses typically are covered by a thick protective coating. In cool temperatures, this coating is rubbery, providing excellent protection and allowing the virus to live on surfaces longer. When the temperatures are warmer, the coating melts slightly so that it's more of a liquid. The liquid coating doesn't do as good at protecting the virus cell, so the cell doesn't live as long when exposed to the air, giving it less chance of infecting a person.
Temperature and Your Baby
Cold air tends to be less humid that hot, summer air. When you take your baby out in the cold, even bundled up, he's breathing in that chilly, dry air. This causes the blood vessels inside his nose to constrict, which makes his nose drier inside and less able to flush out cold virus cells that attempt to attach to the lining of the nose, according to the WebMD website. Temperatures just make it easier for the virus to successfully infect him.
Keeping Him Healthy
You can't prevent your baby from catching a cold eventually, but you can minimize the risk, even in cold weather. KidsHealth.org recommends you wash your hands often, and ask anyone who cares for him or holds him to do so with clean hands. Wash his favorite toys daily because they're likely to go straight into his mouth, germs and all. Sanitize his bottles, nipples and pacifiers daily as well. After you take him out into the cold, wash his hands thoroughly to remove any germs he might have picked up during the outing.