How many times have you heard your mum tell you: "Wear a jacket or you'll catch a cold!" or "Don't go outside with wet hair"? I know for sure that if I received a euro for every time my mum said one of these statements to me, I would be a very rich woman by now.

But was she right? Or was it just an old wive's tale? So far, researchers who are studying this issue have found that ordinary exposure to moderate cold doesn't increase your susceptibility to infection. But then why do colds and illnesses reach their peak during the winter months?

The majority of health experts seem to agree that people spend more time indoors in closer contact with other people who can pass on germs and microbes. The influenza virus is more prevalent during winter, so if we are in closer contact with each other, we are, in turn, more susceptible to catching this virus.

How is temperature linked to the immune system?

Scientists are still studying whether there is an actual link between the cold and our ability to fight off illness. Some studies have shown that our bodies' ability to fight off disease is lower in colder temperatures as our immune response may be slower.

However, the majority of studies show that there is no need to worry about moderate cold exposure — it has no detrimental effect on the human immune system. Should you bundle up when it's cold outside? The answer is "yes" if you're uncomfortable, or if you're going to be outdoors for an extended period of time. 

So what's the bottom line? Feeling cold does not make you sick. Bacteria and viruses will cause illnesses. Cold weather and other factors like stress and a poor diet may only weaken your ability to fight off illness.

Learn more by exploring the correlation between stress and the immune system, the foods that boost your immune system and how to strengthen your child's immune system.