Cold and flu season has officially arrived and it can be difficult to keep yourself from succumbing to one or the other, or both if you’re unlucky. It isn’t just a nasty cold or flu virus that can have you feeling less than great during the winter months, you may also experience a worsening of other health conditions such as arthritis or diabetes. Research from Cambridge University helps to bring some clarity when it comes to why you actually get sick in cold weather.

What Causes Cold Weather Illness
It’s a fact that illness rates go up during cold weather and there has been little indication as to what is actually causing this. A study conducted by John Todd, professor of Medical Genetics at Cambridge University, concludes that your genes are responsible for the increase in illness and discomfort you experience during the winter. Why does this happen? The theory is that your genes actually change their behavior in response to seasonal changes. This amazing bit of science was discovered by chance by one of Professor Todd’s Ph.D. students. The student noted that during winter, immunity genes were more active in white blood cells than they were at other times of the year. White blood cells are the cells in your body that are responsible for fighting off infection and illness.

Scientific Study Provides Support
Once the discovery had been made, Professor Todd launched a research study that included over 16,000 worldwide. The research team, lead by Todd, carefully analyzed blood and tissue samples from participants coming from a large variety of climates and environments. Your body contains around 24,000 genes and the research conducted by Todd and his team analyzed 22,000 human genes, making it a comprehensive study.

What they found was that nearly one-quarter of genes in the human body show signs of altered behavior during seasonal change. The weather in Britain changes significantly with the seasons, much like it does here. Todd found that during the winter months, immune system genes ramped up their activity during the winter months. However, samples from Iceland, where it is cold the majority of the time and there are few seasonal changes, showed that genes were more active prior to the rainy season in Iceland.

Why do Genes Change Behavior and Why Does More Immune Activity Make you Sick?
While the study indicated clearly that there are many genes that alter their behavior according to season changes, the reason why is still unclear. The researchers who conducted the study believe that genes receive natural clues from their environment, such as temperature or sunlight, and then respond accordingly.

If your immunity genes in white blood cells are more active during cold, winter months, then why do you still get sick? Shouldn’t more activity equal more protection? Not entirely. Professor Todd explains that the spike in activity can cause your cells to malfunction and attack your body instead of just foreign invaders. Your immunity genes control white blood cells, which triggers inflammation. Chronic inflammation is a major component of serious diseases such as heart disease, arthritis and type 1 diabetes.

What Does All of This Mean?
The research all boils down to one fact: if you know more about what’s wrong, you can treat the condition more effectively. Drugs that target inflammation may be more effective when used during the winter months to treat serious conditions like arthritis. Additionally, Professor Todd suggests that perhaps instead of getting vaccinated immediately when fall starts, it may be more beneficial to be vaccinated later in the winter when your body is already primed for immune action.

Staying healthy during winter weather can be a challenge and some places, like at work or school, you can’t fully control your exposure to bacteria and viruses. Understanding what happens to cause illness in cold weather is a promising step in discovering how to more effectively prevent and fight these illnesses as well. Remember to wash your hands thoroughly and often and to stay home if you are sick to avoid spreading germs. Even though your genes alter their behavior, prevention of disease by hand washing and vaccination is still important because these practices can significantly lessen the severity of your illness.