Staying healthy and not getting sick is an everyday mantra to most of us. But protecting yourself from the common cold or the flu isn’t easy. According to a former director of the Common Cold Centre at Cardiff University, Professor Ronald Eccles, as adults we’re more likely to suffer through having a cold or the flu at least two to three times a year. Your kids, on the other hand, are more likely to get it at least eight times in a year. But, how much do we really know about what causes these symptoms?

real cause of cold and flu
Ugh…Remember those endless tissues with disgusting green blobs…

Sneezing, fatigue, body aches, fever – most of us have experienced these unpleasant symptoms without understanding why and how these symptoms happen. Believe it or not, it’s our body protecting us. When a cold or flu virus enters our body, it starts destroying healthy cells one by one.

This is just the tip of the iceberg since the cell destruction isn’t what makes us sick. It’s actually the inflammation that’s triggered by the chemical response of our immune system! Yes – our own immune system is what causes that yucky nasal mucus, burning fever, horrible aches, and sometimes, constant sneezing.

Basically, all of the cold and flu symptoms you feel are from the inflammation process to get your immune cells – like the T cells and other white blood cells  – to where they need to be.

Thanks white blood cells!

We should actually be really thankful to our immune system for providing us with proper defense mechanisms for fighting off colds and flus. Why? Because it’s more coordinated than us is some ways! Three chemical messenger molecules – cytokines, bradykinin and prostaglandins – do all the coordination work in defending our body from the virus.

It all starts out with the cytokines. These are the first respondenders to the situation by detecting the virus and then calling other white blood cells to the area of infection. They’re like the 911 operators who receive the message first and then help you by calling the police to your house. Cytokines signal other cells to release other chemical messenger molecules, so they can work together to fix or heal the blood vessels.

Blocked nose, sore throat, fevers, the whole catastrophe…

You wake up in the morning and that cold is really hitting you full blast. You may experience a splitting headache or worse a painful throat. Now, let’s get down and dirty to find out why our immune system makes us feel like we’re never going to see the light of day again.

Have you ever woken up in the morning with your throat more painful than when your cold or flu starts out? That’s actually from the bradykinin and prostaglandin molecules that act on the nerves that sense pain in the throat. They are also responsible for your sneezing since they signal the sensory nerves in the nasal area to sneeze.

sneezing
Annoying sneezes thanks to bradykinin and prostaglandins

Most of us experience coughing with the flu or cold. It is usually triggered by the sensory nerves in the airway. Coughing is believed, by some scientists, to mean that the inflammation has spread past the nose and the throat. But this can’t really be pinpointed to anything certain as there are a lot of causes.

The bradykinin and prostaglandin molecules are also responsible for your blocked nasal passages. They cause the blood vessels in your nose to swell and that can leave you literally gasping for air.

Enough about the bradykinin and prostaglandin. Let’s head back to where it all started – with the cytokines. By interacting with the nerve endings of your hypothalamus – the part of the brain responsible for internal temperature control – the cytokines cause fevers and chills when you have the cold or flu. They’re also responsible for the headaches you experience. But, scientists haven’t found out the exact mechanics of how cytokines induce headaches.

Last, but not least, what about that disgusting, green ooze that comes out of our throats and noses. Yes – we know it’s mucus, but it’s more than that. Although there is mucus present, the green stuff is actually a protein called myeloperoxidase – also present in some white blood cells. In the beginning of our cold or flu infection, the color of the mucus is clear or white since the number of white blood cells, sacrificing themselves for your health, are still low. But as our body continues to produce more of these kamikaze white blood cells to fight off the cold or flu, the amount of myeloperoxidase in their collective little dead bodies, changes the mucus colour to yellow or even green!

So now you know more about what really causes those cold or flu symptoms. Next time you feel like ‘death warmed up’, just think of all your little white cell buddies who really are giving up their life… just so you can get back to work!