Get the straight story on the role of bacteria, viruses and your immune system.

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When it comes to your immune health, there are tons of myths. As your body's bodyguard, your immune system needs to have a wide range of solutions, making it quite complex. Because of its intricacies, it's easy to misunderstand your poor immune system. Here, we dispel a few common myths.

Myth 1: Bacteria is just plain bad.

Bacteria may get a bad rap, but we can't live without them. They help digest food and add nutrients to our food choices before we even eat them. Good bacteria help keep the bad bacteria away. Pharmaceutical companies grow bacteria to help make useful drugs, human growth hormone, and even beer.

But, like breakfast cereal, there are as many bad kinds out there as there are good. Bacteria (which are single-cell organisms) are neither animals nor plants. They're actually prehistoric organisms lacking the architecture of human cells (nuclei, the brain of our cells).

A thousand bacteria could fit into the thickness of a dime. They replicate themselves and this causes infection. Antibiotics designed to kill bacteria can kill pimples or strep throat.

Bacterial infections can also be sexually transmitted. Chlamydia, one of the most common, yields no symptoms in 75 percent of people that have it. If left untreated, chronic inflammation in your body can age your arteries. Wearing down your immune system can cause permanent damage to your organs. For example, uncontrolled strep can result in tonsil abscesses, which contribute to breathing problems, and can lead to kidney and heart damage.

Myth 2: Viruses typically cause the common cold, not bacteria.

The most common virus? The one that causes the run-of-the-mill cold. This is actually made up of several different families of viruses. You may experience upper-respiratory symptoms that are associated with bacterial infection, however, bacteria does not cause most common colds. This is why antibiotics are useless against them. If the illness continues, you may have attracted bacteria secondarily, as a result of the virus weakening you.

A common sign of a secondary bacterial infection? Producing colored, thick mucus or sputum from your nose or throat. The majority of viral cold infections run their course, exiting your body through portholes associated with sneezing, nose blowing and coughing. When you take antibiotics for a viral infection, they can actually have a negative effect.

They kill only the susceptible bacteria, allowing the more dangerous, resistant strains to get stronger. So no need to pester your doctor for antibiotics if you know it's a virus. They may have a placebo effect but won't actually help you. Antibiotics can harm you, unless you have a bacterial infection on top of your viral one.


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