The importance of a healthy immune system (Part II)

We know that things like stress, overeating, lack of exercise, smoking and other lifestyle factors influence our likelihood of dying from a number of things, including cancers, but why? In many cases, it appears that lifestyle factors influence immune system health first, which leaves us vulnerable to disease causing life forms (like bacteria, parasites, worms), viruses (like herpes, bird flues, SARS) and mycobacteria (like pneumonia, cell wall deficient Lyme, tuberculosis).

The flu pandemic of 1918 offers plenty of good reasons for trying to maintain a healthy immune system. In 1918 and 1919, the world was ravaged by a flu virus. Sometimes called the Spanish flu, the strain is now thought to have emerged in the United States. It was passed around by military personnel before being unleashed on the public. American soldiers carried it with them to Europe during WWI, where it spread like a plague through both axis and allied forces. Before burning itself out in 1919, the virus killed between 20 and 100 million people worldwide -- 700,000 here in the US .

The good news is that not everyone infected with the virus died, just like many people have already survived the dreaded H5N1 strain of the bird flu – about 40% of the nearly 300 people infected worldwide have lived. It's impossible to know why some people make it and some don't, but keeping your immune system prepared can't hurt your odds!

In addition to decreasing the chances of contracting new diseases and dying from many existing ones, maintaining a healthy immune system can also keep old disease-causing-pathogens from flaring up. Cold sores, for instance.

Cold sores don't really have anything to do with cold viruses. They're caused by one of the many herpes viruses, a category that includes chicken pox, shingles, and others. How and why would that virus affect a person when they're sick with a cold? Once we contract herpes viruses, they tend to retreat inside of the nerves connecting our central nervous systems (brains and spinal cords) to the rest of our bodies. This includes the nerves that carry information to and from the face and the brain. Every now and then, for a reason usually associated with stress or an overwhelmed immune system, the herpes virus comes out of the nerves, enters skin cells and then causes them to erupt. If the immune system is busy fighting another pathogen, like a cold virus, disease causing agents like the herpes virus can come out to play and wreak havoc. So, while not caused by a cold virus, having a cold increases the odds that opportunistic viruses, like the one that causes cold sore, will come out of hiding.

Here's another example of how a disease makes a comeback when the immune system is bogged down. Have you ever heard of someone getting the flu and then dying of pneumonia? The flu bug is a virus and pneumonia is a strange form of bacteria called mycobacteria. What's the connection? It appears that the immune system gets bogged down waging war against the flu virus, which leaves us more susceptible to pneumonia.

Having a strong immune system is the best deterrent to an outbreak of cold sores, shingles, genital herpes, and who knows what else. If the immune system isn't on point, either because drugs are suppressing it, it's tied up fighting an existing illness, or because it's just unhealthy, we become more susceptible to foreign invaders and cancer cells.

The impact of HIV on health is easy to understand in this context. The virus essentially disables the immune system, leaving the host susceptible to ailments from intestinal bugs to pneumonia, as well as certain cancers like Kaposi's sarcoma and non-Hodgkin's lymphoma. The HIV virus doesn't directly kill HIV sufferers. Its impact on the immune system, the Acquired Immune Deficiency Syndrome (AIDS) part, does.

Taking care of the immune system is no easy task. Essentially everything your doctor has ever told you about a healthy lifestyle ties into immune system health. Exercising directly boosts levels of key immune cells. Eating healthy foods provides the building blocks for the immune system, as well as endocrine hormones, and helps minimize the impact of day to day burdens, like stress–induced immune suppression, on our overall health and well-being.

Following a physician's advice and making well-informed decisions about supplements, exercise and food choices, can help keep the immune system prepared for battle. Extensive reseach suggests that transfer factors can help keep the immune system functioning at a high level. This is extremley important in a world where air travel can get a virus from Indonesia to North America in a matter of hours and even eating bagged spinach can be deadly at times!