Chances are you may have a weak immune system. Of course, there are diseases like diabetes, cancer, and AIDS, that will weaken your immune system that are generally out of your control. But for the average person that does not have one of these conditions, how we treat our bodies will indirectly affect the ability of our immune system to fight off diseases and illness.

Naturally, we are all born with different levels of immune systems – some stronger than others. But our daily environment also plays a role in how effective our immune system can be.

Weaker immune systems make us more vulnerable to any illness that affects humans. Repeated infections, inflammation, slow wound healing, and fatigue can all be caused by a weak immune system. If your body is not prepared to fight off invaders, you are going to get sick more often than the average person.

Bad Dietary and Health Habits

There are many things that can depress your immune system. Any one of the factors below can result in an immune system that does not work as well as it should, while a combination of these bad habits means you’re doing a lot of damage to your immune system’s ability to fight off illness.

Too Much Sugar – The average American consumes a lot of sugar – much more than our Paleolithic ancestors, and much more than our foreign counterparts. On average, Americans consume an amazing 100 pounds of sugar per year. We eat this much sugar because of our love of soda drinks, sweets, and processed foods. In the 19th century, where cardiovascular diseases and cancer were not nearly as common, sugar intake was only about 5 pounds per year.

So how does all of this sugar harm our immune system? Studies show that a bad sugar habit can cause mood swings, personality changes, enhance nervous disorders, cause diabetes (of course), speed up the rate of heart disease, and so on and so forth.

Sugar is devoid of any minerals, vitamins, and fiber, so when we ingest sugar our body has to use its own stores to digest it. When your body runs out of its own stores, cholesterol and fatty acid metabolization is slowed. Basically, sugar brings your immune system to a halt.

If you want a more technical answer on why sugar is so bad for our health, this is a great article on the harmful effects of sugar.

Obesity – We all know obesity leads to all types of health problems. This ties into the “too much sugar” issue as well. Once you are considered obese your immune system will suffer.

It is known that obesity has an affect on the immune system, but researchers are still trying to figure out the exact reasons.

Research performed on laboratory mice has shown that obesity prevents the body from turning on its immune system properly, making it more vulnerable to infection. In fact, obese mice were 50 percent less capable of killing the flu virus, compared to lean mice. The research seems to show that the same is true in humans. – Source

Early research shows that, in mice, the T-cells and macrophages (which make up the immune system cells), are not correct in obese mice. The amount of healthy white blood cells (macrophages being white blood cells) are much lower in obese mice as well.

Excessive Alcohol – Most people enjoy a drink once in a while, but if you are drinking a bit too much, it will harm your immune system’s ability to fight off illness. For one, alcohol does not provide any nutrients, which causes a nutrient deficiency (just like sugar). This means that your body has fewer nutrients to nourish the cells that make up your immune system. In addition, and once again just like sugar, excessive alcohol reduces the ability of white blood cells to kill germs.

Smoking – There aren’t many health benefits to smoking. Aside from the high of a nicotine buzz, it is pretty much common sense that smoking harms the body and has no real benefits. When it comes to the immune system, smoking causes more risk for influenza and pneumonia. Smokers also take more time to recover from an illness because it represses the ability of the immune system to function properly.

We Can Improve Our Immune System

The above causes of a weak immune system are all within our control. We have the power to help our immune system function better. If you are always getting sick, you now know why if you are guilty of one of the above causes.

Your immune system is made up of special cells, proteins, tissues, and organs throughout your body. The immune system is not one specific part, but rather, a combination of things within your body to provide a “shield” against incoming bacteria, viruses, and diseases. And when that shield is broken, it is up to the immune system to eliminate the problem.

All plants and animals have an immune system, not just humans. Your body fights off infections and diseases the same way a tree or dog would.

The Immune System is Always Waging War

An easy way to think of the immune system is as our body’s miniature army. We are always at war with the germs around us. The things we touch, the food we eat, and the air we breathe are filled with germs we cannot see – but know that they are there.

Our immune system army keeps these germs at bay, all day and all night. Obviously, our immune system does not go undefeated. When a germ does penetrate the body, it is the job of our immune system army to seek and destroy it before it becomes a problem. The real battle begins when the germ has turned itself into an illness. This is when the immune system wages war and works overtime to get rid of any sickness you may have.

When we are born, we start with a very immature immune system. Babies are given vaccinations (vaccines are a barely-living, or dead strain of a bacteria or virus) to help strengthen their immune system (they build tolerance to the real versions of these diseases) As the years go by, our bodies develop a tolerance for each “sickness” we recover from. For example, we usually catch chicken pox only once in our lives because after the first time we have developed an immunity to it.

Your Immune System has Three Basic Functions

• Prevent bacteria and viruses (germs) from getting into the body
• Should a germ enter the body, it is the immune systems job to find and eliminate the germ before it has a chance to cause a problem.
• Should the germ develop into a problem (infection, flu, etc), it is the job of the immune system to eliminate it.

Your Immune System in Action

You cannot exactly see your immune system, but you can see it working many times throughout your life.

• Healing Wounds – When you cut or puncture your skin, your immune system goes straight to work. An opening in your skin is an invite for bacteria and viruses to get into your body and cause a lot of damage. The immune system tries its best to fight off these invaders while your skin repairs itself.

  Sometimes, a wound can become infected if the immune system missed something. Pus and inflammation around a wound happen as the immune system works overtime to try and fight off the spread of an infection.

• Surviving a Cold or Flu – Colds are caused by bacteria and strains of the flu are causes by viruses (generally). We catch colds and flu from other people when germs are spread, but most of the time our immune system does its job and we do not get sick.

  But, every once in a while these germs get past our immune system and we do get sick. Your immune system is the reason your body survives a cold or flu. Without it, we’d have very short life spans. People with stronger immune systems tend to get sick less often, and are able to recover from illness faster.

• Mosquito bites – When you see the inflammation and suffer the itching of a mosquito bite, this is your immune system at work. Mosquitoes are carriers of disease, so your body has to fight off the germs that the mosquito passed onto you when it sucked out some blood.

Preventing Diseases caused by Germs

When a germ (the generic term for harmful virus and bacteria) finds a host (i.e, enters the body), it reproduces and spreads like wildfire. Germs have only one goal in mind, and that is to spread as quickly as possible. A single bacterium can turn itself into 2 separate bacteria in about a half-hour. Overnight, one piece of bacteria can develop into millions – which is why it does not take much to catch a cold from somebody else. Viruses work differently, but can spread just as quickly.

Infections and illnesses from germs cause things like colds, flu (influenza), mumps, measles, malaria, AIDS, and much more.

The Immune System is not Perfect

Sometimes, the immune system attacks foreign invaders that we actually want inside our body. For example, the immune system attacks “foreign” organs during an organ transplant. This is why organ transplants are much more difficult than they should be. The operation is usually easy. It is the days after a transplant that are the hard part.

Allergies are another error caused by the immune system. Some people react to fur, food, or pollens because the immune system overreacts to stimuli that others do not react to.

Obviously, the immune system is not perfect. If it were, we would never get sick. Or if we had to get sick, no one would ever die from a disease or illness.

Some people have very good immune systems, and do not get sick that often. When they do, they can recover quickly. Others have weaker immune systems, and these people suffer infections and sickness more often than average.

Improving the Immune System

There are certain things everybody can do to improve their immune system, whether it is weak or strong already. This is what we will discuss in the next few articles about boosting the immune system.

Further Reading

If you want to learn about the technical aspects of the immune system, check out these two articles.

• Basics of the Immune System from Kidshealth.org
• How the Immune System Works from HowStuffWorks.com