7 Interesting Facts About The Human Immune System
The human body is an absolute marvel of science and biology, with every
limb, bone, tissue and cell having their own important functions. One of
the most important systems in the body has to be the immune system. Our
immunity is what keeps us alive in a world teeming with bacteria and
germs. If you've ever seen the movie "The Boy In The Plastic Bubble"
(1976), you might gain some understanding of what the world can be like
if you have no immune system.
Our knowledge about this particular system has revolutionized medicine,
propelling the creation of most vaccinations, that have drastically
increased the average human life span. To give you a little bit more
insight into this incredible system of warriors and protectors, here are
7 facts you may not have known about your immune system.
1. Laughter can really be the best medicine
Studies have shown the general positive effects that laughter can have
on the body. Laughter (and enjoyment in general) can increase the
production of dopamine, serotonin and other feel-good hormones released
by the brain, which can drastically reduce stress.
According to a study by Dr. Stephen Sinatra, laughter can also boost your immune system by increasing the cytotoxicity (which is basically the ability of one type of cell to foreign cells) of NK cells (natural killer cells). Natural Killer Cells are the type of white blood cells that can actually differentiate between infected or cancerous cells and normal ones.
They can avoid the latter and wipe out only the former in a much more effective way.
2. White blood cells are the 1%
White blood cells, also called Leukocytes, are the knights of the human
body, fighting off harmful bacteria and keeping your body free of
infections and viruses. It is one of the most important components of
the human body. So one would think that the bloodstream is chock-full of
these heroes, but in reality, they only make up 1% of the cells in your
blood.
In this case, though, the 1% is pretty large, with up to 10,000 white
blood cells in every microlitre (one-millionth of a liter) of blood.
That counts for a lot when you consider the fact that there are 5 liters
of blood in the human body. These cells are always on the move in the
bloodstream, hunting down possible invaders, anywhere they might be.
3. Cows revolutionized our immunity
People first began experimenting with inoculation in the 1700's by
introducing milder, but still deadly elements of the smallpox virus
taken from previously inoculated patients, so the immune system could
develop a resistance to the virus. Though this method was quite
effective, it still resulted in many deaths.
It was eventually discovered that dairymaids had developed a stronger
immunity to smallpox than most people when they had been previously
exposed to cowpox, a disease with a lower fatality rate than Variolation
(which is what the method of inoculation for smallpox, also known as
Variola, was called). Using this knowledge and the cowpox virus, Edward
Jenner pioneered a smallpox vaccine in 1796.
4. There is such a thing as too clean
The common belief is that the cleaner our environment is, the safer we
are. But this is a misconception bred and borne by us. In truth, an
extremely clean environment can halt the development of your immune
system.
Your immune system ends up not getting exposed to many of the foreign particles that usually help it develop anti-bodies and become stronger. This can be especially problematic for children, whose immune systems require exposure to develop and grow.
5. Allergies are just the immune system’s mistakes
Everybody makes mistakes and your immune system is no different. Most of
the reactions your body has to substances you're allergic to arise
because the immune system gets confused and mistakenly takes the foreign
substance, be it pollen, peanuts or dust, to be a dangerous foreign
particle.
So it reacts the way it's built to react to anything that it has understood to be harmful and attacks the substance in your body, doing some damage to your body in the process. This causes many of the symptoms we experience, from itchiness to swelling in different areas.
6. Women are more vulnerable to immune system attacks
Autoimmune diseases, like rheumatoid arthritis, basically occur when the
immune system gets all turned up. It becomes extra defensive and is
unable to differentiate harmful foreign bodies from healthy cells and
tissues in the body. So it begins to attack perfectly healthy cells,
which can cause inflammation, severe pain and numerous other serious
health problems. But as it turns out, autoimmune diseases are somewhat
selective.
While less than 10% of the population in the USA suffer from auto-immune diseases, an article published in 2008 in the American Journal of Pathology observed that nearly a whopping 80% of those suffering from autoimmune diseases were women. Women can be especially vulnerable to these diseases during ovulation, pregnancy and immediately after giving birth.
7. Stress, sleep, sunlight and your immune system
Stress is not good for your immune system. Too much stress may result in
your immune system getting suppressed, which directly increases the
likelihood of you catching a virus.
Lack of sleep similarly affects your immune system, reducing the number of natural killer cells in your body, and can even reduce the effects of vaccinations as a result, as observed in a 2012 study. Sunlight can have mixed effects.
Exposure to sunlight can increase the
Vitamin D in your body, as well as the production of serotonin, which
keeps you happy and can help reduce stress. But high levels of exposure
to ultraviolet radiation and sunlight can result in the suppression of
the immune system, and thereby an increased vulnerability to infections
and viruses. As with most things, a little is good for you, a lot can be
bad.