What causes cancer?

Most people want to know what causes cancer so they can avoid getting it. First, it is important to understand how cancer occurs in a person's body. Cancer is the result of cancerous cells taking over a part of your body. Cancerous cells are created in two ways:

• An otherwise healthy parent cell messes something up during the division process, resulting in two abnormal daughter cells (this is purely by chance and cannot be controlled).



• Some outside influence, like air pollution, damages the cell, which in turn divides into two daughter cells that carry the same characteristics as their parent cell (i.e., the daughter cells are also damaged).

• Age. Generally speaking, the older you get, the more likely you are to develop cancer. This is because at the age of 60, your cells have had a lot more opportunities to botch up something in the division process and a lot more exposure to external factors, like the sun, than a person who is 18 years old.



• Chance. Remember when I talked about the parent cell messing something up in the division process? Sometimes what causes cancer in a person is that some of their cells have more of a tendency to botch up the division process than another person’s cells. Unfortunately, this cannot be controlled.



• Immune system. If a person's immune system has been weakened due to AIDS or an organ transplant, that person may be more likely to get cancer. This is not to say that if you have had an organ transplant that you will get cancer - it just means that you have a higher probability of developing cancer compared to someone that hasn't had an organ transplant.
  
  Also, there are some people that are born with rare medical conditions that cause their immune systems to be weak; those people are also at a higher risk of developing cancer. Click here to learn more about the immune system and its effect on your body's ability to fight cancer. (opens a new window)



• Viruses. Viruses like HPV (human papillomavirus) and Hepatitis B can cause a person's cells to change their genetic make-up (in the same way an external factor like air pollution can damage a cell's make up), which can result in the creation of cancerous cells. Again, if you have had a virus that can lead to cancer, don't start hyper-ventilating - these viruses simply put you at a higher risk of developing cancer. If you have had a virus that has a known link to a cancer, then just be extra vigilant about keeping tabs on your health.



• Genetic make up. Some people just "drew the short straw" so to speak with respect to their genes. These people were born with some cells that were already abnormal. The best way to explain this concept is by sharing a conversation I once had with my aunt, a PA (physician's assistant) in South Dakota. We were talking one day about how two people that have very similar genetic make ups and have been subject to the same environmental factors (like a city’s air pollution) can end up with such different medical histories. For example, how did it happen that I got cancer but my sister didn’t? We have the same parents, grew up in the same house, ate the same foods, and had lived in the same city for most of our lives up until the point I was diagnosed with cancer. How did my sister manage to sidestep Hodgkin’s lymphoma?
  
  My aunt talked about “cancer triggers” that exist in each person’s body. Similar to a light switch that is turned on and off in a room, cancer triggers either allow or disallow an external factor, like regular exposure to air pollution, to manipulate otherwise-healthy cells and turn them into cancerous cells. I don’t know what factor or factors triggered my cancer (most people don’t), but my sister obviously doesn’t have the same trigger in her body that I do (thankfully!).
  
  Not everyone has the same cancer triggers – and some people may not have any cancer triggers! This would explain why my grandmother, who has smoked a pack of cigarettes everyday for the last 65 years and has never exercised a day in her life, is still living a happy and cancer-free life at the age of 92. It's just luck of the draw!



• Risky behavior. Do you smoke? Lay out in the sun for hours in the summer without wearing sunscreen? Work in an environment where you're regularly exposed to carcinogens? If so, stop now! These activities can all lead to cancer. There are a lot of things we can't control when it comes to cancer, but this is one of the areas we can each control in our lives. Stop smoking, wear sunscreen, and get a job that doesn't force you to breathe in toxins.



• Diet. This is still a very grey area to scientists. It seems like every time you turn on the TV or read the newspaper, there is a report about some food or additive and its links to cancer. More often than not, the reports are distorted because you'd have to eat an obscene amount of these foods to actually harm your body. With that being said, there has been solid evidence linking diets high in animal fats and low in fruits and vegetables to cancer...and guess who eats like that? Practically everyone in the western world! Making a few small changes in your diet can make a big difference - less meat and more fruits and vegetables!



• Environment.The day to day environment that a person lives in can affect whether they develop cancer at some point in their lives. Air pollution, excessive exposure to the sun, radiation (from food, the soil, buildings, work places, etc.), and a whole slew of other environmental factors can contribute to a person's risk for getting cancer. Keep in mind that the key here is "day to day" exposure - if you live in Alaska (very little sun exposure) and spend a week each year in Jamaica (lots of sun exposure), then you probably don't have to worry much about sun exposure being what causes cancer in your body. But wear sunscreen anyway!

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