What Causes Cancer? | Why did I get Cancer?
Are we immune?
Why
Doc, why did I get this? I have led a healthy life.
We've been told if we don’t smoke, don’t drink, maintain a healthy weight, use sunscreen and eat right, we will not get cancer.
Well, unfortunately, none of us is safe from cancer. Cells in our body are continuously changing, dividing, and regenerating. Every time one of our cells divides, a new copy of DNA goes to each daughter cell. Errors occur during this duplication process, just as typos occur while we type. Cell’s proofreading mechanisms usually correct these typos. However, every once in a while, an error slips through (mutations). If these changes occur in certain specific areas of the genome, it leads to uncontrolled growth of cells leading to cancer.
Developement of normal cell to cancer cell
Broadly, many changes are required in succession before a cell turns cancerous. It would surprise you that such changes in our cells are a common occurrence. But we don’t get cancer because there are safety mechanisms (immune system) to check such rogue cells.
The reason for cells becoming cancerous and we developing cancer are many. Though there is a long list, we can sum it up into:
Genes
All the information of a cell is contained in its DNA. Some people have genes that make them prone to developing cancer. This defect can be transmitted from the family or can arise at birth.
Environment
As we go about our life, we expose ourselves and our cells to so many things. The food we eat, the water we drink, the air (polluted) we breathe, the sunlight we enjoy in the winter, the wine we enjoy with dinner, and so forth. Any of these can cause a change in the DNA of cells and facilitate cancer development.
Smoking, tobacco, alcohol and obesity cause a sizable chunk of cancers globally. Tobacco causes at least 20 cancer types and 25% of all cancer deaths globally. The world today is struggling with obesity and a sedentary lifestyle. Obesity makes you prone to many cancers. The risk of cancer increases continuously with increasing weight.
Increasing age
All these changes accumulate with time and that’s the reason we have an increased risk of getting cancer with increasing age.
And then the ultimate reason
Bad luck
Despite all this, the ultimate reason we get cancer is bad luck. The reasons we enumerated above facilitate cells becoming rogue. An unlucky normal cell can develop into a cancer cell even in their absence. Bad luck is also required to complete the cycle when these risk factors are present.
Research from Johns Hopkins showed that two-thirds of cancer-causing genetic mutations arise from “bad luck”. The researchers concluded that DNA-copying mistakes are responsible for 66 percent of the mutations, while 29 percent are because of environmental factors and 5 percent to heredity.
Siddhartha Mukherjee summed it up brilliantly. “Cancer equals heredity plus environment plus triggers plus chance.”
Risk factors
Risk factors are something that increase the chance of someone getting a disease. Genetic, environmental and increasing age are risk factors. More the number of risk factors–higher the likelihood.
Though someone with a risk factor has a higher chance of getting cancer. But the presence of a risk factor does not mean that the person will always get the disease. While some people will get the disease even in the absence of risk factors.
We can use the analogy of a highway. If you drive rashly, the chances of an accident are higher. But driving safely does not guarantee that we won’t get into an accident.
So, anyone can get cancer on the highway of life.
What to do?
Though we cannot eliminate the danger of cancer, we can reduce it. Roughly 42 percent of cancers are preventable by not smoking or drinking, maintaining a healthy weight, regularly exercising and not being exposed to cancer-causing pollutants.
If you drive carefully you can decrease your chance of getting into an accident.
Stay Alert! Stay Healthy! Happy Living!
