Why does our risk of cancer increase as we age?

Why does our risk of cancer increase as we age?


Here’s a sobering fact – the single greatest risk factor for getting cancer is aging.  Once past the age of 50, the risk increases substantially with half of all cancers diagnosed occurring after the age of 66.  In fact, the National Cancer Institute states that one quarter of cancer diagnoses are in people between the ages of 65 to 74.

Since time is always moving on and all of us are getting older day by day, it would be good to know, just why age is such a significant risk factor for developing cancer.  In other words, what’s age got to do with it?

It starts with our cells

The root cause of cells becoming cancerous appears to be mutations and other changes in our genome which is our complete set of DNA, including all of our genes.  Each genome contains all of the information needed to build and maintain us as we are.  The problem begins when mutations disrupt genes that regulate cell division and growth.  This disruption causes normal cells to grow uncontrollably.  What may start as a tiny trickle can with time become a flood of abnormal cells forming a tumor somewhere in the body.  Isn’t there anything to stop this mutation?  Not always as any additional mutations will further disable tumor-suppressing proteins which continue to feed the renegade cells. 

The aging body’s susceptibility to developing cancer

As to why an aging body makes us susceptible to developing cancer is not totally clear.  Views vary but one theory is that cancer develops in older people simply because of their prolonged exposure to carcinogens such as sunlight, radiation, environmental chemicals, and substances in foods we eat.  The other possibility already addressed has to do with random errors that occur when a cell’s DNA is copied before it divides.  This mutation can result in more cells accumulating more mutations the longer we live.

Other age-related factors that may play a role in cancer’s higher likelihood as we age include the following:

·      Long-term effects of chronic inflammation

·      Cancer-promoting DNA changes caused by oxygen free radicals

·      Less-effective DNA damage-repair mechanisms

·      Weakening immune system making it less efficient in detecting and attacking cancer cells

Is it only inevitable we will get cancer?

Before becoming depressed over the fact we can’t hold back the hands of time, researchers say they are still working on understanding the full picture of how aging and cancer are intertwined.  It doesn’t mean that as each birthday goes it is a given we’ll develop cancer. There are many people who live a long life who never do.  Plus researchers also say there are many things we can do to lessen our risk of a cancer diagnosis.  We can be “successful agers” by adopting some of the following healthy lifestyle changes as early in life as possible that can make a difference of a cancer diagnosis or not.  These lifestyle changes include quitting or never having smoked, eating a healthy diet, achieving and maintaining a healthy body weight, moderate use of alcohol if at all, reducing exposure to UV radiation from the sun, and regular physical activity. 

Every little healthy modification we do, all adds up over the course of our lives.  No one can predict who may or may not develop cancer.  But it is safer to err on the side of doing what it takes to get and stay healthy than to test fate by engaging in an unhealthy lifestyle.