Today is Motivation Monday. I did the rower for a half an hour and used the standardized bike for an hour. Today is my half birthday. In honor of this occasion, the topic we will be discussing, why do cancer rates increase as we age?

As we age, our risk of developing cancer increases, now researchers at the University of Colorado Cancer Center say that this is because our tissue landscape changes as we age.

The study is published in the journal Oncogene.

A researcher at the University of Colorado Cancer Center explained:

An individual already accumulates a large percentage of the mutations they will have during their lifetime by the time they stop growing in their teens.

He explains: “There’s a mismatch between the mutation curve and the cancer curve, meaning that if cancer were due to reaching a tipping point of say, five or six mutations, we should see higher cancer rates in 20-year-olds, as this is when mutation rate is highest.”

Furthermore, healthy tissues are also full of oncogenic mutations. He says: “These mutations are many times more common than the cancers associated with them.” In other words, more mutations do not mean more cancer.

In addition, he explains that as humans have evolved, our bodies have had to develop new mechanisms to maintain our tissues and avoid disease.

He explains: “But we’re no better at preventing mutations than our yeast or bacteria cousins. You’d think if avoiding mutations was key to avoiding cancer, we’d be better at it than we are.”

He also argues that if these oncogenes were able to take over surrounding tissue, then introducing oncogenes into mice stem cells should help these cells survive instead of hurting them. He continued: “Rather stem cells harboring the oncogenes tend to get weeded out.”

The reason the risk of cancer increases with age is because the mechanisms that we have when we are younger to fight cancer deteriorate.

The body’s healthy cells function best for healthy, younger tissue conditions. When this balance is changed, for instance, through oncogenic mutation, the cells no longer represent the optimum fit for the surroundings, as healthy cells in young bodies quickly become more successful than cells with cancerous mutations.

He concluded: “When tissue is old, healthy cells are no longer a perfect fit, and mutations might help a cancer cell adapt in ways a healthy cell can’t.”