Why are so many people getting cancer?

We are undoubtedly in the middle of what has been described as a “cancer epidemic”. The risk of contracting cancer has risen by over 10% over a single generation and is expected to increase by over 20% between 2010 and 2020. This means that in three years’ time there will be about 2 million people diagnosed with cancer every year in the US alone. These numbers mean that those of us who are alive today have a 50% chance of being diagnosed with cancer. Naturally, these facts are scary and as such they have drawn the attention of the media, generating sensational headlines and a variety of conspiracy theories. “Modern living”, cell phones, WiFi, pesticides, Big Pharma and a variety of other afflictions have all been blamed in the media and by a variety of truth-seekers (who also tend to be remedy-sellers). However, most of these theories seem to have missed out a key factor most epidemiologists credit for the steady increase in cancer cases over the past few decades.

In fact, what they seem to neglect is age. While of course plenty of young people and children are diagnosed with cancer, cancer is very much a disease of the elderly. Over 60% of all people diagnosed with cancer are over 65, even though the over-65s represent only about 15% of the population. This means that turning 65 statistically increases the risk over getting cancer by over 10-fold.  At the same time, the world’s population is increasingly ageing. The over-65s were only about 10% of the US population a few decades and are projected to raise to 20% over the next few years. An ageing population is undoubtedly a good thing, stemming from a variety of incredible medical advances. Less and less people are dying of heart disease  and stroke – and better healthcare is available to more and more people throughout the world. Since the elderly are at higher risk of cancer and more and more people are living to an older age, more people over-all are being diagnosed with cancer. Of course, this is not to deny that there are other factors impacting cancer epidemiology in recent years. For instance, the recent obesity epidemic undoubtedly plays a role in increasing the number of cancer cases diagnosed each year. However, the key role played by an ageing population is by far the most important factor to blame for the recent cancer epidemic.

The idea the scientific community tends to agree upon is that cancer is essentially unavoidable as the body ages – and therefore as people age they are more and more likely to be diagnosed with cancer. While there are many genetic and environmental factors that increase the risk of cancer, age eventually will catch up with all these other factors. Of course, this is not as flashy and satisfying as all the alleged culprits that have been put forth by popular newspapers. It is, however, very much rooted in truth. The reason why this idea is not as satisfying as, say, blame WiFi or mobile phones is that it is not something we can fix in our day-to-day lives. We can throw out our phones or stop eating non-organic food – but we cannot stop ageing. However, there are two crucial facts to take away from these results. First of all, while ageing is a key factor, there are many other environmental and genetic factors that play a huge role in driving up the risk of cancer. This means that by making smart choices – such as by quitting the use of tobacco, by maintaining a healthy weight and protecting oneself from cancer-inducing infections – anyone can significantly reduce the risk of cancer. Moreover, genetic testing is becoming an increasingly accessible tool to empower anyone to make smart decisions about their healthcare. For instance, testing for mutations in the BRCA1 and BRCA2 genes (which are associated with an increased risk of breast and ovarian cancer) can now inform decisions for women to undergo preventative surgery. Secondly, while number of cancer cases is increasing every year, so are the survival rates for patients diagnosed with most types of cancer. This means that for patients diagnosed today, the chances of completely recovering from cancer are better than ever. As we understand more and more about the biology that underlies cancer, the future for cancer patients is going to get even brighter.