Eat a healthy, plant-based diet. Exercise daily. Don’t smoke. Minimize alcohol consumption. Apply sunscreen religiously.
These are all tips that experts claim reduce one’s overall life-time risk of developing most cancers. While some of these are true — for instance, by not smoking, you can reduce your risk of developing lung cancer substantially, and daily sunscreen application does help reduce your risk of common skin cancers by 40% to 50% — the unfortunate truth is that most cancer-combatting efforts have minimal to no impact.
According to findings from a Johns Hopkins University study, as many as two-thirds of all cancer cases in adults can be attributed to random gene mutations that trigger tumour growth. What this means is that just one-third of cancer cases are due to environmental, lifestyle or genetic factors, while the remaining two-thirds are the result of plain old bad luck.
To say that two-thirds of cancer cases are the result of random cell mutations may seem insensitive to some, but researchers behind the Johns Hopkins’ study made sure they were thorough before they made such a bold assertion. To come to their conclusions, the researchers followed the number of cell divisions that occurred among 31 types of tissue, including the pancreas and small intestine. They then compared these numbers against the lifetime cancer risks of American adults. What they found was that the higher number of mutations a tissue endures, the more likely said tissue is to develop cancer. In other words, the number of times stem cells divide within a certain type of tissue has a direct correlation with a person’s cancer risk within that tissue, as the more cell divisions that happen, the higher the chance of a random mutation occurring.
If random cell mutations are responsible for cancer, does that mean you should give up on healthy living as a cancer-fighting tool? Not necessarily.
Though 22 cancer types are largely driven by random mutations, researchers found that nine are connected to environmental factors you can partially control. Among those nine include cancers of the neck and head, lung cancer and colorectal cancer. Factors that play a role in these nine may include UV rays, smoking, alcohol use and chemical exposure.
Also among the nine cancers are cancers that are influenced by hereditary factors. Though you cannot control hereditary factors, you can undergo regular screenings to identify tumours early on and before they become life-threatening.
To better understand the one-third of cancers that are not caused by random mutations, consider the following.
All cancers develop because something has gone wrong with one or more genes in a cell. That “something” is referred to as a gene “fault” or “mutation.” These faults cause cells to stop working properly, become cancerous and start dividing and growing uncontrollably. Most gene faults develop during one’s lifetime and typically with age. As the body gets older, random mistakes during cell division become more likely. These gene faults are not hereditary and cannot be passed to one’s children.
That said, gene faults can be passed from parent to child. This is uncommon, with genetic specialists estimating that between just five and 10 of every 100 cancer cases are linked to inherited faulty genes. That means that 5% to 10% of all cancers are influenced by genetics.
In the rare case that a parent does have a faulty gene he or she can pass on, the likelihood of him or her passing it on is one in two, or 50%. If a child does inherit a faulty gene, he or she will not automatically develop cancer. Rather, the gene simply increases his or her risk of developing certain types of cancer in his or her lifetime. Researchers have also found that persons with inherited faulty genes are more likely than others to develop cancer at a young age.
If you have an extensive family history of cancer, you may wonder if you have an increased risk of inheriting a faulty gene. Researchers say it is unlikely, as cancer is common, especially in older people. One study estimates that as many as one in two individuals over the age of 60 will develop some type of cancer at some point.
However, if you have a strong family history of a certain type of cancer, you may have an increased risk of inheriting the faulty gene that causes it. Your risk depends on the following:
The more closely related you are to the affected individuals, and the younger the average age of diagnosis, the stronger your family history becomes.
Though everyone experiences cell division on an ongoing basis, and though mutations can happen to anyone, ongoing research does suggest that “random mutations” are not so random after all. Earlier studies have shown that healthy lifestyle choices help to “turn off” cancer-promoter genes while “turning on” cancer suppressor genes. More recent studies reveal that mutation rates are higher in persons who regularly expose themselves to toxins and lower in those who lead a health-conscious lifestyle. Below are just a few factors that seem to have the greatest influence on cell mutation and cancer risks.
In an ongoing attempt to understand why some smokers develop lung cancer and others do not, researchers found that lung cell mutations are far more common in smokers than in non-smokers. The increased risk of mutations, researchers confirmed, directly correlates with an increased risk of lung cancer. This is why, they concluded, that so few non-smokers ever develop lung cancer, whereas 10% to 20% of smokers do.
What is more, another study found, is that the frequency of cell mutation increased in a straight line with the number of pack years of smoking — a pack year being the number of packs a person smokes per day multiplied by the number of years he or she smoked. However, the rise in mutations stopped after 23 pack years of exposure.
Another interesting find is that the heaviest smokers did not necessarily have the highest number of mutations. Despite heavy smoking, many individuals in the study managed to suppress further mutation accumulation, which researchers attribute to proficient bodily systems that either detoxify cigarette smoke or efficiently repair DNA damage. The existence of such systems also explain why some smokers develop lung cancer and others do not.
Though cell mutations are random for the most part, research does not discount the cancer-fighting effects of a healthy diet, physical activity and other good lifestyle choices. In fact, according to the World Cancer Research Fund, approximately 18% of all cancer cases worldwide can be attributed to physical inactivity, high levels of body fat, alcohol consumption and/or poor nutrition. Given this data, some actionable steps you can take to keep cell mutations to a minimum and, therefore, reduce your cancer risk, are as follows:
Worldwide, infections are associated with 15% to 20% of all cancers. This rate is even higher in developing countries but lower in already developed countries, such as the United States.
Infections increase cancer risk in multiple ways. Those are as follows:
Though it is not possible to prevent all types of infections, there are certain lifestyle choices that may increase a person’s risk for certain infections and viruses. For instance, unprotected sex, intravenous drug use, excessive alcohol consumption, travel without taking proper precautions, lack of hygiene and avoidance of medical care can all increase your risk of developing an infection.
Unfortunately, most cancers are random occurrences that can develop in even the healthiest of individuals. However, healthy lifestyle choices can minimize cell division and, in the process, the risk of mutations occurring. Additionally, regular screenings can go a long way toward identifying tumours before they become malignant. While no one can prevent cancer entirely, they can take steps to minimize their risk and, in the process, lead a healthy, wholesome life.