Somewhere between 5% and 10% of cancers can run in families, data shows, meaning they have a genetic component. Some of the most common genetically linked cancers are those of the breast, colon, prostate, ovaries and uterus.
However, people who are able to maintain a healthy lifestyle over the long term, such as not smoking and drinking only moderately, maintaining a low body mass index, eating a nutritious diet and exercising regularly, can also decrease their incidence of cancer – even those who are at the highest genetic risk of one or more cancers, Chinese scientists have found.
They used data from more than 400,000 adults who participated in the UK Biobank, a major worldwide source of in-depth genetic, health and lifestyle information. Then they applied statistical methods to create an overall “cancer polygenic risk score” (CPRS) for 16 types of cancer in men and 18 in women, for every individual in the group.
Overall, the combination of high genetic cancer risk and poor lifestyle habits made receiving a cancer diagnosis three times more likely in men, and 2.4 times more likely in women, than being at low genetic risk and maintaining healthy lifestyles.
Among people at the highest CPRS levels, the actual incidence of cancer over a five-year period was 7.2% in men and 5.8% in women for those who followed the fewest healthy behaviors. For those at high risk who led the healthiest lifestyles, cancer incidence was 5.5% in men and 3.7% in women. Similar trends were observed in all other genetic risk categories, suggesting that adults can benefit from a healthy lifestyle regardless of their genetic risk.
Notably, nearly every adult included in the study (97%) had a high genetic risk of at least one type of cancer. “This suggests that almost everyone is susceptible to at least one type of cancer… It further indicates the importance of adherence to a healthy lifestyle for everyone,” the study’s authors said.
The study was published in Cancer Research.