A new review reveals evidence of a global cancer epidemic among those under the age of 50. Read to know what this means.
Research suggests the possibility of a global cancer epidemic
According to a recent analysis of cancer registry data from 44 countries, the incidence of early-onset cancers, including colorectal and 13 other cancers, many of which affect the digestive system, is rising quickly in many middle- and high-income countries.
The authors of the review claim that more sensitive testing for some cancer types, like thyroid cancer, is in part to blame for the increase in younger adults. According to co-author Shuji Ogino, a professor of pathology at the Harvard T.H. Chan School of Public Health, testing does not entirely explain the trend.
According to Ogino, the increase is the result of a dangerous concoction of risk factors, some of which are known and others of which require further investigation.
He points out that many of these risks, including obesity, inactivity, diabetes, alcohol, smoking, environmental pollution, Western diets high in red meat and added sugars, shift work, and lack of sleep, have been linked to cancer in the past.
Eight out of the 14 cancers studied involved the digestive system, according to Ogino, indicating a significant role in diet and the bacteria that live in our gut, known as the microbiome.
“I think this actually is an important piece because what it’s pointing to is changing exposure prevalences at early ages, that are producing earlier-onset cancers,” stated Dr. Elizabeth Platz. Dr. Platz is an epidemiologist at the Johns Hopkins Bloomberg School of Public Health. She was not a part of the study.
What is behind the spike in numbers?
However, as per Shuji Ogino, a co-author of the study, testing does not completely account for the trend. Ogino is also a professor of pathology at Harvard’s T.H. Chan School of Public Health. He added that the spike is also a result of unhealthy risk factors. Several factors such as smoking, obesity, environmental pollution, alcohol, inactivity, and diabetes are previously accounted for. Additionally, the Western diet, rich in added sugars and red meat in addition to shift work and low sleep also affects health.
For example, obesity, while once rare is a common occurrence now. Having a high body mass index (BMI) is a high risk for cancer and other diseases. The rise in obesity among younger adults and teens is leading to the earlier occurrence of diseases such as cancer. “And there are many unknown risk factors as well, like a pollutant or like food additives. Nobody knows,” added Ogino.
According to Ogino’s analysis, the average annual increase in young adults with colorectal cancer across the study’s years was about 2% in the US, Australia, Canada, France, and Japan. It is almost 3% annually in England, Scotland, and Wales of the UK. It is about 5% annually in Korea and Ecuador.
“It doesn’t seem big, but you can think about inflation: If it’s 2% every year, it’s going to be a big change in 10 years or 20 years, you know?” Ogino said. “It’s not trivial.”
Another recent study published in The New England Journal of Medicine found that between 1988 and 2015, those yearly increases caused the rate of early colorectal cancer to rise by 63%, from roughly 8 per 100,000 people to almost 13 per 100,000.
Approximately 1 in 10 cases of colorectal cancer in the US are found in patients between the ages of 20 and 50.