Accelerated Biological Aging Emerges as Key to Surge in Cancer Among People in Their 40s

As cancer incidence among younger generations rises rapidly worldwide, accelerated biological aging has been identified as a key contributing factor.

An analysis by a research team at Washington University of data from more than 148,000 participants in the UK Biobank found that aging in specific organs increased the risk of early-onset cancer by as much as 89%. The finding is notable because it suggests that the phenomenon in which cells and organs age more rapidly due to environmental factors such as diet, stress and insufficient sleep—regardless of chronological age—may be a decisive backdrop to cancer development.

According to Global Burden of Disease (GBD) data published in BMJ Oncology, the number of early-onset cancer cases worldwide among people younger than 50 increased 79.1%, from 1.82 million in 1990 to 3.26 million in 2019. The US Centers for Disease Control and Prevention (CDC) and BMJ have noted that the rising trend in early-onset cancer precisely coincides with the rising trend in obesity-related cancers.

■ Aging of the immune system and adipose tissue directly raises lung and colorectal cancer risk

A study analyzing data from approximately 160,000 people quantified the association between organ-specific aging and the risk of developing specific cancers. Aging of the immune system increased the risk of early-onset lung cancer by 89% (hazard ratio, 1.89), while aging of adipose tissue increased the risk of early-onset colorectal cancer by 60% (hazard ratio, 1.60). Accelerated biological aging throughout the body was also associated with an 8% increase in the risk of early-onset solid cancers.

Differences between groups based on the rate of aging were also clear. The group with the fastest biological aging had a 15% higher cancer risk than the group with the slowest aging, with the difference particularly pronounced for lung, colorectal and endometrial cancers. Comparisons between generations also showed that people born after 1965 were 17% more likely to have accelerated biological aging than those born in the early 1950s.

■ Ultra-processed foods and obesity are key drivers of organ aging

Consumption of ultra-processed foods and obesity are cited as major causes of accelerated biological aging. Various additives and refined carbohydrates in ultra-processed foods disrupt the gut microbial ecosystem, leading to breakdown of the intestinal barrier, chronic systemic inflammation and impaired immune function. The BMJ Oncology global research team analyzed that a diet high in red meat and sodium and low in fruit, along with alcohol consumption, smoking, insufficient physical activity and high blood glucose, collectively accelerates biological aging.

When the gut environment deteriorates, immune function that monitors and eliminates cancer cells weakens. As myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) increase, an immunosuppressive environment develops. Research showing that a liver with fatty liver disease (hepatic steatosis) is biologically older and causes more lethal types of liver metastases also supports this finding. This is consistent with the “seed and soil hypothesis,” which holds that cancer cells, the “seeds,” need aged organs, the “soil,” to grow.

■ South Korea has the world’s highest rate of colorectal cancer among young adults

The implications of this research for South Korea are significant. According to data from the global medical journal The Lancet and South Korean health care sources, the colorectal cancer incidence rate among South Koreans aged 20 to 49 is 12.9 per 100,000 people, the highest in the world. That exceeds the rates in the United States (10) and Australia (11.2). In breast cancer, most patients in Western countries are in their 60s and 70s, whereas in South Korea, patients aged 40 or younger account for approximately 38% of all patients, indicating a serious level of cancer incidence among younger women.

Analysts say these trends reflect the combined effects of the rapid adoption of Westernized dietary habits, work environments that require long hours of sitting, and insufficient sleep and chronic stress stemming from a highly competitive society. These factors are believed to be accelerating organ aging and disrupting the gut microbial ecosystem among South Korea’s younger generations.

Louis Tian, a researcher at Washington University School of Medicine, said, “Unlike chronological age, biological age can be modified by diet, physical activity, mental health and environmental stressors,” adding, “Understanding the mechanisms of biological aging will be key to improving cancer prevention and early detection among younger generations.”

Changes to cancer screening systems are also expected. Most countries currently begin screening based on chronological age, such as 40 or 50 years. However, personalized preventive medicine may be introduced in which blood biomarkers, including proteins and inflammatory markers, are used to measure “biological age” first and select people in their 20s and 30s with rapid organ aging for screening. Unlike genetic factors, biological aging is an area that can be reversed or slowed through individual efforts and public health policies. As a result, regulation of ultra-processed foods, restoration of microbiome health and management of chronic inflammation are expected to become key trends in the health care industry.