제 30 호 Cancer Cases Surge Among People in Their 20s and 30s
Kicker: SCIENCE
Cancer Cases Surge Among People
in Their 20s and 30s
By Ji-Won Choi, reporter
Figure 1Colorectal and Thyroid Cancer Cases Among People in Their 20s and 30s
In recent years, cancer diagnoses among people in their 20s and 30s have increased rapidly, challenging the long-held belief that cancer is primarily a disease of older adults. According to data from the Health Insurance Review and Assessment Service, the number of thyroid cancer patients in their 20s and 30s reached 61,241 in 2024, a 14.0 percent increase from 2020. During the same period, the number of colorectal cancer patients rose from 3,633 to 6,599, representing a sharp increase of 81.6 percent. The rise in colorectal cancer among young adults has been especially striking. This trend is not limited to South Korea. A study published in the medical journal BMJ Oncology found that the number of early-onset cancer cases in people under the age of 50 worldwide increased by about 79 percent between 1990 and 2019. Researchers point to changes in lifestyle habits, including irregular sleep patterns, increased consumption of processed foods, lack of exercise, obesity, alcohol use, and chronic stress, as major contributing factors. Many young adults tend to dismiss early symptoms as simple fatigue or digestive problems because they consider themselves healthy. However, because early detection greatly improves treatment outcomes, people in their 20s and 30s should also pay close attention to their health and take steps to maintain healthier lifestyles.
Lifestyle Changes Behind the Rise
그림 1Ultra-Processed Foods
What is driving the increase in cancer among young adults? One of the main reasons is the change in dietary and lifestyle habits. In recent years, the consumption of delivery food and ultra-processed foods has increased, while the intake of fruits and vegetables has declined. Processed meats such as ham, sausages, and bacon contain nitrates and nitrites, which can be converted in the body into N-nitroso compounds, substances known to have carcinogenic potential. In addition, diets high in red meat and fat can alter the gut microbiome and cause chronic inflammation in the intestinal lining, increasing the risk of colorectal cancer.
Lack of exercise and obesity are also major risk factors. Fat tissue does more than simply store energy; it acts as a metabolic organ that releases inflammatory cytokines and hormones. When body fat accumulates excessively, chronic inflammation develops and insulin levels rise. These changes promote cell growth and suppress apoptosis, the natural process by which damaged cells are eliminated. As a result, abnormal cells are more likely to survive and multiply.
Irregular sleep patterns and frequent nighttime activity are also linked to cancer risk. Sleep deprivation reduces the secretion of melatonin, a hormone that regulates the body’s circadian rhythm. Melatonin has antioxidant properties and helps repair damaged cells. When melatonin levels decrease, the body’s ability to protect against DNA damage may weaken. In addition, alcohol is broken down into acetaldehyde, a substance that can directly damage DNA, while smoking exposes the body to numerous carcinogens that can cause genetic mutations. Taken together, the rise in cancer among young adults is likely the result of multiple lifestyle factors, including poor diet, obesity, insufficient sleep, alcohol consumption, and smoking, accumulating over time. Even if young people appear healthy on the outside, their everyday habits can trigger changes at the cellular level that increase the risk of cancer.
Stress and the Pressure of Modern Life
그림 2Stress and Cancer Risk
Chronic stress is also emerging as an important factor that may increase the risk of cancer among young adults. Many people in their 20s and 30s live under constant pressure from academic demands, job preparation, and financial concerns. When stress persists over time, the body releases high levels of stress hormones such as cortisol.If cortisol levels remain elevated for a prolonged period, immune function can weaken and the body’s ability to regulate inflammation may be impaired. Immune cells normally help detect and eliminate abnormal cells that develop in the body. When the immune system is compromised, this defense mechanism may not function properly. In addition, chronic stress can lead to unhealthy behaviors such as sleep disturbances, overeating, alcohol consumption, and smoking, all of which may further increase cancer risk.Another concern is that many young adults tend to ignore warning signs from their bodies. Symptoms such as fatigue, indigestion, and unexplained weight changes are often dismissed as temporary stress or poor condition. As a result, medical attention may be delayed. When health management is pushed aside in a busy daily routine, opportunities for early diagnosis can be missed.In this way, stress affects more than mental well-being. Through hormonal changes and weakened immune function, chronic stress can have a direct impact on physical health and may contribute to an increased risk of cancer.
Why Early Detection Matters
One reason cancer can be especially dangerous for young adults is that it is often diagnosed late. Many people in their 20s and 30s consider themselves healthy and tend to overlook symptoms such as abdominal pain, changes in bowel habits, unexplained weight loss, and persistent fatigue. These warning signs are often mistaken for stress or temporary digestive problems, which can delay medical attention. In addition, national cancer screening programs are primarily designed for middle-aged and older adults. For example, colorectal cancer screening in South Korea generally begins at age 40, meaning that most people in their 20s and 30s are not included in routine screening. As a result, young adults have fewer opportunities to detect cancer before symptoms appear. The problem is that cancer in young adults is often discovered at a more advanced stage. Being young does not necessarily mean that cancer progresses more slowly; in some cases, it can develop more aggressively. Therefore, early detection is crucial because it can significantly improve treatment outcomes and prognosis. If someone has a family history of cancer or experiences persistent symptoms such as changes in bowel habits, ongoing pain, or unexplained weight loss, they should consider undergoing medical evaluation even before reaching the recommended screening age. Paying attention to the body’s early warning signs is essential for protecting long-term health.
Cancer is no longer a disease limited to middle-aged and older adults. In particular, people in their 20s and 30s often do not perceive cancer as their own concern, which can lead to neglecting symptoms or delayed detection. Therefore, maintaining daily healthy habits is essential for both cancer prevention and early detection. Basic practices such as a balanced diet, regular physical activity, and sufficient sleep can help reduce the risk. In addition, if unusual bodily changes persist, it is important to seek medical evaluation regardless of age. Ultimately, health is not a concern limited to a specific period of life but a lifelong responsibility. Small differences in daily habits can significantly influence future health outcomes, making continuous attention and consistent practice essential.
Source:
https://www.news-medical.net/news/20250501/How-much-ultra-processed-food-is-too-much-This-study-has-the-answer.aspx
https://www.bbc.com/korean/articles/c3rw7j8ry51o
https://www.getnews.co.kr/news/articleView.html?idxno=860098
