Why Is Cancer on the Rise in People Under 50?

People often think of cancer as an older person’s disease. However, recent research shows that cancer in people younger than 50 has been on the rise for decades.

Early-onset cancers – those diagnosed before age 50 – began rising worldwide around 1990. A recent study by Brigham & Women’s Hospital shows increases in early-onset breast, colon, esophagus, kidney, liver and pancreas cancer, among others.

One reason for the rise in cancer diagnoses in younger people is better cancer screening and detection practices. However, researchers say certain risk factors are also increasing. These include being overweight or obese, excessive alcohol use, changes in our digestive tract, and not sleeping well.

Even when successfully treated, early-onset cancers can lead to long-term health problems. These include cardiovascular disease, infertility and other cancers later in life, in addition to quality of life challenges.

Excess Weight, Obesity & Cancer Risk

Being overweight or obese has long been known to cause changes in the body that can lead to cancer. These changes include chronic inflammation and abnormally high levels of insulin and other hormones. Cancer risk increases the more overweight or obese a person is and the longer they carry extra weight.

In early 2019, the American Cancer Society reported that obesity-related cancers were on the rise in people under 50. The research indicated that young people today are twice as likely to develop obesity-related cancers than several decades ago. These cancers include breast, esophageal, colorectal, gallbladder, stomach and kidney cancer.

The increase in obesity-related cancers in younger people is directly tied to a rise in obesity itself. Reasons for higher rates of obesity include:

• Sedentary lifestyles: More people today lead lifestyles that involve prolonged sitting and a lack of exercise.
• Western-style diet: Many people follow a Western-style diet – high in saturated fat, red meat, processed foods and sugar, while low in fruits, vegetables, whole grains and fiber.

Excessive Alcohol Use & Cancer Risk

Excessive alcohol use may play a role in the recent rise of cancer diagnoses in younger people. Alcohol is known to contribute to the development of cancer in three ways:

• Cell damage: Ethanol (pure alcohol) and its toxic by-product acetaldehyde can damage cells. It does so by binding with DNA and causing cells to replicate abnormally, leading to cancer.
• Changes in hormones: Alcohol can increase levels of certain hormones, including estrogen and insulin. These hormones can cause cells to divide more often, increasing the risk of cancer.
• Direct tissue damage: Irritation to the mouth, throat and other organs can increase the absorption of cancer-causing substances.

Changes to the Microbiome

The microbiome is the community of bacteria and microorganisms living in our gut. Research shows that the microbiome has changed over time in ways that may fuel the development of cancer. Since the mid-1900s, a number of risk factors for developing an unhealthy microbiome have increased, including:

• Excessive consumption of processed foods, alcohol and sugary beverages
• Obesity
• Lack of activity
• Type 2 diabetes

Of the 14 types of cancer that the Brigham and Women’s Hospital report found to be on the rise, eight were cancers related to the digestive system. This supports the theory that changes in the microbiome are contributing to the development of early-onset cancer.

Poor Sleep

Research has shown that adult sleep duration hasn’t drastically changed over the past several decades. However, children are getting far less sleep today than they did in the past. Studies have linked poor, disturbed sleep to increased risk for thyroid, breast, prostate and other cancers.

Other Factors

Other factors that may contribute to rising numbers of early-onset cancer include:

• Smoking, including secondhand smoke and exposure to a mother’s smoking while in the womb.
• Night shift work, which is associated with a higher rate of diabetes and obesity, both risk factors for cancer.
• Reproductive changes, including early menstruation, women delaying childbirth and having fewer children, and increased use of oral contraceptives.
• Lower breastfeeding rates and increased formula consumption.
• Environmental exposure, including exposure to air and water pollution.

In addition, the incidence of cancer in younger people is on the rise due to an increase in the impact of oncogenic viruses, which are viruses that can cause cancer. Oncogenic viruses include human papillomavirus (HPV) and hepatitis viruses. In recent years, HPV has caused a significant increase in early-onset head-and-neck, cervical and anal cancers, while hepatitis viruses have been linked to early-onset liver cancer. Vaccination for these viruses can potentially prevent the cancers associated with them.

The Good News

The good news is that despite the increase in early-onset cancers, overall cancer deaths have been on the decline. What’s more, many of the risk factors contributing to today’s higher levels of early-onset cancers are within our control. Healthy lifestyle choices can play a significant role in reducing your overall cancer risk.

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At University Hospitals Seidman Cancer Center, our care team offers the most advanced forms of cancer care, including prevention, screening, diagnosis, treatment and cancer survival support. Our disease-focused teams design personalized cancer treatment plans for every patient who entrusts their care to us. Learn more about cancer care at UH Seidman Cancer Center. Questions? Call the University Hospitals Cancer Information Service Line at 1-800-641-2422.