Cancers in Young Americans: Same Cancers But Earlier and More Common Than in Their Elders

Are younger generations at greater risk of cancer than those before them? A new study published in the journal The Lancet Public Health provides a troubling answer to this question. Led by epidemiologist Hyuna Sung of the American Cancer Society, this research reveals that people born in the 1980s and 1990s in the United States are more likely to develop cancer at a younger age than their elders. This increase in cancers among young people cannot be attributed solely to the aging of the population, but reflects profound changes in our lifestyles and our environment.

A worrying trend

The study shows a marked increase in the incidence of certain cancers, particularly those linked to pollution, diet and modern lifestyles. Unlike tobacco-related cancers, the incidence of which has decreased thanks to prevention campaigns and the reduction of smoking, other types of cancer, such as those of the digestive system, are increasing at a worrying rate.

Colorectal cancer has traditionally been considered a disease that affects mainly older people. Historically, it most commonly occurs in individuals aged 50 and over, with peak incidence around the ages of 60 to 70.

• Historic incidence peak : between 60 and 70 years old.
• Age at which screening is generally recommended : 50 years (in many countries).

In recent decades, there has been an increase in the incidence of colorectal cancer in young adults, that is, people under the age of 50. Although this cancer is still more common in older people, it is now increasingly diagnosed in people aged 20 to 49. According to the study, people born in the 1990s are twice as likely to develop colorectal cancer as those born in the 1950s.

• Young adults (20-49 years old) : significant increase in incidence. This worrying trend is currently being studied, but it appears to be due to a combination of lifestyle, dietary, and possibly genetic or environmental factors.
• Average age of diagnosis in young adults : often diagnosed in the forties, but cases occur even in people in their twenties and thirties.

In response to this trend, some screening recommendations have been revised downward, and it is now recommended to start screening as early as age 45 in some countries.

Similarly, stomach and pancreatic cancers, also rare among young people in the past, are becoming increasingly common.

The underlying causes

This increase in cancers of the ” eighty and ninety boomers ” is not only due to improved diagnostics or longer life expectancy. It is also linked to environmental and behavioral factors that have changed over time. The modern diet, rich in ultra-processed foods, added sugars and saturated fats, plays a crucial role. The eating habits of the younger generations differ considerably from those of their elders, with increased consumption of fast food and sugary drinks.

Air pollution is another factor of concern. Exposure to air pollutants, particularly in urban areas, has been associated with an increased risk of cancers, particularly of the respiratory tract. Younger generations, growing up in increasingly industrialized environments, are exposed to these carcinogens from an early age.

Finally, a sedentary lifestyle, with increased screen time and reduced physical activity, also contributes to increased risk. Overweight and obesity, increasingly common among young people, are well-known risk factors for several types of cancer.

A call to action

Faced with this alarming situation, governments, health professionals and civil society must work together to reverse this worrying trend. Raising awareness among younger generations about the risks associated with their lifestyle is crucial.

In addition, this study highlights the importance of early and regular screening to detect cancers at a stage when they are more easily treatable. Young adults should be encouraged to see their doctor regularly and undergo appropriate screening tests.

Most Common Cancers Among Young Americans

According to the study conducted by Hyuna Sung and her team, the cancers that are particularly on the rise among the younger generations in the United States are cancers of the digestive system. Colorectal, stomach and pancreatic cancers show a notable increase. In addition, thyroid and kidney cancers are also increasingly common among young adults. These trends suggest that environmental and lifestyle factors, such as diet, pollution and sedentary lifestyle, play an important role in the emergence of these cancers.

The most common cancers among young French people

In France, younger generations are not spared from the rise in cancers, although the figures remain less alarming than in the United States. According to data from the National Cancer Institute (INCa), the most common cancers among young adults (aged 15 to 39) are:

• Breast cancer : it represents approximately 20% of cancers diagnosed in young women. Each year, more than 1,500 new cases are detected in women under 40.
• Colon and rectal cancer : although rarer in young people, its incidence is slowly increasing, with around 300 new cases per year in those under 40.
• Thyroid cancer : this type of cancer is increasing sharply, particularly among young women. Around 1,000 new cases are recorded each year among those under 40.
• Melanomas : This type of skin cancer is also on the rise, with nearly 500 new cases annually among young adults.

These figures highlight the importance of prevention and early detection of these cancers, which increasingly affect younger generations in France.

Editorial

Adapting clinical practices and prevention recommendations

In recent decades, we have witnessed a worrying evolution in the distribution of colorectal cancer cases. Once considered a pathology essentially linked to aging, this cancer appeared mainly in individuals aged 50 and over, with a maximum incidence generally observed between 60 and 70 years. It is in this age group that the majority of cases were historically diagnosed, which led to the establishment of screening recommendations starting at the age of 50, a preventive measure that proved to be in line with the observed risk profiles.

However, recent epidemiological trends show a disturbing shift in this dynamic. Indeed, an increasing number of colorectal cancer cases are now being diagnosed in younger adults, particularly those under 50 years of age. This trend is particularly concerning because it represents a significant departure from traditional epidemiological patterns. Even more alarming, this increase in cases among young adults, often defined as those aged 20 to 49, does not appear to be linked to a single identifiable cause, but rather to a confluence of factors.

Modern lifestyles, marked by low-fiber diets, increased consumption of red and processed meats, lack of physical activity, and increased prevalence of obesity, are widely considered potential contributors to this increase. In addition, environmental and genetic factors, which are still poorly understood, may also play a role. The impact of these changes on public health is such that several health organizations have begun to lower the recommended age for colorectal cancer screening, suggesting that screening should begin as early as age 45, or even earlier for individuals with risk factors.

It is crucial that this trend be taken seriously by the medical community and that research efforts be intensified to better understand the mechanisms underlying this rise in the incidence of colorectal cancer in young adults. In addition, it is essential to raise awareness among the general public, and in particular among younger generations, about the potential risks associated with colorectal cancer, as well as the importance of early detection.

Although colorectal cancer remains more common in older adults, it is now imperative to recognize the emergence of this disease among younger populations. It is the responsibility of health professionals to adapt their clinical practices and prevention recommendations according to these new realities to best protect the health of patients.

Thierry Borsa