Global Health

Why is cancer becoming more common among millennials?

Young adults are at a higher risk of early-onset cancer than middle aged people and older generations.

Young adults are at a higher risk of early-onset cancer than middle aged people and older generations. Image: REUTERS/Nir Elias

Gabi Thesing
Senior Writer, Forum Agenda
Our Impact
What's the World Economic Forum doing to accelerate action on Global Health?
The Big Picture
Explore and monitor how Global Health is affecting economies, industries and global issues
A hand holding a looking glass by a lake
Crowdsource Innovation
Get involved with our crowdsourced digital platform to deliver impact at scale
Stay up to date:

Global Health

This article is part of: Centre for Health and Healthcare

Listen to the article

  • A recent study has confirmed an alarming increase in early-onset cancers in millennials.
  • A Western diet of processed food and a sedentary lifestyle are possible contributors, the researchers say.
  • Non-communicable diseases, including cancer, now account for 41 million global deaths every year, according to the World Economic Forum’s Global Health and Healthcare report.

It’s long been known that processed foods and a sedentary lifestyle are not good for us, but a new study has confirmed a possible link between them and an alarming increase in early-onset cancer among millennials.

Over the past 30 years, cancer rates in the G20 nations have increased faster for 25- to 29-year-olds than any other age group – by 22% between 1990 and 2019, according to the Financial Times (FT). The UK newspaper analyzed data from the Institute for Health Metrics and Evaluation at the University of Washington School of Medicine and found that cancer diagnoses for 20- to 34-year-olds in these Western countries are now at their highest level in three decades. Meanwhile, cancer cases in those over 75 have declined since 2005.

Apart from the sometimes tragic health consequences of these early-onset diagnoses, there are also long-term policy implications: the estimated global cost of cancer from 2020 to 2050 is $25.2tn at constant 2017 prices. This is “equivalent to an annual tax of 0.55% on global gross domestic product,’’ the researchers said.


What is the World Economic Forum doing to improve healthcare systems?

Why are more millennials getting cancer?

So what is causing this surge in numbers? While earlier detection plays a part, the FT analysis and a number of other recent studies say changes in nutrition including eating more processed food, a more sedentary lifestyle and exposure to more environmental risk factors such as toxins are likely to play a big part.

The Western lifestyle changed dramatically in the 1950s and ’60s and children born from then on will have been exposed to these changes from a very young age, something scientists call the “birth cohort effect” – where each successive generation has a higher risk of developing cancer later in life.

“People born in 1960 experienced higher cancer risk before they turn 50 than people born in 1950, and we predict that this risk level will continue to climb in successive generations,’’ said Shuji Ogino, a professor at Harvard Chan School and Harvard Medical School and the co-author of a groundbreaking study into early-onset cancers.

Figure showing the individual life-course exposures and their relationship with the development of early-onset cancers.
Poor diet and a sedentary lifestyle are possible factors behind the rise in early-onset cancers. Image: Nature

How diet plays a part

Ogino and colleagues analyzed global data on 14 cancer types that were becoming more common in younger adults. Possible risk factors for early-onset cancer were identified as a highly processed food, an increase in sugary drinks and alcohol.

In the US, over 60% of calories eaten are now ultra-processed, while in the UK it’s 57%, the highest in Europe, according to Prof Tim Spector and Dr Chris van Tulleken, experts on the impact of ultra processed foods on the microbiome. Our microbiome produces vitamins, regulates our immune system and helps digest food.

An unhealthy microbiome altered by diet, lifestyle and antibiotic use can be ”another notable contributor to tumour development”, according to the Ogino study. It has found that among the 14 early-onset cancers, eight relate to the digestive system, “indicating the pathogenic importance of both the oral and intestinal microbiome”.


As developing countries catch up in wealth, they also tend to emulate Western-style diets and lifestyles – which is leading to rising cancer rates among people under 50, according to the FT analysis. It found that between 1990 and 2019, cancer rates for 15- to 39-year-olds increased significantly faster in upper-middle-income countries, such as Brazil, Russia, China and South Africa, compared to high-income countries: by 53% compared to 19%.

Figure showing the broad implications and benefits of prevention efforts for early-onset cancers.
Collaborative approaches can help combat the increase in early-onset cancers. Image: Nature

What are the solutions?

Without interventions and preventive measures, the prognosis is not good for future generations. Already the current cohort of young adults has a higher risk of early-onset cancer than the middle age and older generation.

As well as calling for more research and raising awareness of the benefits of a healthy lifestyle and diet, Ogino’s study says policy interventions such as “regulation of industries that produce tobacco, ultra processed foods and beverages could potentially have an effect on cancer risk”.

Meanwhile, some clinicians are calling for a reduction in eligibility age for cancer screening programmes, reports the FT.

With non-communicable diseases, including cancer, now accounting for 41 million global deaths every year, “it is important to ensure stakeholders, industries, countries, and sectors strive to achieve common health and healthcare goals and work collaboratively to do so,” the World Economic Forum points out in its report, Global Health and Healthcare Strategic Outlook: Shaping the Future of Health and Healthcare.

Have you read?
Don't miss any update on this topic

Create a free account and access your personalized content collection with our latest publications and analyses.

Sign up for free

License and Republishing

World Economic Forum articles may be republished in accordance with the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License, and in accordance with our Terms of Use.

The views expressed in this article are those of the author alone and not the World Economic Forum.

Related topics:
Global HealthHealth and Healthcare
World Economic Forum logo
Global Agenda

The Agenda Weekly

A weekly update of the most important issues driving the global agenda

Subscribe today

You can unsubscribe at any time using the link in our emails. For more details, review our privacy policy.

Promoting healthy habit formation is key to improving public health. Here's why

Adrian Gore

April 15, 2024

About Us



Partners & Members

  • Join Us

Language Editions

Privacy Policy & Terms of Service

© 2024 World Economic Forum