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In almost every region of the world, overweight and obesity among children and adolescents is a public health problem. There has been no progress in stemming the rate of overweight and obesity in children under 5 years in nearly 20 years, according to the World Health Organization (WHO).

This is a problem, because we know that when people live with overweight or obesity near the start of their lives, it often becomes a challenge throughout their adult lives.

What’s the problem with being inactive?

Young people may not be thinking very much about their risk of developing cancer. But the habits laid down in youth can last a lifetime. Our evidence shows that being active reduces the risk of colon (part of the bowel), post-menopausal breast and womb cancers.

Perhaps more importantly, being physically active also helps reduce our risk of living with overweight and obesity – a cause of at least 13 different types of cancer. Put simply, excess weight results from an imbalance between the energy we take in through our diet, and the energy we expend through being active (and other bodily functions). While we need to consider wider issues related to our ability to access a healthy diet, and managing stress and sleep levels, part of the solution involves being more active.

Are screens a particular problem?

Screens, and particularly mobile phones, have been blamed for a range of social and health problems among young people, including:

• short-sightedness
• mental ill health
• bullying
• poor sleep

Evidence from our 2018 Diet and Cancer Report revealed convincing evidence that more screen time for children (from mobile phones but also using computers at school and watching devices during leisure time) makes weight gain more likely, as well as overweight and obesity.

The reasons for this are mixed. We tend to watch screens while sitting down, which uses less energy. Watching screens can also encourage us to eat more than is needed, not least because of exposure to adverts for unhealthy food and drinks, which young people may be particularly susceptible to.

The WHO lists limiting screen time as one of the ways to prevent and manage overweight and obesity in young people – but it’s only one.

What are the barriers to getting more active?

Young people’s experiences differ but, looking at the evidence and talking to parents and teenagers in the UK, a few common problems are highlighted:

• Underfunded / poor-quality equipment in public spaces (that may also feel unsafe to use).
• Cost – young people often don’t have a steady income, and gyms/clubs/sports can be expensive. Young people need access to parks and sports fields in their neighbourhoods.
• Travel – young people are often dependent on others for travel, which makes active travel – including safe routes to walk or cycle to school – and good public transport infrastructure so important (see below).
• Lack of options – children and young people in the UK are often offered activities such as football, netball and cross-country, but many want to try out less conventional sports such as yoga, dodgeball or trampolining.
• Gender – there is a significant decline in young girls taking part in sport, and parents of girls highlighted particular barriers to participation around body image, concerns about sweating and clothing, and lack of private changing spaces.

Elsewhere, a 2022 study looking at Botswana, Ethiopia, South Africa and Zimbabwe identified barriers around funding, but also highlighted community safety and a general lack of infrastructure as challenges.

What solutions are working around the world?

When developing ideas and designing policies to tackle overweight and obesity among children and young people, one voice is often unheard – that of young people themselves. From 2018–23, World Cancer Research Fund was involved in an innovative EU-funded project called CO-CREATE, which aimed to change that by putting young people at the forefront of tackling the obesity epidemic in Europe. The youth representatives on the project came up with 4 demands to policymakers, including “Offer all children and adolescents free, organized physical activities at least once every week.”

Using what they learned as part of the CO-CREATE project, our Policy team have devised a policy factsheet on physical activity, outlining the best ways to meet our Cancer Prevention Recommendation to be physically active.

Of all the information in the factsheet, some policy recommendations would specifically benefit children and young people, if acted on by governments around the world. These include:

• Initiatives that optimise opportunities for physical activity (including walking and cycling to and from school).
• Active play before and after school, as well as during recess and lunch breaks.
• Reduce sitting during classes.
• Policies to priorities active urban design, like ensuring access to open/green space or walking and cycling infrastructure where people live.

To keep people informed about both the need to be active, and the opportunities available to them, we also recommend:

• High quality physical education in school curricula.
• Enhanced physical activity training for all teachers.

And some of these innovative policies are already being undertaken in parts of the world. There are many policies recorded in our MOVING database mandating physical activity in schools, broadly ranging from 2–4 hours per week, depending on age and country.

And it’s not just dedicated PE sessions. Italy’s Scuola attiva kids aims to promote a culture of wellbeing and movement among not only students but teachers and families as well. In Finland, the Students on the Move programme encourages young people to sit less and move between breaks. Belgium’s Adventurous Activity initiative offers young people the chance to try out high and low ropes, tree climbing, rowing, BMX, skiing and orienteering.

Yet parents we spoke to suggested that there also needs to be a reframing of how PE is seen in school. One parent in Surrey, UK, said: “If you’re really good, you tend to do loads as part of a club, but there seems to be very little for those who aren’t any good.”

“There’s different aspects of sports. There’s one where you’re trying to create lifelong fitness for young people to engage in sport as part of a healthy lifestyle. And there’s another part where you need competitive sport to provide appropriate challenge” – Jennifer Cole, teacher and parent of 3, Brunei

“Emphasise fun so everyone can join in. Let people compete and win something but focus on beating personal bests rather than being top of the class so it’s not exclusive. Why not offer points or vouchers for those who increase their steps the most, not the ones with the overall highest numbers, so you’re encouraging people who don’t do anything?” – Mike, parent of 3 including 2 teenage girls, UK

Active travel was another key concern for parents – and is also one of our policy recommendations, including:

• Transport policies, systems and infrastructure that prioritise walking, cycling and use of public transport.
• Road safety actions for pedestrians and cyclists.

Active travel, which has the additional benefit of helping countries meet climate commitments, is already being promoted in many European countries. Austria’s Kindergarten Mobility Box aims to make walking and cycling the norm from a young age, and Belgium has similar scheme.

Perhaps, rather than just focusing on crisis-driven solutions to an increasingly inactive world, we need to listen more to young people about the changes they want to see in their world, alongside implementing policies that make it easier for everyone – especially young people – to move more and sit less as part of their everyday lives.

Siobhan McGeown

Siobhan was inspired to run by her parents (in main picture), who have both had cancer. She says: “After watching both my parents suffer from cancer (ovarian and prostate), as well as several other close family members, I want nothing more than to see better outcomes for cancer diagnoses, as well as better detection and testing before it gets to that stage.”

Angela Brooks (left, wearing cap)

Angela was diagnosed with breast cancer in 2021 aged only 33. ​She’s currently in remission but still living with the impact of cancer, including early menopause​. Angela told us about her training schedule: “Every 3 weeks, between rounds of chemotherapy, I set myself the goal of completing a 10k run.”

Sam Burton

Sam says: “The decision to run for World Cancer Research Fund is driven by my Father’s recent diagnosis with kidney cancer, an event that has reshaped my perspective on life and illuminated the critical importance of cancer research and advocacy.​”

Jack Gibbons and family

Jack Gibbons

This is Jack’s second marathon for us, having also run in 2018. He’s running in memory of his mum, Maggie, who received a diagnosis of very aggressive stage IV melanoma in late 2023 and passed away in January 2024.

Maggie was there to support Jack when he ran his first marathon and was there at the finish line of the London Landmarks half in 2023 to see him over the line. Her support meant the world to Jack and he’s proud to be able to run for her in 2025 and raise money for World Cancer Research Fund.

David Herlihy

David sadly lost his Dad to cancer in April 2024, and his Mum has been diagnosed with cancer for the second time in 5 years​. He’s dedicated to health and fitness, and has completed 5 marathons, an ironman and 2 ultra marathons​.

Hannah Stedman

Hannah is running in memory of her amazing Mum, who “had a very quick battle with lung cancer in October 2023. She was diagnosed on the 3rd and had passed by the 24th. To say this experience was the hardest thing of my life is an understatement.”​

George White

George is a mortgage broker based in the West Midlands and is motivated to run for us after recently losing his Godfather to cancer.

The International Agency for Research on Cancer estimates that, by 2050, the world will see 35 million new cancer cases each year, up by 15 million annual cases in 2022. Yet with the right policies to prevent cancer, 14 million of those people could avoid their diagnosis. These policies would need to address a variety of factors, including tobacco, alcohol, overweight and obesity, breastfeeding and unhealthy diet.

Cancer places increasing burden on society

As the cancer burden increases, the strain on our health systems, economies and families becomes harder to meet. Unhealthy weight – just one risk factor – is projected to cost the global economy more than $4 trillion a year by 2035. Our food systems make eating a healthier diet harder. High production and consumption of red and processed meat, and low consumption of wholegrains, vegetables, fruit and beans, plays a role in increased cancer risk and the risk of other diseases such as diabetes. This misalignment also contributes to unhealthy natural environments, as diet-related greenhouse gas emissions are significant contributors to global warming. Most of these are related to production of animal-based foods. This is why prevention is the only sustainable way forward – with resilient populations and food systems working together for public health.

Prevention the sustainable way forward

We believe that prevention must be prioritised and is the only sustainable way forward. We also need to better explain:

1. The science around cancer risk and diets, weight, breastfeeding, physical activity, and alcohol – as summarised in our Cancer Prevention Recommendations.
2. Which policies should be prioritised to shape healthier environments that minimise these cancer risks for populations.
3. How cancer prevention policy can have positive cascading effects for our health, but also for our health systems, our societies and our shared natural environment.

Cancer prevention policies can have ripple effect

We also know that cancer prevention policies can touch on and improve other areas beyond health. For example, diets high in red and processed meat increase people’s risk of colorectal cancer, and that healthier diets made up of more wholegrains, fruit and vegetables can protect people from the same type of cancer. This is why our Cancer Prevention Recommendations say people should limit red and processed meat, and eat a diet rich in wholegrains, vegetables, fruit and beansAt the same time, if our food systems produced less red and processed meat, and animal- food in general, and instead moved towards producing plant-based foods, this would have a significant impact in lowering diet-related CO2 emissions. Policymakers need to make sense of these connections, and our guidance shows what they need to do to promote such positive cycles – or co-benefits.

Why we created the Blueprint

Our well-established Cancer Prevention Recommendations cover 10 ways in which individuals can minimise their risk of preventable cancers. A growing body of evidence is showing that adherence to these Recommendations is associated with lower risk of developing cancer and other NCDs, but also lower risk of dying from cancer.

However, the Recommendations have not – until now – been presented alongside population-level policy advice. We need to promote an integrated approach to preventing cancer, otherwise policymakers may risk formulating repetitive but disconnected policy strategies across these areas that do not speak to or build on each other. For example, marketing restrictions can be a useful tool to encourage healthy diets but are also relevant for promoting breastfeeding and limiting alcohol consumption. Even though the targeted products are different, there are lessons to be learned from policy efforts across different cancer risk factors.

By joining the dots in these different areas, we can create greater awareness of how different policy approaches can contribute to cancer prevention. Our new blueprint makes a compelling case for action, especially for prevention to be included in national cancer plans. The blueprint also reinforces the need for a whole-of-government approach that puts public health goals before commercial interests.

What’s inside the Blueprint?

The Blueprint is accompanied by factsheets on specific cancer risk factors.

Our policy blueprint makes the case for population-level policy action and focuses on 5 factors: diet, weight, breastfeeding, physical activity and alcohol – in line with our Cancer Prevention Recommendations. We also look at how these factors can support people living with and beyond cancer

Our blueprint is an essential, evidence-based guide for policymakers and advocates, pulling together tools and resources to provide a comprehensive resource on cancer prevention. It pulls together existing tools and resources to support efforts on cancer prevention, including key guidance for World Health Organization, but also our existing NOURISHING nutrition and MOVING physical activity policy frameworks. All this information is distilled in a package of resources:

• An outline of 8 policy areas – including marketing restrictions, fiscal and legal, procurement, planning and incentives in communities– and how they apply to diet, weight, breastfeeding and physical activity.
• 10 factsheets with in-depth technical detail on how to roll out each Recommendation at population level.
• An exploration of the co-benefits of cancer prevention policy: addressing health inequities; meeting climate and sustainability targets; addressing commercial determinants of health; and fulfilling human rights.
• 7 strategies to help policymakers take action.

The goal of these resources is to strengthen understanding of how environment shapes cancer risk, and what policymakers can do about it.

How it was developed

To develop these resources, we built on our policy work, we reviewed existing key policy documents, and asked experts in the science and policy of cancer prevention, as well as lawyers, advocates for non-communicable disease prevention or breastfeeding what is most important in their respective areas. We then brought all the main elements together.

What’s next?

The Policy blueprint for cancer prevention will now be a centrepiece of our conversations with policymakers going forward – from Member States at the World Health Organization to the UN High-Level Meeting on Non-communicable diseases.

We invite you all to get involved: download the blueprint, share it, and use it in your work.

> Download it now

> Download our factsheets and other policy tools in our resource library

> To give us feedback and share how you want to use the blueprint, write to policy@wcrf.org

At World Cancer Research Fund, our mission is to live in a world where no one dies from a preventable cancer, so of course they’re all designed to help you live a healthier, happier cancer free life!

25 things for 2025

1. Drink more water!

The human body comprises around 60% water, so drinking enough water will help improve your physical performance and increase your energy levels.

2. Eat more beans, legumes and pulses

They’re a great source of protein, iron and fibre, they’re much cheaper than meat and good for the climate.

A new study funded by World Cancer Research Fund has found that activity throughout the day, with peaks in the morning and late afternoon, correlated with an 11% reduced risk of developing colorectal (also known as bowel) cancer, compared with other patterns of exercise studied.

This study used accelerometer data (which measures movement) to analyse daily activity. It used a statistical method that examines all of the data and finds common patterns, and how those patterns might be related to the risk of colorectal cancer.

Researchers from Regensburg University utilised data from the UK Biobank, which had contacted 86,252 randomly selected individuals (56% of them women), asking them to wear accelerometers to track their movement over 1 week and following them for 5 years to monitor the development of colorectal cancer. When studying the data, researchers identified a 2-peak pattern of daily physical activity associated with reduced colorectal cancer risk.

The researchers identified 4 different patterns of physical activity throughout the day:

1. Continuous day-long activity
2. Activity later in the day
3. Early and late-day activity
4. Activity in the middle of the day and during the night

The 3rd pattern, where people were active both in the early and late parts of the day, was associated with an 11% lower risk of colorectal cancer, compared with 6% for day-long activity and no change for middle of the day and the night. Data from activity later in the day only was inconclusive. These findings held true even when considering factors such as smoking, shift work and other variables that could affect a person’s cancer risk.

Impact on sedentary lifestyles

In addition, the researchers found that a day-long activity pattern most effectively reduced colorectal cancer risk among individuals who were more sedentary. This may be because the effect of physical activity becomes more obvious when contrasted with a previously more inactive lifestyle, meaning that those who are fit and healthy are already at a reduced level of cancer risk. These findings show how beneficial physical activity can be, especially in those who are more sedentary.

Dr Helen Croker, Assistant Director of Research and Policy at World Cancer Research Fund, said:

“Being physically active is one of our Cancer Prevention Recommendations, and we know that this cuts cancer risk. These intriguing new findings offer potential for developing more specific recommendations, including patterns and timing of physical activity, for reducing cancer risk. This shows the vital importance of World Cancer Research Fund continuing to support research that expands our knowledge to inform cancer prevention going forwards.”

Prof Michael Leitzmann, Chair of the Department of Epidemiology and Preventive Medicine at the University of Regensburg, Germany, who was the lead investigator in the study, said:

“Our study highlights that not only is physical activity important for reducing colorectal cancer risk, but the timing of peak activity throughout the day could play a crucial role. By identifying specific times – early morning and late day – when physical activity is most beneficial, our findings open new avenues for targeted prevention strategies. If confirmed by future research, this could provide a simple yet impactful way for individuals to further reduce their cancer risk through the timing of their exercise.”

Read the paper

Stein, M.J., Baurecht, H., Bohmann, P. et al. Diurnal timing of physical activity and risk of colorectal cancer in the UK Biobank. BMC Med 22, 399 (2024).

More on this grant

The combined impact of physical activity, sedentary behaviour and cardiometabolic comorbidities on cancer risk and survival among cancer survivors

About the UK Biobank

The UK Biobank is a large, population-based prospective study, established to allow detailed investigations of the genetic and non-genetic determinants of the diseases of middle and old age. It has 500,000 UK participants between the ages of 40–69.

About the University of Regensburg

The University of Regensburg is a nationally and internationally renowned comprehensive university with an excellent research spectrum, an attractive range of courses and a high sense of social responsibility. The UR stands for diversity, openness to the world and shaping the future. Its research strength is demonstrated by 6 Collaborative Research Centers funded by the German Research Foundation (DFG) and 9 grants from the European Research Council.

In 2017, the Institute for East and Southeast European Studies (IOS), an affiliated institute of the UR, was the first institution in Regensburg to be accepted into the renowned Leibniz Association, followed in 2022 by the Leibniz Institute for Immunotherapy, which emerged from the Regensburg Center for Interventional Immunology. In May 2024, the Regensburg Center for Ultrafast Nanoscopy opened at the university, where the ultra-fast quantum movements of atoms and molecules are researched using innovative, high-resolution slow-motion cameras. In spring 2022, the Science Council recommended funding for the Center for Immunomedicine in Transplantation and Oncology at the UR, a center for basic research in immunomedicine.