Young people are underrepresented in medical trials, prompting warnings that future treatments could be less safe or effective for younger generations, The Guardian has revealed.
Gen Z – those born between the late 1990s and the early 2000s – make up 8 per cent of England’s population but just 4.4 per cent of participants in medical research, analysis of National Institute of Health and Care Research (NIHR) data reveals.
Experts say this imbalance means new treatments and interventions are often tested primarily on older adults, which may not accurately reflect how they work in younger people.
Almost half – 45 per cent – of those aged 24 or under have a long-term physical or mental health condition including diabetes, obesity, asthma, autism, learning difficulties, epilepsy, eating disorders and other mental health conditions.
Kirsty Blenkins, deputy chief executive of the Association for Young People’s Health, said adults aged 24 and under faced “a distinct set of health challenges” that were often “shaped by major life transitions, social pressures and inequalities” that impacted their physical and mental wellbeing.
She added: “Treatments and interventions may be designed and tested primarily on older adults, which means they may not always be safe, effective, or appropriate for younger populations.
“This can lead to poorer health outcomes, delayed diagnosis, and reduced trust or engagement with healthcare systems.”
Between April 2021 and March 2024, 32,879 adults aged 18 to 24 took part in 5,042 studies backed by the NIHR research delivery network – an average of seven young people per study.
In contrast, people aged 85 or older make up only 2 per cent of the population but accounted for 32,031 participants during the same period, representing 4.2 per cent of the total.
Blenkins said factors behind low participation include limited awareness of research opportunities, lack of targeted recruitment, concerns about confidentiality, and a research culture that is rarely designed with or for young adults.
“Increasing representation requires a more inclusive research design, involving young people from the start, making participation accessible and relevant, and embedding youth engagement as standard practice across the research system,” she said.
Dr Esther Mukuka, NIHR’s director for research inclusion, said: “Young people often don’t realise that they can and should take part in health research. When people think of research, they often picture experimental treatments for serious illnesses like cancer, but it’s so much more than that.
“Research shapes how we manage everyday conditions like diabetes, and how mental health support is offered on the NHS. Gen Z is faced with their own unique health challenges.
“They also engage with the healthcare system differently.
“If this group does not participate in research, the treatments and services developed as a result will not reflect their needs.
“Scientific discovery is moving further and faster than ever. And it’s clear that the treatments of tomorrow will be very different from what we understand today.
“Health and care systems need to evolve with society, so it’s crucial that young people take part in research now.
“Without their input, future treatments won’t be as representative or effective as they need to be.”
An NIHR campaign aims to encourage more people to take part in health and care research through a UK-wide volunteer registry that matches people with studies aligned to their health concerns and interests.
Anyone can take part in research, whether they have a health condition or not.
Some studies seek to include people without the condition so researchers can compare them to those who have it.
“Getting involved can be super simple, including filling out a quick survey or giving a saliva sample,” said Mukuka.
“And if you don’t have a health condition, consider taking part anyway. You can still help shape the NHS of tomorrow.
“Think of it as investing in the kind of care you’d want for yourself, your friends, and your family.”
Dr Wendy Macdowall, from the London School of Hygiene & Tropical Medicine, said women and ethnic minorities were also underrepresented.
“To reduce inequities, knowing whether interventions ‘work’ is not enough. We also need to know whether particular groups of people experience them differently.
“Understanding how different groups experience interventions is key in order that practitioners can make informed decisions about their adoption in specific sub-groups and to ensure that interventions don’t inadvertently produce, or exacerbate, inequities.”
