Recently born generations may spend more years in poor health

Millennials and gen Z are more likely to live with obesity and report mental health difficulties earlier in their lives than the baby boomers and generation X, according to a new review of studies comparing UK birth cohorts. 

The trend, described by researchers as a ‘generational health drift’, suggests that more recently born generations may spend more years living in ill health than their earlier born counterparts. 

What we asked you 

The review by researchers from University College London, King’s College London and University of Oxford examined changes in the physical and mental health of multiple generations of people. This included baby boomers born in 1946 and 1958, members of generation X born in 1970, millennials born in 1989-90 (that’s you!) and gen Z born in 2000-02. 

What the researchers found 

Drawing on evidence from 51 studies published up to June 2024, the research revealed: 

• Rates of childhood overweight and obesity were highest among gen Z. 
• Diabetes in midlife (age 44-48) almost doubled from 3.1% among the baby boomers to 5.9% in generation X. 
• Gen Z exhibited higher levels of mental ill-health in adolescence compared to earlier born groups. 
• Levels of life satisfaction were lower among millennials than generation X. 

The researchers said the findings have implications for investment needed to care for increasing numbers living with long-term health conditions. Health has worsened despite declines in smoking, increasing educational attainment, and improvements in material circumstances early in life. 

Why this research matters 

By 2050, a quarter of the British population will be aged 65 or over which will increase demands on health and social care systems and the economy. As such, it is important that people born more recently live not only longer but also in good health to meet the challenges of population aging. 

The findings raise important questions about the apparent worsening of health, which the authors suggest is most plausibly driven by a genuine increase in poor health. Increasing survival rates are unlikely to explain the trend, given that generational differences are evident from early life through midlife. Similarly, the consistency of findings across both self-reported and objectively measured health outcomes makes it unlikely that changes in measurement alone underlie the observed pattern. 

Lead author, Laura Gimeno (UCL Centre for Longitudinal Studies) said:

“We’re seeing the consequences of preventable social and environmental exposures that have shaped population health over time and across generations.” 

“The generational health drift has serious implications for policy, planning, and the funding allocations needed to be able to support a greater number of people living with long-term health conditions.” 

In the press 

The Independent – Young people in UK more sick than previous generations 

The Mirror – Younger generations get sick earlier due to obesity and mental illness, study shows 

ITVX – Young people in UK more sick than previous generations 

Read the full research report 

‘The Generational Health Drift: A Systematic Review of Evidence from the British Birth Cohort Studies,’ by Laura Gimeno, Dario Moreno-Agostino, Martin Danka, Yiling Guo, Alice Goisis, Jennifer B Dowd and George B Ploubidis was published in Population Studies in May 2026.