Most members of Gen Z, born between 1997 and 2012, can expect to live into their early-to-mid 80s based on current actuarial data. U.S. life expectancy hit a record high of 79 years in 2024, and because Gen Z will benefit from decades of additional medical advances, their projected lifespans trend slightly higher. But that number isn’t guaranteed. Rising rates of obesity, depression, and other chronic conditions among young adults are creating real headwinds that could stall or even reverse those gains.
What the Numbers Say Right Now
Life expectancy is a moving target. The figure you see reported (79 years for the U.S. in 2024) represents a “period” estimate, a snapshot of mortality rates across all ages in a single year. It doesn’t account for future improvements in medicine, public health, or technology that someone born today will experience over their lifetime. For that reason, actuarial projections for Gen Z typically land a few years higher, in the range of 82 to 85 for those born around 2000, assuming continued but modest progress against major diseases.
Sex makes a meaningful difference. In 2024, U.S. women had a life expectancy at birth of 81.4 years compared to 76.5 for men. That roughly five-year gap has persisted for decades and shows up in every wealthy country, not just the United States.
The U.S. Falls Behind Other Countries
Where you live matters almost as much as when you were born. A Gen Z member in Switzerland or Japan is starting from a significantly higher baseline than one in the United States. In 2024, life expectancy at birth was 84.2 years in Switzerland, 84.1 in Japan, and just 79.0 in the U.S. The average across comparable high-income nations was 82.7, putting Americans nearly four years behind.
That gap is especially stark for men. American men trail their peers in comparable countries by about 5.3% in life expectancy at birth. For women, the gap is smaller but still significant at 4.1%. These differences stem largely from higher rates of gun violence, drug overdoses, obesity, and weaker access to preventive healthcare in the U.S. compared to peer nations. A Gen Z American and a Gen Z Japanese person face genuinely different odds.
Chronic Disease Is Starting Earlier
The biggest threat to Gen Z longevity isn’t a single dramatic event. It’s the slow accumulation of chronic health problems at younger ages than previous generations experienced. CDC data tracking young adults (ages 18 to 34) from 2013 to 2023 found that the share with at least one chronic condition climbed from 52.5% to 59.5%. More than one in four young adults (27.1%) now has multiple chronic conditions, up from 21.8% a decade ago.
The two conditions driving most of that increase are obesity and depression. Among young adults in 2023, 27.3% had obesity (up from 22.1% in 2013) and 25.0% had depression (up from 16.4%). High cholesterol affected 16.3%. When researchers excluded obesity and depression from their analysis, the overall rise in chronic disease among young adults essentially disappeared, confirming that these two conditions account for nearly all the worsening trend.
This matters for longevity because obesity in your 20s dramatically raises your risk of heart disease, type 2 diabetes, and certain cancers in your 40s and 50s. Depression, beyond its direct toll, is linked to higher rates of substance use, cardiovascular disease, and suicide. The concern among public health researchers is straightforward: as this cohort of young adults ages, these conditions will compound, potentially erasing the life expectancy gains that medical advances would otherwise deliver.
Mental Health and Deaths of Despair
The U.S. suicide rate has risen nearly 40% since 2000 after falling for decades. Among people under 25, the surge in depression during the 2010s was so large it could explain nearly all the increase in suicide deaths in that age group. For Gen Z specifically, death rates in the 15-to-24 age range did improve recently, dropping 12.9% from 2023 to 2024 (from 76.8 to 66.9 deaths per 100,000). But the longer trend line remains troubling.
The risk isn’t evenly distributed. Men die by suicide at four times the rate of women. LGBTQ youth face elevated risk driven partly by higher rates of bullying. And while suicide has historically been most common among white and Native American populations, the last several years have seen a sharp relative increase among racial and ethnic minorities and among women. Access to mental health care remains a bottleneck. Even when people have insurance, getting timely treatment is often difficult in practice.
Suicide replaced COVID-19 as the tenth leading cause of death in the U.S. in 2024. For younger age groups, it ranks much higher. Whether Gen Z’s mental health trajectory improves or worsens over the coming decades will meaningfully shape this generation’s average lifespan.
Climate Change Adds a New Variable
No previous generation has had to factor in climate change as a lifelong health risk the way Gen Z does. Research published in Nature projects that under current climate policies, which put the world on track for roughly 2.7°C of warming by 2100, the fraction of people facing unprecedented lifetime exposure to heatwaves, crop failures, floods, droughts, wildfires, and tropical cyclones will at least double compared to people born in 1960.
Even under the most optimistic scenario (limiting warming to 1.5°C), 52% of people born in 2020 will experience unprecedented heatwave exposure over their lifetimes. Under a 3.5°C pathway, that rises to 92%. The 2020 birth cohort is projected to live through roughly 11 major heatwaves under the best-case scenario, 18 under moderate warming, and 26 under high warming.
These aren’t abstract statistics. Extreme heat kills directly through heatstroke, but it also worsens heart disease, kidney disease, and respiratory conditions. Crop failures affect nutrition. Wildfires degrade air quality for millions. The cumulative health burden of these exposures over a full lifetime is something demographers are only beginning to model, and it introduces genuine uncertainty into any projection of how long Gen Z will live.
Income Will Shape Individual Outcomes
Averages obscure enormous variation. In the U.S., the gap in life expectancy between the wealthiest and poorest communities spans roughly 10 to 15 years depending on the study and geography. For Gen Z, this gap could widen further. Wealthier individuals have better access to preventive care, healthier food environments, lower exposure to pollution, and more resources to manage chronic conditions early. Lower-income Gen Z members are more likely to live in areas with limited healthcare infrastructure, higher rates of gun violence, and greater exposure to environmental hazards.
So while a college-educated Gen Z professional with good health insurance might reasonably expect to live into their late 80s, someone in a low-income rural or urban community faces odds that look very different. The “average” life expectancy for the generation is real, but no individual lives an average life.
A Realistic Range
Pulling these threads together: Gen Z in the U.S. is likely looking at an average life expectancy somewhere in the low-to-mid 80s, assuming continued medical progress and no catastrophic disruptions. That’s a few years longer than today’s 79-year figure, reflecting improvements in cancer treatment, cardiovascular care, and infectious disease management that will accumulate over their lifetimes. Gen Z members in Japan, Switzerland, and similar countries start from a higher baseline and could average into the mid-to-upper 80s.
The downside risks are real, though. If obesity and depression trends continue their current trajectory, if climate-related health burdens grow as projected, and if mental health care doesn’t improve meaningfully, Gen Z could be the first modern generation in the U.S. to see life expectancy plateau rather than climb. The optimistic and pessimistic scenarios are separated by roughly five to seven years, and which one plays out depends heavily on public health decisions being made right now.