Do people really look younger than they used to?

Chronological versus biological age

Science has come to understand different types of aging. What we call age is simply the number of years since birth, or chronological age. At the cellular level, biological aging happens at different rates for different people, and explains why some seem to age more quickly (or slowly).

Each part of the human body experiences aging differently

With global average life expectancy cresting at 73 years, understanding how the body ages is imperative to effective medical treatment and maintaining a desired quality of life. This 13-minute video dives into how the body and its organs age "from head to toe."

Multiple new research paths may lead to slowing (or even reversing) aging

Aging has always been inevitable, but fasting, epigenetic reprogramming, and parabiosis seem to help people stay young. By studying centenarians, memory, and even the humble roundworm, scientists are looking for the genetic basis to live not just a long life, but a healthy one.

The quest to find natural ways to extend lifespan

Tales of searching for the Fountain of Youth persist. Our modern-day version is marked by promises of pharmaceutical miracles and a proliferation of viral "biohacking" routines. One doctor’s quest to unlock the keys to longevity stimulated much of this renewed fervor, though his ideas are often taken out of context.

The formula behind super agers—those possessing health and cognitive skills of people decades younger

A study of about 1,400 super agers did not identify any underlying genetic mechanism for longevity. While researchers instead emphasized that sustainable habits involving positive social connections, sleep, mood, diet, exercise, and personal fulfillment help reduce long-term risks, there is no one-size-fits-all formula for everyone.

DNA damage and chemical stress causes cellular aging

While outward signs of aging, like gray hair and wrinkles, are easy to spot, aging changes at the cellular level are less obvious. The decline within cells stems from numerous sources, including DNA damage, oxidative stress, and accumulated waste.

Doctors use three key physical markers to determine biological aging

The length of the ends of chromosomes (known as "telomeres"), the gradual change in collections of DNA molecules called "methyl groups", and the secretion of inflammatory proteins are all used as indicators of biological age.

Aging is a complex biological process affecting our cells, tissues, and organs.

See how faces on magazine covers have changed over time

This piece examined an archive of Time magazine containing 3,389 issues ranging from 1923 to 2014, focusing on 327,322 faces from the archive. Read what the researchers learned.

Can humans delay or reverse old age?

We're not sure yet. Researchers at the University of California San Francisco are studying why some conditions and behaviors, such as low-oxygen environments and exercise, benefit the aging process, hoping to reveal potential health applications. Some of this research focuses on klotho, a naturally occurring age-regulating hormone named after the Greek Fate Clotho. Animal studies on klotho brain injections found subjects had improved memory recall and age-related degeneration resistance.

External factors, not aging itself, lead to sleep loss in older adults

Though it is often believed that people need less sleep as they age, the recommended sleep guidelines for all adult age groups are almost identical. However, factors such as medication use, lack of physical activity, and loneliness can lead to sleep problems, and thereby lead older people to believe that they actually need less sleep than they do.

Most self-reported claims of exceptional longevity are exaggerated, but read how demographers verify age claims and why some of the original blue zone demographers say blue zone regions are real and worth studying.

Roughly 10% of the world's population is older than 65 (2023 data)

With recent advances in medicine, sanitation, and nutrition, expected lifespans have rapidly risen around the globe—resulting in a rapidly aging global population. The worldwide distribution has seen a nearly 600% jump in the population of people aged 65 and older.

Aging explained with Dr. Nick Golinvaux

Aging is more than wrinkles and gray hair—it’s a gradual decline in cellular function. Over time, DNA damage, telomere shortening, and mitochondrial inefficiency contribute to weaker bones, slower memory, and reduced vitality. While aging is inevitable, regular exercise, quality sleep, and stress management maintain health and extend one’s years.

Perceived isolation ages you

Mounting evidence suggests that socialization is a vital component of maintaining good health. Research published in 2024 from Mayo Clinic researchers analyzed the social lives of more than 280,000 adults and concluded that individuals that weren't likely to participate in extracurricular social activities and get-togethers were more likely to have a biological age older than their actual age—meaning that you may be 60 but health indicators would suggest you're older.

Super-agers: seniors 80 and above with the memory ability of people in their 50s

Studies show the number one indicator of whether someone is a "super-ager" is not diet or genetics, but the extent of their social relationships. Moreover, scans reveal noticeable physical differences in certain parts of the brain in patients with extensive social networks.

Gen Z is drinking less alcohol than older generations.

Three ways the US population will change over the next decade

This article lists the top three ways the US population will change over the next decade. Using population data from the US Census Bureau and the UN Population Division, the piece explores what America might look like 10 years from now, which...

Visualizing cause of death over time in America

As people age, their life expectancy decreases, but the timing and speed of this decline have evolved over the years. Check out this chart which shows the shift in various causes of death of Americans over the last few decades. Data from the...

Environment and genetics explain why animals have widely different lifespans

Both environmental conditions and genetic factors shape how long various animals live. For some creatures, colder conditions allow for less energy use and slower aging. Larger animals have fewer predators. While humans don't live the longest, we are a rare species that successfully lengthened its average lifespan over time.

Strength training appears to make for a healthier, youthful-looking brain.

Cancer rates are on the rise among GenXers and Millennials

Cancer rates are rising among Gen X and Millennials, with more cancer diagnoses being made in their 30s and 40s than previous generations. Factors such as prenatal exposures, environmental toxins, and lifestyle choices may contribute to this trend. Memorial Sloan Kettering Cancer Center's experts discuss these issues, exploring how these insights could reshape cancer risk understanding.

Individuals typically spend less time with others as they get older

At younger ages, we spend much of our time with parents, siblings, and friends. Eventually, our lifestyle changes to include work, a spouse, and children of our own. In later life, children often move out, and spouses unfortunately pass away, leading to more time spent alone.

Circadian rhythms shift as we age—making older adults want to go to bed earlier

Throughout our lives our internal biological clocks shift. Early-to-rise toddlers become hard-to-wake teens and eventually early-to-sleep seniors. Circadian rhythm fluctuations throughout our life cycle explain some of these changes.

Doctors shift focus from extending lifespan to lengthening health span

As scientific advances extend the average human lifespan, many are turning their attention toward extending "health span." Health span refers to the number of years one is active and disease-free. The ultimate goal is to extend one’s health span to match one’s lifespan.

Girls are hitting puberty earlier than ever before

Around the world, there has been a spike in children—especially girls—experiencing early puberty and doctors are seeking to understand why. The rise has been particularly strong post-2020. Early-maturing girls are at a higher risk for developing...

Why young women experience the most workplace ageism

While one might assume that older women face the most unfair treatment due to age in the workplace, some research from McKinsey & Co. suggests otherwise. The consulting firm found that while ageism impacts older women and men at similar rates, women in their 20s and 30s report much higher instances of ageism than both older women and their young, male colleagues. Learn more from the research here.

What happened to thousands of teens from the 1990s?

Scientists followed thousands of teenagers from 1997 into their 30s, cataloging their adverse experiences along the way via nearly three decades of interviews. Teens who grew up dealing with poverty, uninvolved parents, and other childhood stressors and traumas racked up an ACE score. These adverse childhood experiences have lifelong impacts on one's health, relationships, financial security, and "pretty much everything else," making them more likely to suffer premature death.

Aging results from the cumulative breakdown of cellular and tissue processes

A cumulative breakdown of cellular and tissue processes combines to result in decreased organ function, disrupting the systems driving normal human physiology. This five-minute video provides a primer on the subject, complete with a discussion of risk factors, cellular changes, and potential future treatments in the fight against aging.

Global life expectancy has more than doubled since the 1850s

The human species experienced a dramatic increase in expected lifespan over the past 150 years. Antibiotics, improved sanitation, and better worldwide food distribution are a few factors contributing to this rapid transformation. Use this interactive resource to explore longevity gains over time and compare these improvements across the globe.

Americans are retiring later than they used to

A Gallup poll from 2022 found that the percentage of adults between the ages of 55 and 74 who are retired is declining.

'Old people' smell is real—it's a chemical buildup when fatty acids on the skin oxidize

The chemical composition of body odor seems to change with age. Later in life, we harbor higher concentrations of a chemical compound called 2-nonenal that forms when omega-7 fatty acids on the skin oxidize, and the skin's natural antioxidant defenses weaken. Commonly called "nonenal", it's the smell widely associated with aging, and it's often described as a grassy or greasy odor.

Is human evolution speeding up or slowing down?

In the past 3,000 years, many populations have evolved genetic adaptations to their local environments. People in Siberia and the high arctic are uniquely adapted to survive extreme cold. The Bajau people can dive 70 meters and stay underwater for almost 15 minutes. So what are other recent changes? And will our technological innovations impact our evolution?

How aging degrades neural functioning in the brain over time

Aging affects the brain perhaps more than any other organ in the body. Throughout life, the brain experiences radical shifts in the number of neurons, synaptic connections between neurons, and hormone levels that regulate our mood and processing.

See preferred supplements across different countries in 2025, by generation

Millennials and Gen Z typically took more supplements than other age groups across vitamins, proteins, minerals, and herbal supplements, according to 2025 data from a Global Consumer Insights Survey conducted in 55 countries. Roughly two-thirds of Gen Z respondents stated they'd taken vitamins in the past 12 months. (Some users may experience a paywall.)

Explore how the most commonly used words in the English language have changed from the 1950s to 2023.

Explore why Americans are drinking less alcohol

US alcohol consumption fell 5% in 2025, with beer and wine leading the decline. Economists point to tighter budgets and less face-to-face socializing overall, while younger Americans are increasingly choosing not to drink.

One biologist is leading the blue zone criticisms—both questioning the original recordkeeping for these purported longevity-prone locations and pointing to recent research showing declining numbers of healthy seniors in several official blue zone regions.

Your brain appears to age in five distinct stages, with the pattern of connections inside your brain shifting, on average, around ages 9, 32, 66, and 83.

Moving your body every day is key to longevity

In an era of biohacking, where millionaires subject themselves to draconian routines and tests to de-age themselves, one study suggests a super simple key predictor of mortality: more than any other trait, how much subjects moved determined how long they'd live. Movement mattered even more than age in predicting overall life longevity. Researchers suggest this means we should all simply get outside a bit more. Read more about the study here.

The history of the gene: an interactive timeline

Humans didn’t need modern technology to figure out that kids tend to look like their parents. But what did humans believe about genetics before we knew about DNA or cells in general? Explore this interactive timeline to see how philosophers and scientists throughout the ages tried to explain how traits are passed from generation to generation.

According to the special theory of relativity, the faster objects move through space, the less they move through time, and therefore age more slowly.

The Dog Aging Project uses information from over 50,000 dogs to explore longevity

The study gathers health, lifestyle, and genetic data to understand what helps dogs live longer, healthier lives. Findings could also provide human health insights due to our shared surroundings and biology.

Why are kids increasingly diagnosed with myopia?

According to the World Health Organization, 40% of the world will have myopia—nearsightedness—by 2030. This NPR podcast episode details why people are being diagnosed with myopia at increasingly younger ages. Early onset myopia can lead to...

Data visualizations showing population growth around the world

This page presents data, charts, and analysis on changes in population growth around the world. Over the last few centuries, the human population has gone through an extraordinary change. In 1800, there were 1 billion people; today, there are more...

Where you are located in a gravitational field affects how quickly you age

The closer something is to the center of a massive object, the greater the strength of the massive object's gravitational field as a result of space-time being depressed more severely. Time passes more slowly the deeper an object is in this gravitational depression, meaning objects in the universe naturally seek to age more slowly.

Ten writers and thinkers on what growing older actually requires of us

The Marginalian's Maria Popova curates a collection arguing our culture has learned to dread aging while forgetting it is a privilege, and that the antidote is sustaining passions strong enough to keep us from turning inward. Voices include Simone de Beauvoir, Joan Didion, Pablo Casals, and Kahlil Gibran.

Read a study documenting how 'old people' smell increases with age

Analysis of body odors from individuals aged 26 to 75 confirmed that 2-nonenal, an unsaturated aldehyde with an unpleasant, greasy, and grassy odor, was detected only in subjects aged 40 and older.

Genetic engineering will change everything forever

Designer babies, the end of diseases, genetically modified humans that never age. Outrageous things that used to be science fiction are suddenly becoming reality. As scientists increasingly understand how specific genes cause disease, the possibility of engineering our genes to not only "fix" problems but enhance our natural ability grows.

Three examples of how humans are still evolving

For much of nature, natural selection and "survival of the fittest" still play a dominant role; only the strongest can survive in the wild. As little as a few hundred years ago, the same was true for humans, but what about now?