Child mortality rates since ancient Rome

Under-5 child mortality has been cut in half since 2000, UNICEF reports

The United Nations Children's Fund works globally to protect children's rights and well-being. Its 2024 report on child mortality reveals that under-5 deaths have halved since 2000. The report includes interactive data visualizations that can be sorted by year or topic.

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.

Measuring the chance a Roman emperor would die violently

The odds of survival for a Roman emperor were like playing Russian roulette with a six-chambered revolver and four bullets, according to this scientific journal article. Of the 69 rulers of the unified Roman Empire between 14 CE and 395 CE, 43 suffered a violent death. This journal article examines Roman emperors' time-to-violent death using statistical tools of survival data analysis.

The disparity in life expectancy between wealthy and impoverished nations has notably narrowed

In 1950, people in Norway lived to age 72, on average, while those in Mali lived to just 26. By 2015, the countries with the worst conditions had made such significant progress that the global average life expectancy had surpassed the rate of any nation in 1950.

Explore US public health data

This resource tracks key US health metrics, including mortality causes, child survival rates, and life expectancy comparisons, to inform future health improvements, with regularly updated global estimates.

Mortality tables help determine the probability of death for specific populations

A mortality table is a diagram that helps predict a specific population’s likelihood of death within a particular time period. Life insurance companies often use them to help figure out pricing for their insurance products. They’re sometimes known as actuarial tables or life tables.

Diphtheria was once a leading childhood killer before antibiotics and vaccines

In 18th- and 19th-century outbreaks, some New England families lost as many as eight children to diphtheria, and fatality rates in hospitals often topped 60%. The invention of antitoxins, penicillin, and vaccines dramatically reduced deaths.

Obesity rates have more than doubled worldwide since 1990

In the US alone, the percentage of the population meeting the clinical standard of obesity rose from less than 20% to more than 40% over the past three decades. This rise has been matched by many countries across the globe, from industrialized to developing nations.

US cancer mortality rates have been falling for 25 years

The American Cancer Society's "Cancer Facts & Figures 2025" report provides comprehensive statistics on cancer incidence, mortality, and survival rates in the United States. Cancer rates in the US continued a long-running downward trend, driven primarily by a steep drop in lung cancers (mostly from a decrease in habitual smoking) and better preventative monitoring. This site leads to incredibly in-depth reports and slides on the current state of the fight against cancer.

France once had a reproduction czar to help midwives deliver babies

Much ado is made about falling marriage and birth rates worldwide, and how they might affect tax bases, retirement funds, and social standing. But this isn’t the first time marriage, and subsequently reproduction, have fallen out of favor. Some countries have resorted to drastic measures to restore the tarnished state of these hallowed institutions.

Play 17th-century death roulette

Before modern science and medicine, death was much harder to escape. Using real mortality records from London's Dreadful Visitation–a collection of all the Bills of Mortality from 1665–this interactive game gives you an idea of what may have possibly killed you during the Great Plague. Grow your appreciation for life today as you stumble upon causes of death like “livergrown” and “drowned at St. Katharine’s by the Tower”.

The US trails behind other developed countries in reducing its stillbirth rates and may learn from Australia

Australia is in the vanguard of efforts to bring down stillbirth numbers with a national stillbirth plan integrated into its healthcare system, supported by clinicians, nurses, midwives, and politicians. Its work also includes a public awareness campaign, more regular fetal monitoring and follow-up for potential interventions, and more maternal advice about care and safety during pregnancy.

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...

Analysis finds dementia was rare in ancient Greece

Ancient medical texts seldom mention severe cognitive decline, suggesting that such conditions were uncommon. This scarcity is attributed to factors like shorter lifespans and active lifestyles, implying that modern environmental and lifestyle changes—along with longer life expectancy—contribute to the current prevalence of dementia.

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.

Death taxes have helped fund wars since the 1860s

Death taxes date back to 700 BCE and were used in Ancient Rome and Ancient Egypt. In the US, they've been used to finance wars since the Civil War, and have been levied on both the estate and beneficiary. The estate tax created during WWI to help finance war efforts is still in effect today.

Why do humans have such long childhoods?

Humans have over twice as long childhoods than other animals with similar lifespans like whales and elephants. A human child can grow for nearly 20 years before they become a reproducing adult. Researchers believe there's a connection between long childhoods and human's unusually large brain size, though the science is not totally clear. Dive into what scientists know here.

In the original 2004 blue zones study, which sought to verify the ages of long-lived, healthy populations in Sardinia, Italy, researchers hypothesized that inbreeding in these isolated communities may have helped promote their longevity. (Paywall may apply.)

The concept of life insurance likely originated in ancient Rome around the year 100 BCE

However, life insurance policies didn’t reach the Americas until 1759, when life insurance started being used to protect the families of Protestant ministers when said ministers died. This timeline of life insurance’s early history—and how it has evolved since then—provides more details.

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...

Heat-related deaths may have climbed by more than 50% over 20 years

Between 2000 and 2009 one study suggests annual heat deaths averaged around 2,670, but between 2010 and 2020 that figure was likely more than 4,000. Researchers studied 54 million death records from the contiguous US and created mathematical models to arrive at these figures, noting that a combination of aging populations and climate change drove that increase.

Ancient Egyptians developed the first pregnancy test—and scientists tested it in the 1960s

A papyrus from about 1350 B.C.E. discusses a test in which a woman would urinate on wheat and barley seeds over the course of several days. If the barley grows, she's having a male child; if the wheat grows, it's a female child; and if nothing grows, she's not pregnant. Scientists went on to test this theory in 1963 and found that about 70% of the time, the urine of pregnant women did promote growth whereas the urine of nonpregnant women didn't—perhaps due to estrogen levels in the urine.

As of 2022, scientists estimate that 117 billion people have been born on Earth

Although no demographic data exist for more than 99% of the time humans have existed, this value can be estimated by tracking approximate population sizes over different periods and the birth rates within those periods. In 2022, about 6.8% of humans that have ever been born were alive.

The measles vaccine has saved an estimated 94 million lives since its introduction

Measles killed an estimated 2.6 million people globally in 1980, after the development of a vaccine but before its widespread dissemination. By 2014, that figure had dropped to an estimated 73,000.

How global conditions have improved over 200 years

In an era of 24-hour news, it can feel as if the world is on a perpetual downward spiral. This set of visualizations zoom out, and show how global living conditions have improved in recent centuries. The percentage of people living in extreme...

See how populations across the world could change in the 21st century

This tool lets you model the populations of individual countries by adjusting key demographic inputs. See how changes in birth rates, mortality, and migration affect the size and structure of future populations.

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...

Each day, about 60 US pregnancies end in stillbirth

This online memorial for families who experienced the unexpected death of a fetus 20 weeks or older is the result of ProPublica reporters inviting 60 families to share their baby's name and answer some questions about their unfulfilled wishes for their children. About 21,000 babies are stillborn in the US annually. About the same number of children die in the US during their first year of life.

The ancient engineers inspiring modern building practices

Modern concrete structures need replacing every 50 to 100 years, so why are buildings by the Maya, ancient Rome, and ancient China still standing strong? This article details how scientists are looking into humanity's past for clues on how to craft long-lasting structures. Part of the problem is adopting old material recipes to hold up to modern demands.

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.

Children under 5 account for 76% of all malaria deaths in Africa

The main hypothesis for why the disease hits this age group the hardest is that children this young have still-developing immune systems. Pregnant women and people with HIV/AIDS are also at higher risk of severe infection.

Lung cancer advances are making a big difference

Lung cancer deaths are declining faster than new cases due to advances in treatment. The progress illustrates what is possible, even for a cancer that has long had a poor prognosis.

Studies estimating the number of years between human generations suggest there have been approximately 10,000 to 12,000 generations of humans.

Mummification involves drying a body to preserve it long-term

It was a common and respected practice in many ancient societies. The Egyptians perfected the ritual as part of their religious views of death, believing the dead needed to remain physically intact to reach the afterlife. Mummies were common also in ancient China, Mesoamerica, and the Canary Islands.

Eight British children have been born via mitochondrial replacement therapy

In July 2025, a decade after British lawmakers signed off on allowing three-parent IVF, scientists announced that eight healthy babies had already been born using this approach. The news was included in a pair of research articles published in a peer-reviewed journal that noted the oldest kids were already more than two years old, and that they were hitting developmental milestones as expected. (Some users may encounter a paywall.)

The ancient Greeks and Romans viewed comets and meteors as divine omens

Both considered the appearance of a comet or its fragments as a precursor to significant events, such as the birth of a notable figure or the death of a ruler. One observed in 44 BCE was believed to be a sign of the deification of Julius Caesar after his assassination.

Read the 1963 study testing out an ancient Egyptian pregnancy urine test

The study sought to test out the ancient Egyptian approach of having a woman urinate on barley and wheat seeds to ascertain pregnancy status. Surprisingly, the research concluded that pregnant women's urine did promote growth of cereal grains the majority of the time; nonpregnant women's urine did not. Unfortunately, the sex of the child could not be accurately predicted based on which crop grew.

Artificial wombs and preterm births: an overview

Scientists are working to create artificial wombs that would help preterm babies survive their early entry into the world. But how much help could this technology provide, and how much of a problem are preterm births? This article details some of...

Penicillin has saved an estimated 500 million lives since its creation

Since its introduction in the 1940s, penicillin and related antibiotics are estimated to have saved around 500 million lives worldwide—making it one of the most consequential medical breakthroughs in human history.

Why human brains were bigger 3,000 years ago

Our modern civilisation may be the most advanced to ever exist on Earth, but around 100 generations ago, our ancestors had brains that were larger than our own.

After a tragic 3 decades, F1 created better safety measures

The first three decades of Formula 1 saw 41 drivers die in competition; since 1980, only 11 have perished. The reduction is due, in large part, to better safety measures. This article highlights every safety improvement made by year since F1 started, and describes the accidents or deaths that led to the rule changes.

The strange endurance of consuming blood for health

Blood's importance to humanity is best summarized this way: without it, we die. This importance naturally begets assumptions about its medicinal properties, many of which appear accessible through drinking or eating the fluid connective tissue. This article details the history of blood drinking, from ancient Roman gladiators to modern-day sanguinarians.

Most Americans are now dying at home, reversing 20th century trends

For most of the 21st and 20th centuries most Americans died in hospital settings. But in 2016, home-based deaths overtook hospitals; most Americans are now dying at home, likely fueled by individual preferences to die at home or to receive at-home palliative care.

Find fertility clinics and their success rates in your state

This database from the Centers for Disease Control and Prevention provides a searchable portal of fertility clinics across the US, with reported data on services, total procedures performed, and live births recorded for as recently as 2022.

Timeline of cancer research milestones

While cancer remains incurable, there's been so much progress in its treatment over the last two decades. Nature provides an abridged history of milestones and major triumphs in cancer research and treatment. Start in the year 2000, and see how much has changed in the first quarter of the new millennium

A history of "Memento Mori," from the ancients to today

The ancient Latin phrase 'memento mori' means 'remember you will die.' The counterintuitive utterance has long provided a moral and spiritual framework for individuals to evaluate their life's decisions and worldview. Though it appears morbid at first glance, the saying is meant to inspire a thirst for life. Review the various ways the idea has inspired different cultures in this article, from the Romans and Egyptians to contemporary tech leaders like Steve Jobs.

The human cost of creating medieval monsters

The concept and creation of monsters have been used since time immemorial to communicate social norms and the consequences of breaking them. Some so-called monsters were judged as such solely due to having features that would be considered birth defects in modern times. This in-depth article explores the human cost of creating medieval monsters, many of whom were defined by a physical appearance that deviates from the expected.

Estimates suggest inactivity contributes to 6% of deaths worldwide

The World Health Organization identifies physical inactivity as the fourth leading modifiable risk factor for global mortality, just behind hypertension, tobacco use, and high blood glucose. Latest estimates are that inactivity contributes to 6% of deaths and significantly increases the burden of chronic diseases like heart disease, diabetes, and cancer.

Humans have existed for just 0.004% of Earth’s history

Born from the remains of the molecular cloud that birthed the sun, Earth experienced planetary-scale collisions, asteroid impacts, and lava seas. Life became possible after the planet cooled and formed a thin crust, atmosphere, and oceans.

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.