Alzheimer's is most prevalent in the South and the East

Alzheimer's disease is the leading cause of dementia and risks rise after age 65

Read this primer about Alzheimer's disease and learn what factors increase the risk of this form of dementia, including genetics, being a woman, and health conditions, including high blood pressure.

Five to ten percent of Alzheimer's cases are early-onset

Early-onset Alzheimer’s typically emerges around 40 to 50 years of age, with devastating effects. This video follows Brian, diagnosed with the disease at age 54, as he travels the country as an advocate for research and discusses the progressive mental fog of Alzheimer’s.

See MS prevalence by region in the United States

This map underscores that people in the northeastern United States have more cases of the disease as compared to the south, west, and midwest. On an individual level, these numbers may still differ based on genetic makeup and other factors irrespective of where people live.

Listen to how one gene affects Alzheimer's risk

Multiple genes are associated with Alzheimer's risk, but one well-known disease-associated gene is the apolipoprotein E (APOE) gene, which is typically involved in making a protein that helps carry cholesterol and other fats in the bloodstream. Specific variants of this gene are associated with elevated disease risk, though even if someone has two copies of the disease, that doesn't mean they will definitely develop Alzheimer's.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Poor sleep increases the risk of developing Alzheimer's

Brain imaging studies reveal poor sleep leads to production of amyloid beta proteins—molecules linked to Alzheimer’s—which are cleaned from the brain during high-quality sleep. These findings suggest conditions like sleep apnea and insomnia increase the risk of developing the disease.

Alzheimer's can cause brain shrinkage of between 10% and 30%

While the exact cause of Alzheimer's is debated, the buildup of amyloid plaques and tau protein tangles is instantly recognizable in post-mortem examinations. The atrophy of brain cells caused by this molecular pileup leads to noticeable physical changes, including significant shrinkage in affected brain regions.

Millions of aging Americans are facing dementia or cognitive impairment—alone

An estimated 4.3 million people aged 55 or older who have cognitive impairment or dementia live alone in the US. The individuals facing these challenges are more likely to be women, people of color, and to generally be poorer and less educated than other older adults who are also living alone.

Does our fear of Alzheimer's create stigma around its treatment?

Surveys suggest our fear of Alzheimer's as a disease outranks that of heart disease and cancer. This piece argues our fear of aging and the slipping away of our mental capacities make it more difficult to treat Alzheimer's compassionately.

There are two FDA-approved blood tests that may detect early Alzheimer's disease

Yet the tests are only recommended for those who have symptoms of dementia, and are not definitive on their own. False positives are a concern with these new tests, which detect biomarkers that may indicate the presence of brain proteins linked to the disease. This podcast explores the state of research on the disease and concerns about regulators taking jobs at pharmaceutical and biotech companies, which may influence their approach to approvals. It also dives into an investigation about the data underpinning one experimental Alzheimer's drug.

Caucasians are at the greatest risk of developing macular degeneration

A 2016 analysis across ethnic groups found, among other things, that white participants had the highest incidence of the disease, followed by Chinese, Hispanic, and Black participants. This study did not answer why that may be the case.

Smell is a robust memory cue for individuals with Alzheimer's disease

Odor is more effective than both visual and verbal cues for triggering autobiographical recall in Alzheimer's disease, according to 2021 research.

In 2023, Native Americans had the lowest life expectancy at birth among all racial and ethnic groups

Native Americans and Alaska Natives face significant health disparities linked to chronic underinvestment in reservation health infrastructure, poverty, and multigenerational psychological harm—often called historical or inherited trauma.

Autoimmune disease prevalence and incidence are on the rise—but no one knows why

Researchers theorize that environmental factors, including shifts to less healthy diets, air pollution, infections, stress, climate change, and exposures to xenobiotics—substances like pesticides, plastics, and toxins that incite immune responses—may all be fueling epigenetic changes to our bodies that make people's immune responses go awry.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

How race science influences breast cancer research

Despite researchers' and physicians' pushback, race is still used in studies and clinics to categorize human differences in health conditions and treatment responses. This article explores how race has influenced breast cancer research. Considering race as a factor in cancer research, diagnosis, and treatment can lead to racial inequalities. Sociocultural factors, including food access and air pollution, greatly influence health outcomes.

What the research says about the link between lead pollution and crime

The lead-crime hypothesis links childhood lead exposure to impulsivity and aggression as an adult, traits typically associated with higher crime risk. A 2022 meta-analysis found that reducing lead may explain up to 28% of the US homicide decline, but not the broader crime drop.

Age, stress, and neurological disorders can prevent memory formation and recall

Neurons transmit signals between one another at sites called synapses. Repeated interactions at these sites improve the efficiency of signal transmissions, making memories involving sensory data associated with those neurons easier to recall. Biochemical factors impacting these synaptic interactions affect memory quality.

As of 2026, the majority of US states have unsafe radon exposure levels

Alaska, South Dakota, Pennsylvania, Ohio, and Washington top the list of states with exposure levels above 4 picocuries per liter for this naturally occurring radioactive gas. While these state-level averages vary from one county, municipality, and home to another, the EPA encourages those in the highest-risk states to test their homes.

Louisiana's 'Cancer Alley' has cancer rates 50% above the national average

Due to its proximity to Gulf oil production, an 85-mile stretch of highway linking Baton Rogue, Louisiana, and New Orleans is home to 25% of the country's petrochemical manufacturing. It's also one of the most polluted regions of the US, with cancer rates at 50% above average.

Blue zones are regions with unusually high numbers of centenarians

Factors thought to contribute to longevity in these regions include diet and social connections, but their legitimacy is often questioned due to a lack of rigorous scientific methodology and potential record inaccuracies.

Alaska has the highest lifetime credit card debt of all US states at $484,620

That's 21.8% above the national average, partly due to Alaska's high cost of living and remote nature, which makes shipping in food and fuel more expensive. Iowa had the lowest average lifetime credit card debt out of all the states in the US at $319,740.

China reports the highest prevalence of hearing loss and South Africa reports the lowest

This conclusion comes from research published in 2025 that analyzed self-reported hearing loss and hearing aid use from long-term studies that covered 28 countries. Its findings included that the countries with the greatest prevalence of hearing loss (China, South Korea, Mexico, and Brazil) also had the lowest levels of hearing aid use.

These areas of the brain are hard-hit in depression—but the changes are reversible

Depressed brains can have certain characteristic changes, including an overactive amygdala, reduced hippocampus size, and changes to the thalamus and neuromodulating chemicals in the brain.

Autism rate increases are mostly among those with milder symptoms, not individuals with severe symptoms

Broader case definitions and better screening are typically now detecting more milder cases of autism rather than individuals who have severe impairments (who could be categorized as having profound autism). Profound autism rates, an autism researcher says in this article, have stayed proportionately steady.

A third of Americans now live in wildfire risk zones

Climate change and human development into fire-prone regions have extended the wildfire season, with some areas experiencing fire conditions year-round. Extreme conditions, poor compensation, and exposure to carcinogens have complicated firefighter recruitment, further exacerbating wildfire risks.

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.

Poison ivy will likely become both larger and more resilient due to climate change.

44% of Americans say they pray at least once a day—discover how your state's religiosity stacks up against the rest of the country.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

Play the role of a student in a game where you try to navigate college and remain debt-free, selecting different income levels, high school experience, race, ethnicity, and more.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

Animal phobias are likely the most common type of phobias, followed by an extreme fear of heights.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

Ebola species have historically been named after where they were discovered, stigmatizing residents who live there, including Bundibugyo, in Uganda.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

In 2026, Finland was named the world's happiest country for the ninth consecutive year based on its wealth, social safety network, and high life expectancy, among other factors.

Fireworks-related ER visits are on the rise—in 2024, they increased by 52% as compared to the prior year.

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Art theft is the third-largest source of criminal revenues worldwide, thanks in part to the subjective nature of valuing a work of art.

The Nasdaq's 'Magnificent 7' companies are responsible for roughly 40% of the Nasdaq 100 index's gains, while the remaining 93 companies account for the other 60%.

Search a massive database of over 4 decades of clues from the TV quiz show 'Jeopardy!'

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.