One doctor argued vampires were based on a real disease

The word 'vampire' appeared in the English-speaking world in the 1730s

However, earlier mentions of creatures with similar characteristics existed throughout Medieval Europe. For example, people often spoke of revenants—restless dead creatures who tormented the living. Historians believe these stories grew in popularity in part because of influence from the Catholic Church, which was emphasizing the idea of purgatory. These older revenant stories eventually influenced modern vampire folklore.

The Dracula character, now seen as the vampire archetype, was inspired by a seafood-induced nightmare its creator experienced.

Vampire bats are the only mammal to feed exclusively on blood

Scientists believe their ancestors may have eaten parasites and insects off larger animals until vampire bats started feeding directly from those animals. Colonies work together to stay fed, as a vampire bat can die without just two days of eating.

'Dracula' was inspired by a seafood-induced nightmare

Bram Stoker, the author of the classic horror novel, said that a dinner of "dressed crab" led to unsettling dreams about "a vampire king rising from the tomb." He'd revisit that vision, eventually creating the iconic titular vampire.

The history of blood, as told by a hematologist

Since ancient times, blood has been seen as a semi-magical substance. Alchemists theorized it was a mixture of the four elements. Others proposed it was one of four bodily fluids whose balance dictated health. This 2019 essay by a hematologist reviews blood's reputation across cultures and centuries.

The ‘Universal Monsters’ series solidified horror as a film genre

Before 1931, most scary movies were billed as “mystery” or “suspense” with grounded explanations for anything "supernatural." That changed with “Dracula,” which presented the character as a real vampire who drank victims' blood. Universal continued adapting similar titles, including HG Wells’ “The Invisible Man” and Edgar Allan Poe’s short stories.

The virus was officially described for the first time in 1789

Michael Underwood, an English physician and surgeon, was the first to describe the disorder, noting it caused disability in the lower extremities in children. Large-scale outbreaks of the disease were not observed until the late 19th century.

Before vaccines, there was 'variolation': what was it?

Before the technology behind vaccinations was discovered, some keen observers of medicine around the globe noticed how previous infections could impact future ones. Learn about the techniques early physicians used before they had vaccines.

Historians theorize Vincent Van Gogh suffered from Ménière's disease or epilepsy

A century after researchers suggested he suffered from epilepsy, some researchers in the 1990s began to support an alternate diagnosis: Ménière's disease, since he had suffered from severe, repeated attacks of disabling vertigo. Still, some researchers remain skeptical of the Ménière's diagnosis. One posits that Van Gogh had temporal epilepsy complicated by his absinthe consumption.

In 1892, two scientists purposefully infected themselves with cholera bacteria

When they became ill—one with mild diarrhea and the other with severe cholera—researchers pointed to that as proof that the pathogen caused the disease.

The Hungarian countess rumored to have bathed in blood

According to legend, Hungarian countess Elizabeth Báthory killed up to 600 women to bathe in their blood and preserve her youth. Such allegations have been challenged since the 1980s when Slovakian archivist Josef Kocis published a book detailing new aspects of Báthory's life and included possible evidence of a conspiracy meant to undermine her power as part of Transylvania's ruling dynasty.

A pediatric journal ran 138 fictional case studies, and 61 were cited as real stories

The Canadian journal Paediatrics & Child Health issued corrections to 138 case studies published since 2000, acknowledging the cases were entirely fictional—a practice intended to protect patient privacy that was never disclosed to readers. At least 61 of the fabricated reports were cited as fact in other peer-reviewed journals a combined 218 times, including a 2006 Lancet article alleging an infant died from opioid-laced breast milk.

Scientists found that if cats in the lab ate infected rodents they could get West Nile

But beyond the lab setting there have been no known cases of cats or dogs contracting the virus this way. Instead, those animals have been sickened when an infected mosquito bit them—just as with human infection.

Lupus, an autoimmune disease with varied symptoms, was named for wolf bite-like lesions

The 13th-century physician behind the name (lupus is Latin for wolf) named it after a patient he saw who had facial lesions that looked to him like a wolf's bite. Other common symptoms of the disease include extreme fatigue, painful and swollen joints, fevers, and light sensitivity.

How the most famous Ebola outbreak book got aspects of the disease so wrong

Richard Preston's 1994 book The Hot Zone brought knowledge of Ebola to the masses. But, beyond the poor portrayals of the science and the scientists, the book fostered fearmongering about Ebola, with portrayals of "liquefying," "dissolving," and "bleeding out." These falsehoods about Ebola have persisted for decades and appear to be reinvigorated with every new emergence of the disease.

Watch how viruses like Ebola can spill over from animals to humans—and vice-versa.

Explore illustrative depictions of Chernobyl in comic books

Pieces related to the location since the nuclear disaster have told stories about radioactive vampires and monsters, accounts of bureaucratic corruption and creed, and visual retellings of experiences those in the region lived through before and after the event.

History's weirdest weight loss fads, fact-checked

Nothing catches popular attention more than a claim to have found a quick weight-loss technique. History shows us such claims are often unfounded. Dr. Michael Mosley explores extreme weight-loss tips from history, from tapeworms to vinegar diets.

Hit show 'The Last of Us' was based on the real-life Cordyceps fungus

Though it depicted a fictional world with a collapsed society due to a fungal pandemic, this television series (based on an earlier video game) helped raise awareness about fungal threats. It even prompted the US Centers for Disease Control and Prevention to publicly comment on it—clarifying the show’s plausibility. The mind-controlling fungal species in the show is based on a real-life Cordyceps species, a fungus that modifies its host’s behavior before killing it.

How the most famous Ebola book, The Hot Zone, which sold 3.5 million copies and was translated into 30 languages, got aspects of the disease so wrong.

After the patient died, a latent pig virus was discovered inside his xenotransplant

Researchers studying the death of David Bennett Sr., the first gene-edited pig heart transplant patient, discovered potential factors that may have contributed to his demise. One finding is that there was a latent virus, called porcine cytomegalovirus (PCMV), in the pig heart, which may have contributed to dysfunction of the transplant.

Imagining how genetics works in 'Harry Potter' and how muggle-born Hermione is a witch

Dr. Robert Pyatt, director of Sanford Health’s medical genetics lab, talks through real-world genetics scenarios in the Harry Potter series, from the Weasley's red hair and freckles to why Hermione, a witch, could be born to "muggle"—or nonmagical—parents.

The concept of phantom limbs, the perception that amputated limbs are still present, dates back to a French military surgeon in the 16th century.

Cold-blooded reptiles seek heat, and that behavior may help combat fungal infections

This Radiolab podcast episode takes on the idea that though our human bodies are too warm for the majority of fungal species to effectively replicate inside our bodies, that's not the case for reptiles. Yet when those species warm their bodies by basking in the sun on rocks, they can soak up heat and may also help keep fungal infections in check.

The ‘paranormal activity’ lab at the University of Virginia

Near-death experiences aren’t the only thing they study at Greyson’s Division of Perceptual Studies. The lab approaches a host of “paranormal” phenomena—like past lives and out-of-body experiences—with the same academic rigor as the physics or economics department.

Some say baseball's drug problem goes back to the late 1800s

At age 32, pitcher James “Pud” Galvin was feeling tired and decided to take "the Brown-Séquard elixir," which contained a testicular fluid from dogs and guinea pigs, believed to invigorate tired bodies. It might've worked: Galvin pitched a two-hit shutout the next day.

Roughly 1 in 5 cancers are caused by viruses

About 20% of cancers are caused by viruses, with seven specific oncoviruses causing between 10% and 15% of cancers worldwide. These include human papillomavirus and hepatitis B and C viruses, which can lead to diseases such as cervical and liver cancer. Understanding the mechanisms of these viruses is crucial for prevention and treatment strategies.

A dispute about the origin of twitching frog legs led to the invention of the first battery

Experiments by Luigi Galvani on exposed frog leg nerves showed activity when they were hung from iron railings and brass hooks, suggesting the existence of "animal electricity" that discharged when connected to metals. Alessandro Volta's voltaic pile, which stacked metals with an inorganic electrolyte, showed that electricity originates from chemical reactions.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Vitamin D supplement pills are linked to rising cases of vitamin D toxicity in the US

Vitamin D deficiency is common. But taking Vitamin D supplements in doses exceeding 4,000 IU/day (a measurement of vitamin biological activity) for prolonged periods can raise bodily concentrations of this vitamin to dangerous values. US National Poison Data indicates that the annual average of vitamin D poisonings from 2000-05 was 196, but this rose by 1,600% to 4,535 per year for the period of 2005-11.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Poison ivy was sent to Europe in the 1600s as an exotic, ornamental oddity, where it was purposefully grown in the English royal gardens at Kew, the Faculty of Medicine in Paris, and a few other locations.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

Some Pokémon have been named after real and fictional organisms, while some real-world species have been named after Pokémon, such as Chilicola charizard and Binburrum zapdos.

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

'Saturday Night Fever,' the 1977 film that introduced disco to the mainstream, was based on a fabricated magazine story.

See images of medical cases of firework injuries shared on this 'Instagram for doctors.' (Warning: Graphic content)

Elk Cloner, the first computer virus to spread in public, was written as a practical joke by Richard Skrenta, a Pittsburgh high school student.

Many legends about George Washington, including his supposed wooden teeth and the story of cutting down the cherry tree, lack evidence.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

About 12.5% of US adults experience a phobia in their lifetime, a diagnosis that hinges on the intense fear interfering with daily life and persisting for at least six months.

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

The Brothers Grimm were lawyers before they were storytellers, and became interested in fairy tales as they began investigating how rules and customs had been passed down through cultures.

The tragic Pulitzer Prize-winning image 'The Vulture and the Little Girl' (1993) generated controversy, raised concerns about ethics in photography, and eventually led to the photographer's death.

A researcher recently discovered an interview from 1967 between groundbreaking journalist Joan Didion and the Grateful Dead, years before the band became an institution.

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

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.