When Kathleen Walker-Meikle, a historian at the University of Basel, in Switzerland, ponders the Middle Ages, her mind tends to drift not to religious conquest or Viking raids, but to squirrels. Tawny-backed, white-bellied, tufted-eared red squirrels, to be exact. For hundreds of years, society’s elites stitched red-squirrel pelts into luxurious floor-length capes and made the animals pets, cradling them in their lap and commissioning gold collars festooned with pearls. Human lives were so intertwined with those of red squirrels that one of history’s most cursed diseases likely passed repeated ..read more

Earlier this week, news leaked of the biggest change in federal drug policy in more than half a century. The Associated Press reported—and the Department of Justice later confirmed—that the Drug Enforcement Administration plans to recategorize marijuana under the Controlled Substances Act. Since the 1970s, it’s been placed in Schedule I, a highly controlled group that includes drugs like heroin, with a high potential for abuse and no medical use. But cannabis will soon be moved to the much less restrictive Schedule III, which includes prescription drugs such as ketamine and Tylenol with codein ..read more

Milk is defined by its percentages: nonfat, 2 percent, whole. Now there is a different kind of milk percentage to keep in mind. Last week, the FDA reported that 20 percent of the milk it had sampled from retailers across the country contained fragments of bird flu, raising concerns that the virus, which is spreading among animals, might be on its way to sickening humans too. The agency reassured the public that milk is still safe to drink because the pasteurization process inactivates the bird-flu virus. Still, the mere association with bird flu has left some people uneasy and led others to av ..read more

It takes a certain amount of confidence to call your biotech company Grail. According to its website, the Menlo Park–based firm got its name because its “co-founders believed a simple blood test could be the ‘holy GRAIL’ of cancer detection.” Now the company claims that its “first-of-its-kind” screening tool, called Galleri, “redefines what’s possible.” At the cost of a needle stick and $949, the company can check your blood for more than 50 forms of cancer all at once. The Galleri test, as well as many others of its type that are in development, is meant to sniff out malignant DNA floating in ..read more

Reading, while not technically medicine, is a fundamentally wholesome activity. It can prevent cognitive decline, improve sleep, and lower blood pressure. In one study, book readers outlived their nonreading peers by nearly two years. People have intuitively understood reading’s benefits for thousands of years: The earliest known library, in ancient Egypt, bore an inscription that read The house of healing for the soul. But the ancients read differently than we do today. Until approximately the tenth century, when the practice of silent reading expanded thanks to the invention of punctuation ..read more

A few months ago, my doctor uttered a phrase I’d long dreaded: Your blood sugar is too high. With my family history of diabetes, and occasional powerful cravings for chocolate, I knew this was coming and what it would mean: To satisfy my sweet fix, I’d have to turn to sugar substitutes. Ughhhh. Dupes such as aspartame, stevia, and sucralose (the main ingredient in Splenda) are sweet and have few or zero calories, so they typically don’t spike your blood sugar like the real thing. But while there are now more sugar alternatives than ever, many people find that they taste terrible. The aspartame ..read more

In the fall of 2021, Gabriel Arias felt like his body was “rotting from the inside.” He was diagnosed with acute myeloid leukemia, a form of blood cancer so aggressive that doctors had him hospitalized the day of his biopsy. In cases like his, the ideal treatment is a transplant. Arias’s cancer-prone blood cells needed to be destroyed and replaced with healthy ones taken from the bone marrow or blood of a donor who matched him biologically. Fortunately, doctors found him a match in the volunteer-donor registries—a man in Poland. Unfortunately, Arias’s single match in the entire world was no lo ..read more

After a decade working as an obstetrician-gynecologist, Marci Bowers thought she understood menopause. Whenever she saw a patient in her 40s or 50s, she knew to ask about things such as hot flashes, vaginal dryness, mood swings, and memory problems. And no matter what a patient’s concern was, Bowers almost always ended up prescribing the same thing. “Our answer was always estrogen,” she told me. Then, in the mid-2000s, Bowers took over a gender-affirmation surgical practice in Colorado. In her new role, she began consultations by asking each patient what they wanted from their body—a question ..read more

In December 1921, Leonard Thompson was admitted to Toronto General Hospital so weak and emaciated that his father had to carry him inside. Thompson was barely a teenager, weighing all of 65 pounds, dying of diabetes. With so little to lose, he was an ideal candidate to be patient No. 1 for a trial of the pancreatic extract that would come to be called insulin. The insulin did what today we know it can. “The boy became brighter, more active, looked better and said he felt stronger,” the team of Toronto researchers and physicians reported in March 1922 in The Canadian Medical Association Journal ..read more

Good chocolate, I’ve come to learn, should taste richly of cocoa—a balanced blend of bitter and sweet, with notes of fruit, nuts, and spice. My favorite chocolate treat is nothing like that. It’s the Cadbury Creme Egg, an ovoid milk-chocolate shell enveloping a syrupy fondant center. To this day, I look forward to its yearly return in the weeks leading up to Easter. Most popular chocolate is like this: milky, sugary, and light on actual cocoa. Lots of sugary sweets contain so little of the stuff that they are minimally chocolate. M&M’s, Snickers bars, and Hershey’s Kisses aren’t staples of ..read more