In 2008, Paul Karason, a 57-year-old man from the Pacific Northwest, agreed to appear on the Today show. And appear is the best word for it, since he was there because of the way he looked. From head to toe, Paul Karason was the color blue. Not a subtle light-wash tint, either. This was closer to navy—like Beast from the X-Men or some elder Smurf. His graying auburn hair heightened the effect; the whites of his eyes had a leaden tint. “I’ve gotten kind of used to it,” he told Matt Lauer. He wasn't always this way. For most of his life, Karason was a fair-skinned redhead. But then he saw an ad in a magazine showing a desiccated old daisy brought back to life by the power of the solution it had been placed in: silver ions in water. The flower looked freshly cut. Karason bought a device to make his own colloidal silver at home—a colloid is one substance dispersed through a second—and soon he was drinking a 10-ounce tumbler of the stuff daily, hoping to improve his general health, and dabbing it on his face for his dermatitis. After a few years of this regimen, he had developed a case of what doctors call argyria, a blue-gray discoloration of the skin and mucus membranes. View more Heidi Gutman/NBC NewsWire/Getty Images The disorder is caused by excess silver ions in the body, which react when exposed to light (the same phenomenon that makes silver nitrate useful for developing photos) and form dark deposits in the skin. It’s a rare but irreversible condition, and in most cases the culprit is overenthusiastic use of colloidal silver. Karason wasn't the only victim. Stan Jones, a libertarian politician from Montana, started taking colloidal silver in advance of Y2K, assuming the new millennium would cause a shortage in antibiotics. A Montessori teacher from Brooklyn, Rosemary Jacobs, became known as the “silver woman” for the argyria she developed from colloidal silver nasal drops a doctor prescribed her as a child. None of this has stopped people from ingesting colloidal silver, though. In fact, its popularity only seems to have increased in recent years. Celebrities ranging from Alex Jones, the host of the far-right radio show Infowars, to Gwyneth Paltrow, she of the jade egg and wellness brand Goop, have enthusiastically promoted the potion; you can find it on the shelves of your local Whole Foods. Yet there's very little mainstream evidence of its usefulness. According to the Mayo Clinic, colloidal silver “isn’t considered safe or effective”; the NIH warns that “evidence supporting health-related claims is lacking” and that “it can be dangerous to your health.” And, of course, overuse risks turning you blue forever.

Silver has been a favored defense against infection since ancient times. Pliny the Elder reported in AD 78 that silver slag, the gunk left over from smelting silver, “has healing properties as an ingredient in plasters,” and Cyrus the Great, king of Persia from 550 to 529 BC, stayed healthy by drinking only boiled water stored in silver flagons. (According to Herodotus, mule-drawn carts laden with silver urns followed King Cyrus “whithersoever” he went.) During the Middle Ages, monks popularized the use of silver nitrate, a salt formed by reacting silver with nitric acid, to treat ulcers and burns. Relative to other premodern health tips, these were actually pretty good ideas, because—as scientists discovered once they finally figured out germ theory—silver does have germ-fighting abilities. The exact mechanism by which it attacks bacterial cells still isn’t clear, but scientists have some guesses. Silver is most toxic to microbes in its ionized form—AG+, same as in those silver nitrate salts—which seems to deactivate important microbial enzymes and potentially screw with DNA replication. More Health Trends In Depth Science Forget the Blood of Teens. This Pill Promises to Extend Life for a Nickel a Pop The more researchers learn about a compound called metformin, the more it seems like a medieval wonder drug poised for a 21st century comeback. Public Health Don't Fall for the 'Memory' Pills Targeting Baby Boomers Prevagen is just one of many nootropics on the market, each aimed at a different kind of audience. And none of them have much science behind them. Health The Weird Business Behind a Trendy "Anti-Aging" Pill Elysium has attracted press because of its scientific stars, but it’s ChromaDex that is quietly blurring the boundary between drug and supplement. Through the 1960s, most American newborns received silver nitrate eyedrops at birth to prevent eye infections. It’s occasionally still used for that purpose, but silver nitrate had a bad side effect: It burns skin and can cause severe eye damage. That's why, starting in the early 20th century, scientists started suspending silver in water. Protein molecules in the solution surrounded the silver ions, so that only some—but not all—of the ions were released. The idea was to make a formula that was much less irritating than silver nitrate but equally effective at killing bugs. “In fact,” wrote Henry Crooks, one of the early pioneers, in 1910, “no microbe is known that is not killed by colloidal silver in laboratory experiments in six minutes.” But the colloidal silver solutions were problematic too. It’s very difficult to control or analyze how much of the silver is ionized, so a patient has no way of knowing how much active silver they’re ingesting or applying—rendering it either useless or, on the other extreme, so potent it results in argyria. So colloidal silver was mostly abandoned by the medical establishment, which moved on to safer and more effective applications of silver, such as in wound dressings or as an infection-fighting additive to joint replacements. Recent tests of modern colloidal silver products found they had no significant antimicrobial properties and left most bacteria unscathed (even after six minutes). Even so, colloidal silver never left the drugstore shelves. In 1999 the FDA declared that over-the-counter products containing colloidal silver ingredients were “misbranded” and “not generally recognized as safe,” banning its sale as an OTC drug. But in practice that just means it sits on a different shelf in the pharmacy, as a supplement now instead of a medication.

Alex Javier and Deb Blossom are not acquainted—nor, in the current political climate, would they likely want to be. Javier is a Ron Paul–loving libertarian who voted for Trump without much hesitation; Blossom was a Bernie fan who happily voted for Hillary. But they have more in common than they might think. Blossom is a yoga teacher, life coach, and energy worker in Santa Monica, California. When she was a child, she watched her mother battle cancer and go through painful chemotherapy that was ultimately unsuccessful. She died when Blossom was 11. Then, in her twenties, Blossom watched her mentor and teacher endure the same experience. “Chemotherapy is being sold to a lot of people who don’t need it,” she says. Though Blossom stops short of writing off Western medicine altogether—she thinks it has its strengths, mostly as a diagnostic tool—she’s certainly a skeptic. Javier’s skepticism was shaped by a similar experience. It started during high school. He had always been a rowdy kid, playing sports to keep his energy in check, but in his sophomore year, Javier's doctors and mom decided his hyperactivity needed to be addressed medically. He ended up on a combination of four psychoactive drugs. The side effects were disastrous: He lost 30 pounds, became depressed, and suffered narcoleptic paralysis—waking up without being able to move his body. “It scared the crap out of me,” he says. Javier is now 36 years old and living in Hartford, Connecticut, where he keeps up a hodgepodge of odd jobs, usually as a substitute teacher or musician. To fill the gaps between work, and for company during his long nights (he’s a serious night owl), he listens to the radio. Local shows sometimes, but also a lot of Infowars, his source for political and medical advice. It was during one of his late-night radio sessions that Javier first started hearing ads for colloidal silver. When a bad flu was going around a few years ago, most of Javier’s friends who got sick ended up taking antibiotics. Javier generally refuses to take antibiotics, so he tried colloidal silver instead. He took it every day, doling out an entire bottle until he was healthy, and he believed he got better faster than his friends. Now he takes it when he has a stomachache or if he thinks he was exposed to something while teaching. “You see what works for you,” he says. “In my experience this works.” Blossom—who has a very different media diet—also keeps colloidal silver handy. She mostly uses it for cuts and scrapes on herself and her dog. “It works incredibly effectively and quickly,” she says. “I've been using it for years.” Like Javier, she thinks the most important thing she can do for her health isn’t to heed the FDA’s warnings but to trust her instincts and her own research. “I don’t subscribe to what the FDA says, nor do I subscribe to what the medical community says, generally,” Blossom says. “I don’t think they are pure in their intentions.” “The pharmaceutical industries have to raise profit,” Javier says. “So they’ll do anything they can to increase profit, and if that means suppressing information … I'm not going to say lie, but there have been a lot of false things.” Blossom makes the same argument: “The pharma companies' interests are in money, not at all in healing people. It’s a business.”