Vox.com has a new series called The Goods whose first article has the kind of journalistic quality (or lack thereof) you would expect in a series that seems to be purely about product placement. The article, by Kaitlyn Tiffany, is about Pedialyte which happens to be a bit of a passion of mine because the simple technology upon which it is based has saved millions of lives and transformed the world more than perhaps any other medical treatment in history except antibiotics and vaccines. And unlike vaccines and antibiotics which everyone knows and understands–at least minimally–the miracle of oral rehydration therapy is unsung.

Unfortunately, Kaitlyn Tiffany misses most of the miraculous story and gets several details completely wrong.  First she says that “Pedialyte has been sold over the counter in pharmacies since the 1960s.” That can’t be true because Pedialyte didn’t even exist as a brand in 1960. The trademark for Pedialyte was filed in 1974 according to the US Patent and Trademark Office. Google shows that the word “Pedialyte” was never written in English publications until 1975. Then she says it is based on one of the oral rehydration therapies “invented by the World Health Organization in the 1940s”. That is also false because although there were numerous oral rehydration therapies used by all sorts of people for millennia, they were completely haphazard and most probably did more harm than good because the science was insufficient to actually know what worked (and how it worked) until around 1970.

There are still therapies that market themselves for “oral rehydration” that don’t actually work like Gatorade which makes a ton of money on dubious rehydration claims, so it is certainly true that there were therapies that claimed to work for oral rehydration in the 1940s (or 1640s), but they only accidentally worked sometimes when someone got lucky and happened to mix up a formula with the right ratios of electrolytes. It is hard to trust any of the rest of the article when it gets such basic facts wrong.

But the rest of the article is mostly about corporate marketing to push the recent Pedialyte fad for hangover cure, so if it isn’t perfectly accurate, it probably isn’t very important because it is a fascinating case study in marketing.  Oral rehydration therapy is a super important topic, and I’m thrilled to see journalists working on it but for a more accurate and more informative article than Vox’s, check out my primer.

One fact that I would have been really interested in learning is why Pedialyte is so ridiculously expensive. The profit margin must be enormous. The ingredients are all really cheap. They are nearly the same as the ingredients in Gatorade which sells for a fraction of the price. The main difference between the two is that there are more salts and less sugar in Pedialyte. So why the huge difference in price?

Christie Aschwanden wrote about Gatorade marketing at 538 which she believes has resulted in athletes dying of excessive hydration. The story of the backlash against over-hydration begins at the 1981 Comrades 90-kilometer ultramarathon in South Africa.

It was the first time that the event had provided drink stations every mile of the 56-mile course…  the runner [began] feeling really strange about three-quarters of the way through the race. Her husband pulled her off the course and delivered her to the medics. The first responders assumed she was dehydrated and gave her two liters of intravenous fluid, after which she lost consciousness. She had a seizure on the way to the emergency room.

At the hospital, doctors discovered that her blood sodium concentration was dangerously low. The ultimate diagnosis was a medical condition called “water intoxication” or hyponatremia — too little sodium in the blood. Contrary to what the medical crew at the race had assumed, the runner wasn’t dehydrated— she was overhydrated. She’d drunk so much fluid that her blood sodium had become dangerously diluted. Low blood sodium causes cells in the body to swell, and when it happens in the brain, the results can be deadly.

…the rush to prevent dehydration may have put exercisers at risk of the far more serious condition of water intoxication. In 1986, a research group published a paper in the Journal of the American Medical Association describing the experience of a medical student and a physician who’d become stuporous and disoriented during an ultramarathon. The men were diagnosed with hyponatremia, and they concluded that they’d developed the condition by drinking too much.

There’s never been a case of a runner dying of dehydration on a marathon course, but since 1993, at least five marathoners have died from hyponatremia they developed during a race.⁶ At the 2002 Boston Marathon, …samples showed that 13 percent of the runners had diagnosable hyponatremia, and three had critical cases… German researchers similarly took blood samples from more than a thousand finishers of the Ironman European Championship over multiple years and found that 10.6 percent of them had hyponatremia. …nearly 2 percent of the finishers had severe or critical cases. Although the findings indicate that hyponatremia is still a rare condition, what makes them especially concerning is that the early symptoms of hyponatremia are very easily confused with those of dehydration — weakness, headache, nausea, dizziness and lightheadedness.

Confusing hyponatremia with its opposite condition can lead to deadly treatments like the intravenous fluid injections.  It turns out that athletes should listen to their bodies rather than to marketers to decide how much to drink.  Healthy people don’t need to be reminded to sleep when they are not tired and similarly they don’t need to be reminded to drink when they are not thirsty.  Sick people, on the other hand, if they have serious diarrhea and are too sick to realize what they need should be reminded to drink oral rehydration therapy.  Unlike athletes, people with diarrhea do die of dehydration even when there are plenty of fluids available for them to drink.