Adelle Davis

Adelle Davis, circa 1925

Adelle Davis was the most popular and influential writer on food and nutrition in the United States from the 1950s through the 1970s. Yet many nutrition experts considered her to be a dangerous source of false information. This is surprising, considering how closely most of her advice adhered to the standard “Four Food Groups” being promoted by the USDA at the time. Yet some of the advice she provided in her books proved to be even more deadly than the standard American diet.

Daisie Adelle Davis, born in 1904, was one of the few popular writers about nutrition to have had any scientific training in the field. She was trained as a dietitian at Bellevue and Fordham Hospitals in New York City in the late 1920s, and she earned a master of science (MS) degree in biochemistry from the University of Southern California in 1939. Despite her education in science and nutrition, Davis’s popular books on nutrition were riddled with scientific errors. Although Davis cited 2,402 references as “documentation” in her book Let’s Get Well, many of those references either had nothing to do with the subject she was discussing or flatly contradicted the arguments she was making.[1] Experts whose work she cited in the book complained that they had been misquoted or their statements taken out of context. Some of the misinformation and bad advice in Davis’s books proved deadly, even to herself.

At least one death,[2] and one near miss,[3] occurred in babies who had been given large doses of potassium, because of bad advice that Davis gave in Let’s Have Healthy Children. Davis had falsely claimed that “colic” in babies is due to potassium deficiency, which she mistakenly said was due to eating too much sodium. She falsely claimed, “most babies needed 3,000 milligrams of potassium chloride (2/3 teaspoon) before colic was corrected.” Unfortunately, the article she cited said nothing of the kind.[4] It wasn’t even about colic, a term used to describe children who cry nonstop for hours, often with signs of gas or bellyache. Instead, the article was about hospitalized children who had low potassium levels because of severe vomiting and diarrhea. The article described doses of 1000 to 2000 milligrams being given gradually over 24 hours, not a dose of 3000 milligrams given all at once. Furthermore, the article specifically warned that giving potassium to a dehydrated infant could cause cardiac arrest.[5]

Other children were seriously harmed by Davis’s advice to give children large doses of vitamin A. One child who had vitamin A overdose as a result was hospitalized with symptoms that suggested brain tumor. This condition, called pseudotumor cerebri, is a form of brain swelling that can destroy the optic nerves, leading to permanent blindness, or even cause death. Another child’s growth was permanently stunted by vitamin A overdoses after a parent took Davis’s advice.

Davis herself died of breast cancer in 1974. We know now that the rate of breast cancer in a population is strongly tied to the amount of animal protein in the diet.[6] Thus, Davis’s heavy consumption of raw milk, eggs, and cheese almost certainly shortened her life. Unfortunately, her books lived on, like landmines in an abandoned battlefield, continuing to provide misleading and sometimes lethal advice about food and nutrition.

Davis couldn’t have honestly claimed that she “didn’t know” about the dangers of animal-based foods. By the late 1950s, Nathan Pritikin had learned, from reading reports of population studies, that rich, fatty foods from animals cause heart disease, and that heart disease could be cured by removing those foods from the diet. Pritikin learned this from his own study of the medical literature. He had no training in dietetics or medicine. If Pritikin could figure this out, why couldn’t Davis?

This naturally raises a question. Why did Davis fill her books with “hogwash” when she had the training and presumably the intelligence to correctly interpret the medical journal articles she was supposedly reading? As a dietitian, and especially as a human being, didn’t she have an ethical duty to tell the truth? What could possibly explain such intellectual dishonesty? Nathan Pritikin was willing to incur the wrath of cardiologists to tell the American people the truth about the role of diet in heart disease. Davis wasn’t afraid to face the wrath of the medical profession. Why didn’t she do so to tell the truth?

The problem is not limited to the works of Adelle Davis. Why are so many nutrition books that are sold to the public filled with such dangerous hogwash? Edward H. Rynearson, MD, who was a retired professor of medicine from the Mayo Clinic, wrote an influential article in 1974 claiming that “Americans love hogwash,” which he defined as “worthless, false or ridiculous speech or writings.” I don’t think that Americans liked Davis’s books because they knew they were “worthless, false, or ridiculous.” They simply had no independent way of evaluating them. They want sensible and practical advice, given in a respectful tone. (They would also like to be told that they can eat as much fatty food as they want, but that’s another issue.) The people who killed or injured their children by following Davis’s advice had no idea that her books were hogwash, and no way of finding it out before it was too late.

Reference List

  1. Adelle Davis’s books on nutrition: Commentary by Edward H. Rynearson, M.D. Med Insight. 1973;32-34.
  2. Wetli CV, Davis JH. Fatal hyperkalemia from accidental overdose of potassium chloride. JAMA. 1978;240(13):1339.
  3. Oseas RS, Phelps DL, Kaplan SA. Near fatal hyperkalemia from a dangerous treatment for colic. Pediatrics. 1982;69(1):117-118.
  4. Potassium metabolism in gastroenteritis. Nutr Rev. 1956;14(10):295-296.
  5. Barrett SB. The Legacy of Adelle Davis. QuackWatch Web site. Available at: http://www.quackwatch.com/04ConsumerEducation/davis.html. Last update: October 13, 2006.
  6. Campbell TC, Campbell, TM. The China Study. Dallas, TX: Benbella Books. 2006.