The Paleo Diet has been at the forefront of healthy eating habits since 2002, when awareness of human ancestral eating practices was unearthed by Dr. Loren Cordain, Ph.D., in his book, “The Paleo Diet.” A New York Times best seller, the wildly popular book was the culmination of the Colorado State University health and exercise science professor’s years of scientific analysis of the range of foods humans ate before societies adopted an agrarian lifestyle.
Without modern technology as diverse as agriculture and air travel, human ancestors sourced food by hunting and gathering naturally occurring plant and animal resources. More than a diet plan, Cordain’s studies uncovered the basic biology that encompasses human nutrition.
In a nutshell, the concept includes foods beneficial to health:
- grass-fed lean meats (beef, lamb, bison, and wild game), fish and seafood
- fresh fruits and non-starchy vegetables
- nuts and seeds
- oils like olive, walnut, flax seed, avocado and coconut
The Paleo lifestyle discourages eating cereals and whole grains, legumes, dairy, refined sugar, potatoes, processed foods and refined vegetable oils like canola, among others. And salt is heavily discouraged.
Cordain said there was never an “aha moment” for developing the hypothesis. If anything, it was a concerted effort of compiling information, stemming from his interest in a 1985 article in the New England Journal of Medicine, “Paleolithic Nutrition,” published by Dr. S. Boyd Eaton, a practicing radiologist and adjunct associate professor of anthropology at Emory University. Cordain read Boyd’s article in 1987.
“In those days, you went to the library, had to look up the article, and that entailed going to the card catalog, finding where the journal was located in the library,” Cordain said. “You pulled out a physical book and thumbed through it to find the article in the bound volume. Then, you Xeroxed it at a cost of $0.10 or $0.25 a page. You can do this instantaneously online today.
“The paper had about 70 or so cross-references. I collected all those articles, Xeroxed those, read them. And unlike today, after I collected all those articles, you didn’t have electronic files, it was a file cabinet. But my initial, self-evident takeaway was that Paleolithic people didn’t eat cereal grains or dairy.”
Cordain recalled it started out with one manila file folder, growing to 100, a thousand, then 10,000 folders.
“I finally got up the nerve to call Dr. Eaton at Emory, and we talked for an hour over his lunch break,” he said. “And Eaton told me, ‘You know more about this than I do.’”
Eaton was well-connected in the medical scientific community and put Cordain in touch with Dr. Artemis Simopoulos, an endocrinologist studying fatty acids and lipids. She was running a huge convention in Greece. Simopoulos invited Cordain to Athens for the conference, and Cordain — who had never been out of the country and didn’t even have a U.S. passport, jumped out of the file folders and into the frying pan.
He made the acquaintance of contemporary leaders in scientific nutritional thought including Dr. Alexander Leaf, a professor at Harvard, with whom he shared a bus seat as the scientists toured Greece over a two-week span.
“We got to talking about my paper, ‘Cereal Grains: Humanity’s Double-Edged Sword,’ and Simopoulos offered to publish it in her journal,” Cordain said. “At the time, I didn’t realize that you don’t write 50-page scientific articles with 400 citations. But in 1997, she published it. I suddenly went from running in small circles at CSU to running in national levels and networking with others around the world.”
About that time, Cordain’s wife Lorrie suggested that, since no one reads scientific journals, he should write a popular book. Connections helped him find Hannah Taub, a New York literary agent, who assisted with the proposal, hooking him up with literary giant, editor Tom Miller — also the editor for Pulitzer Prize winning author Jared Diamond.
“The Paleo Diet,” published in 2002, sold around 10,000 copies.
“It did fairly well,” Cordain noted, “percolating until 2007, and then with the advent of Google and the internet, it went viral. Tom Miller said he’d never seen anything like it. ‘Most diet books are like dwarf stars and burn out. Yours was the exact opposite,’” Cordain recalled his editor saying.
Cordain continued to write scientific papers on his theory, preferring research over writing popular books. He has authored more than 100 peer-reviewed scientific articles and abstracts. There are about 30 randomized controlled trials analyzing the diets of peoples who only used Stone Age tools. Cordain believes the studies have changed the world.
Using information derived from scientific studies beginning around 1915, he and others evaluated the characteristics and lifestyles of contemporary societies like the Inuits — indigenous peoples living in the Arctic regions of North America — who had cultures and food habits similar to those of hunter-gatherer humans living 10,000 years ago. From there, historical records of events occurring during these contemporary people’s lives were compared with world history events. Blood analyses helped chart medical data, combining to create interesting vignettes of cultures — that of people living in modern times with stone age cultural practices.
The studies found a helpful range of values showing similarities between the representative lifespan of Paleolithic peoples and their modern day “Stone Age” counterparts.
“If our ancestors made it through childbirth and childhood mortality, it looks like they made it to their 70s, 80s and beyond,” Cordain said.
Two elements repeatedly stood out in Cordain’s research as he went backward in time — the lack of salt and the increased amount of potassium in the Stone Age diet.
“There was a time when we didn’t salt our food,” Cordain said. “As life evolved, around 3.8 billion years ago a bi-lipid membrane, or layer of fatty acids surrounding all cells, was created. It kept the sea water out and kept the good things, like potassium, in. As life went from a primitive chemical operation, it developed this enzymatic mechanism called the ATPase pump. Evolution is very conservative, keeping things that work indefinitely. This can be applied to plants, animals and bacteria alike. As humans evolved, we developed agriculture, allowing us to eat anything we wanted — including developing a taste for salt. Unfortunately, salt impairs the sodium potassium ATPase pump.”
Cordain and other scientists maintain that excess dietary salt plays a part in modern day diseases such as cancer, hypertension and cardiovascular disease.
“The bottom line is that a mountain lion or a deer doesn’t have to worry about what it eats,” he said. “The animal is genetically adapted to eating what it should. Humans are the one species that don’t eat the foods we’re genetically adapted to eat. You have to believe in evolution.”