Let me answer your questions.
How popular is paleo and what are signs it’s growing in popularity?
If you go to Google Trends (http://www.google.com/trends/?q=paleo+diet) and type in Paleo Diet, you can see that the concept has grown exponentially in popularity in the past 2-3 years. I dont have exact numbers about how many people worldwide are currently following one form or another of The Paleo Diet, but based upon my book sales, website hits and the explosion of other websites, blogs and popular diet books devoted to this concept, I would estimate the number is now in the millions.
How did it get popularized? By your book? And other ways?
The basic concept dates back to 1985 and stems from a scientific paper called “Paleolithic Nutrition” published in the New England Journal of Medicine by my mentor, Boyd Eaton, M.D. Over the course of the next 17 years, I joined with Boyd and other scientists worldwide to research and write about this concept in the scientific and medical literature. All of my scientific papers on the topic can be downloaded as free PDF files at my website: thepaleodiet.com. In 2000, my wife, Lorrie convinced me to write a popular book on the topic, and in 2002, my first book, The Paleo Diet, was published. It sold well, but certainly didnt obtain the worldwide notoriety that anything “Paleo” now commands. My second book, The Paleo Diet for Athletes (co-authored with the US Olympic Triathlete coach, Joe Friel) also sold well when it was published in 2005, but mainly to a niche clientel of endurance athletes and triathletes. In the next 2-3 years, the nationwide CrossFit, fitness movement began to emerge, and many of the Gyms around the country adopted “Paleo” as their defacto diet, mainly because of Robb Wolf and his highly popular website http://www.robbwolf.com/. Robb is a former graduate student of mine who went on to write the NY Times bestselling, Paleo Solution, which obviously has contributed to the worldwide popularity of all things Paleo. Additionally, the medical community has taken a strong interest in the therapeutic effects of Paleo Diets in their patients for a wide variety of illnesses and maladies.
What is it about the paleo lifestyle that is so healthy?
Contemporary Paleo diets based upon the food groups (meats, seafood, fresh fruits, vegetables and nuts) our ancestors ate are more nutrient (vitamin, mineral, phytochemicals) dense than virtually any other contemporary diet because this lifetime way of eating excludes processed foods, grains, dairy products and legumes. 70% of the calories in the typical US diet come from refined sugars, cereal grains, refined vegetable oils and dairy. The replacement of these foods with grass produced animal foods, seafoods and fresh fruits and vegetables not only increases the micronutrient (vitamins, minerals, phytochemicals) content of the diet, but it also reduces the glycemic load and increases the protein intake, the two most important dietary factors known to promote weight loss and to keep the weight off. Contemporary Paleo diets are high in omega 3 fats, soluble fiber and low in sodium — nutritional factors that have numerous therapeutic health effects too numerous to list here.
What do you say to skeptics who say a broader diet with grains, dairy and beans would be better? Or even just replacing some of the meat with protein rich beans?
As I mentioned earlier, the inclusion of grains, dairy and beans into western diets will automatically reduce the vitamin and mineral density of the diet because these foods are nutritional lightweights compared to fresh vegetables, fruits, grass produced or free ranging meats and seafood. Our research group has pointed out this obvious fact time and again in the scientific literature, and your readers are welcome to view these peer review scientific publications at my website. Beans are not protein rich. In my new book, The Paleo Answer, I devote an entire chapter to nutritional hazards of beans and legumes. Let’s contrast the average protein content in 100 grams of 8 commonly consumed beans and legumes (6.9 grams) to lean turkey and chicken (20.1 grams), 20 common fish and seafood (17.9 grams) and lean beef and pork (17.8). You are starting to get the picture. What makes matters worse is that not just the protein quanity in beans is low, but also the quality in beans is inferior compared to meat and seafood. The FAO/WHO of the United Nations has devised a protein quality index known as PDCAAS and shows that the protein quality of beans are 20 to 25 % lower than animal proteins because of their poor amino acid composition and their high antinutrient content which impairs intestinal absorption. So I say to skeptics, read the scientific literature carefully and let the data speak for itself before you open your mouth.
Some people follow it more strictly than others, correct?
Yes, Paleo has become a movement upon itself with no single version.
Do many – even the majority — people follow the 80/20 rule or not?
I have no data to know the answer to this question one way or another. We live in the 21st century and not the Stone Age, hence the 85:15 rule allows people the flexibility to eat 3 “open” meals per week. Behaviorally, people are much more likely to stay compliant with the diet if a little ‘cheating’ is permitted.
I think I understand the basics of paleo such as meat, seafood, vegetables, fruit, seeds and nuts (not peanuts).
But I am unclear on things like soda. Is that considered a “poison?” and also about the emphasis on making sure you get good sleep.
Obviously soda should not be a staple on the Paleo Diet because it is a concentrated source of either high fructose corn syrup or sucrose, both of which cause adverse health effects if they are consumed regularly. In my most recent book, The Paleo Answer, I devote part of a chapter to showing how even artificially sweetened soft drinks promote weight gain in animals and humans — a surprising development since they were designed to do exactly the opposite.
In regards to sleep, most people report that insomnia becomes a thing of the past when they adopt Paleo. An obscure scientific study has demonstrated that low salt diets (The Paleo Diet is a no salt diet) remarkably improves sleep.
Find my book, read it, accumulate the scientific data and give it 2 weeks. Your health will improve.
Loren Cordain, Ph.D., Professor Emeritus