This is a post about the Blue zones, because I get asked about the blue zone data all the time! On the surface, a lot of the dietary approaches I promote seem contrary to what the blue zone data say about longevity and health. However, when we look under the surface, we see a lot of problematic assumptions and research methods underlying the blue zone data. Let’s talk about it one point at a time.
First of all, the original research and author of the blue zone book, Dan Buettner, left on his research trips with a clear agenda in mind. He believed already that vegetarian diets were both the healthiest and most environmentally friendly diets, and he went looking to find evidence of this. While we all have our biases, I think it is our duty to always be aware of them, and to approach our research with the potential that we could be wrong and need to adjust our beliefs. I’ve shifted my perspective many times over the course of my career and I’m sure I will again!
To be clear, this post is not to rag on Dan Buettner. I’ve heard him interviewed and read his work many times, and he has a lot of important things to say. I believe he is a well meaning person. But his ideas are not supported by other people who have tried to replicate his research, and don’t add up from an ancestral and anthroplogical perspective.
Problem 1: Cherry picking. Dan Buettner picks a few cultures to highlight who both are long lived and include more plant foods in their diet. He ignores many long lived cultures such as people in Hong Kong, Swiss, Icelandic, French, and others, who have long life spans and eat a lot of meat.
Problem 2: Misrepresenting the data. Dan Buettner notoriously did not clarify the difference between “beef” and “red meat” in his surveys. Therefore, people frequently eating lamb and goat (which is many of the cultures in the blue zones) were said to not eat red meat. The mountainous regions many of these people live in are not suited for cows. He also did not ask about dairy at all, and many of the cultures he visited, such as Ikaria in Greece, eat a large amount of cheese and yogurt. Lastly, he visited most of these cultures in the spring and summer, when animal food consumption is naturally at its lowest due to seasonality of plant foods. Some places, he even visited during Lent, which is a time of religious pescatarian or vegetarian fasting for many, and is not representative of the usual diet!
Problem 3: Discrepencies. Many other researchers, from Weston A. Price to Dr. Bill Schindler to nutritionist Mary Ruddick and countless anthropologists, have been to many places that Dan Buettner visited and had very different experiences than he reported. For example, in Costa Rica, they do often eat rice and beans as Dan Buettner reports, but always with pork, chicken, and cooking things in a large amount of animal fat such as lard. Why was this left out in Dan Buettner’s writings? Nose to tail is the traditional way- most traditional menus include things like tail, tongue, ears, feet, head and organs. This helps the animal foods last longer and provides profound nutrition.
The most important things I think we can take from Dan Buettner’s observations are actually the non nutritional ones. He’s not a nutritionist, and so was really not qualified for that kind of research anyway. But he has some excellent messages about the important of movement, community, connection, and laughter. Every community he studied had these factors in common. Everyone walked long distances and carried heavy loads, often up hills or stairs, daily and into old age. Everyone felt a sense of belonging in their communities and have a large network of friends and family. This is what makes up for at least 50% of our health outcomes, and needs to be acknowledged. I appreciate Dan Buettner’s emphasize on this fact.
I want to make one last point about many epidemiological studies, which are survey based studies, that make claims about the health outcomes related to eating certain foods. Many people will point to studies that claim “saturated fat” and “red meat” are associated with various diseases, and “plant based diets” are associated with better health outcomes and longevity. But these studies as I said, are survey based, meaning they do not control for any extraneous factors. Meaning that many people eating plant based diets in the western world are more likely to be affluent, exercise regularly, meditate, and not eat fast food or soda, because they have heard of Dan Buettner and the blue zone data! I think it is more likely that their health outcomes are due to eliminating processed food and living a generally healthy diet, not necessarily a plant based diet. On the contrary, many people answering these surveys who eat red meat and saturated fat regularly are consuming a lot of processed meats from TV dinners, fast food, and convenience store meals, are lower income, and have high levels of stress. It does not take a lot of intelligence to see that a whole foods diet that includes decent quality beef is very different from the diets people answering these surveys are eating- plus all the other lifestyle factors are ignored.
Okay- one more last point. EVEN if Dan Buettner is correct- which I don’t think he is- should we really be fetishizing longevity the way we do? After all, quality is better than quantity. I for one, would rather live to 65 or 70 but be in excellent health and have energy, virility and vitality, than live to 90 or 100 and have spent my life not feeling my absolute best, even if my blood work looks good! There is some evidence to back up this concept, which is summarized nicely in the book 100 million years of food. In this book, studies are quoted that show that high animal food diets early in life lead to high neurotransmitter and sex hormone production, but slightly lower longevity markers. That means a slightly shorter life, but better quality of life. Animal food restriction can lead to longer lives, but usually with low fertility markers. That means the body is not feeling it’s best, but life may be prolonged. I don’t think this is going to be true across the board. But it is interesting to think about. Given these choices, what would you pick?
