Blue zones: right or wrong?

[mccoy]

All of you guys know well the blue zones concept, as later made public by Dave Buettner.

The more I think about it, the more it seems that the real common, governing  factor is genetic variations, not diet and lifestyle (although the latter sure contribute).

• The okinawans followed an unbalanced diet, pooro in protein, poor in micronutrients, too high in carbohydrates.
• The Sardinian shepherds from Ogliastra followed an hypercaloric, hyperproteic, hyperglycemic diet, with lots of saturated fats from dairy products. No fish at all. 
• The Costaricans from Nicoya, an hyperglycemic diet similar to the Sardinians, with little fish, with eggs and meat, more legumes and fruit than the Sardinians
• The Greeks from Ikaria: I don't have a scientific input, mainly a generic Mediterranean diet with a little fish, dairy products, meat.
• The adventists: contrary to the above, they are presently living into a fast-paced society. They follow different diets, with various degrees of adherence to a vegan plan.

I've not found clear statistics of how longer the above populations lived, the info is more qualitative and is restricted to the older individuals who started practicing a traditional diet but who, in many cases, adopted a transitional (less traditional) diet later on. So we don't know if it is better in later years to change diet. The adventists have been studied as far as death and various hazard ratios go, with mixed results (the pescovegan diet of Adventists) but I don't know about longevity.

My bottom line: maybe the importance of diet and lifestyle in the blue ones is overblown. Many diets have not the characteristics which we would associate to significantly enhanced longevity. The more I delve into the issue, the more it seems that genetic variants make up maybe 90% of the reasons why such populations are more longeve. Exception done for the adventists, for whom we don't have clear longevity statistics, AFAIK.

[corybroo]

Thanks for prompting me to do a google search for “twin studies longevity”.  The top of the list was this article Live Long and Proper: Genetic Factors Associated with Increased Longevity Identified  dated July 2010, so a decade old.

Twin studies, however, suggest genetics only account for approximately 20 to 30 percent of an individual's chance of surviving to age 85.   [Yes, that’s survival to 85 as opposed to longevity.  Or as often said here, squaring the curve.   CB]

Lifestyle choices, particularly diet, exercise and smoking habits, play an undisputed role in determining not only how long one will live, but also how well one ages. 

research suggests that exceptional longevity (EL)—living one to three decades beyond the average U.S. life span of approximately 80 years—runs strongly in families.

model [comprising 150 SNPs] successfully predicted exceptional longevity in a different sample of centenarians (individuals that live to age 100) with 77 percent accuracy.

based on subjects' genetic profiles, the centenarians could be further divided into 19 subgroups, some of which were associated with delayed onset of age-related diseases 

90 percent of centenarians are disability-free at the age of 93

[Do the math on the following:  How many people live for a century vs how many have the genetic signature saying it’s possible]

In industrialized nations approximately one out of every 6,000 people lives beyond the age of 100. Supercentenarians, or individuals that are older than 110, are even rarer—only one in seven million fall into this category.

researchers found that approximately 15 percent of control subjects also had the genetic signature associated with longevity. This suggests that many more people have the genetic potential to survive into old age than previously thought.