Life Expectancy and Public Health

Life expectancy is a complex statistical measurement, and what is meant by the term, whenever it is discussed in media or in terms of contemporary public health, is Period Life Expectancy; the estimated life expectancy of a contemporary cohort (new babies born in that year), based on a complex arrange of statistical calculations. To summarize it:

First, cohort effect across generations is a possible explanation. Life expectancy has often been (mis)understood as a projected indicator of how long on average people in a specific population may live. But, in fact, life expectancy is calculated using current age-specific mortality rates of the particular year of interest. In other words, it is a cross-sectional indicator of the current health situation of the population.

— The Case of Hong Kong (Hong Kong’s world-leading longevity also, long-story short, breaks all the theories and general patterns seen in longevity around the world)

This is different from individual life expectancy, or calculations of history life expectancy. I have a deep interest in this subject, albeit the somewhat imprecise understanding of a hobbyist, with all the excitable or irritated messiness that brings, rather than tedious familiarity often brought to the table by an expert. Gerontology, demography, public health, aging, life span, these issues all have a very potent draw, and this is true to a lot of people, and there is something fundamentally human about the sense of control but also self-interest in looking at, quite literally, life and death.

The thing about Life expectancy, is that a lot of modern people have a fairly skewed idea of life expectancy, particularly in how useful it is as a single statistical tool for indicating health of a society and the upper lifespans of a society. People feel for instance, that we live much longer today than we did just 100 years ago. In Great Britain in 1890, the average life expectancy for a woman was 44 and 41 for a man, but that is largely a product of very high rates of childhood fatality; when as many as half of the statistical model die before age 21 because of poor sanitation, nutrition and high rates of childhood diseases, it skews said model. In truth, the average person who made it to 21 in 1890, could expect to live another 50 to 60 years, dying on average, just a little younger than our contemporary life expectancies, even with the much poorer state of medicine and the lack of treatment for many commonplace diseases. Similarly, for wealthy Romans and other elites through ancient history, living into one's late 70s or 80s was merely somewhat uncommon, not unheard of. There are a lot of measures about a society’s longevity that are interesting and important to examine beyond life expectancy.

This is an important factor for public health measures and government policy; after all the goal is to increase lifespan and to increase so-termed "healthy life expectancy", the ideal is longer lives with less medical care and fewer health issues in old age, as it is clear that old age illnesses are not inevitable, nor is gradually wasting away for 1 year or 25 years some inexorable biological process of slow, torturous death. This facet, public health, is where, now, the Blue Zone Project and Western Media come in, and where, if I may, I must make a few criticisms. First, the Blue Zones Project is a famous and well-funded project identifying "longevity zones" across the world, isolating key factors of the diet and lifestyle, and promulgating them in media. Blue Zones, even if you haven't heard of them, are an influential label, and the project has numerous partnerships with civic organizations, non-profits, and even corporations. They even have played a role in bringing attention to the well-noted benefits of the Mediterranean diet, and promoted a long. The group does a lot of good work, highlighting the role of urban planning, natural movement, sustainable and healthy diets, and the need for systemic changes to lifestyle and civic infrastructure for the sake of public health.

However, my worry is that the BZP, and many NPOs influenced by it and which play a major role in advising and shaping public policy are too shaped and warped by an antiquated value system, one that romanticizes pastoral or agrarian rural lifestyles and whose public health proposals are almost entirely shaped by studies of rural, under-developed but still quasi-modern communities, rather than trying to search out and emphasize fully modern and developed, mostly urban communities and to highlight public health policies that work on a broader scale. The approach smacks of orientalism; of the romantic, wistful descriptions of disappearing communities of Greek herders and Okinawan fishing villages that have the highest rate of centenarians in the world (or so Blue Zones Project claims), with Yoma Linda California (specifically highlighted by endurance cyclist and National Geographic journalist, Dan Buettner, the Blue Zones Project cofounder, for its longevity), the one exception, and as far as I understand, the Blue Zone there is also explicitly tied to the Seventh Day Adventist community there, which does not smoke or drink alcohol and places a strong emphasis on a healthy, vegetable heavy diet, and also happens to have well-above average income (more on that later). Before I continue, let me emphasize that I don't think anything is wrong in the proscriptions of the Blue Zone Group; they aren't wrong, a lot of the dietary and activity recommendations made are entirely appropriate and do indeed have health benefits. But the issue is that too much of an agenda shines through in the narrowness of the recommendations, in almost preachy, highly limited lines of advice, tied to observations of, again, under-developed agrarian societies.

In addition, it is questionable how accurate some of the claims passed around in public health NPOs and in Western media are accurate. I only know that Okinawa is talked about as this ultra-long lived place of mythically good health. Dan Buettner talks about it (even in 2016 talks), and the BZP talks about it, and any article talking about longevity and public health studies, talks about the case of the amazingly long-lived Okinawa (and its diet of beni-imo, fish, fresh vegetables and small amounts of pork), yet as far as I have studied the issue, Okinawa’s longevity is not so cut and dry. While the Okinawan Centenarian Study found 100 year old Okinawans spent an average 97% of their lives free of any disabilities, and other studies in the 1980s and 1990s found very high life expectancies, particularly in rural Okinawa, Okinawa as a prefecture has not had the highest life expectancy within Japan since the mid 1990s, and now ranks 36th for men, and 7th for women in life expectancy. In particular, life expectancy for men have drooped, and chronic illnesses such as diabetes and heart disease have increased drastically, particularly as the traditional Okinawan diet has gone out of fashion and fast food and more meat heavy diets have taken its place and the islands have become more developed and urban than historically was the case. Meanwhile, mountainous Nagano Prefecture, a spread out prefecture in central Japan where most of the population lives in highly developed mid-sized cities, and which has middling income levels, has had the highest life expectancy in Japan for decades now. It was only in 2015 that Shiga Prefecture narrowly passed up Nagano with a projected life expectancy of 81.78 (after a health initiative project) for men to Nagano’s 81.75, though Nagano's life expectancy for women 87.67 kept it in first place overall. Similarly, in that year, Nagano had the lowest death rates for elderly per 100,000 people of any prefecture for both men and women, ranking last for number of deaths per 100,000 people. Okinawa ranked 27th for women and 17th for men (higher means a higher death rate per 100,000 people). Okinawa also ranks second, behind Akita Prefecture (a rural, economically struggling prefecture in Northwest Japan) for the largest gap in life expectancy between men and women, highlighting the trend that demographers and researchers have noted, wherein nearly all of the decline in Okinawa's exceptional life expectancy can be attributed to skyrocketing mortality rates among men and high rates of smoking, obesity, and heart disease among Okinawan men.

Looking at other common longevity markers tells the same story. Comparing average remaining life expectancy for men, Nagano leads in every age cohort, though there are drastic shifts within the Okinawan data between cohorts. 40 year old Okinawans rank 38th in the nation in the modeling, whereas at 75, Okinawan men rank a narrow 2nd, just .01 years behind Nagano. Okinawan women lead the nation in average remaining life expectancy once you hit 65 years of age, and at 75, they have a pretty clear lead, with 16.51 years of average remain lifespan compared to Nagano in 6th with 16.09 years, a .42 year difference in a statistical table mostly decided by tenths or hundredths of a year. So, there is at least one statistical measurement that bears witness to the aura of longevity attached to Okinawa, and the drastic generational change is clear evidence that as the island has shifted to diets much heavier in meat and fast food, and the typical Okinawan diet is no longer followed, that basic health indexes have suffered. One last index, which the Blue Zones Project places enormous emphasis on, is the number of centenarians per 100,000 people. It is not unfair to characterize Buettner's entire project as being centered about centenarians per 100,000 people, as the origins of the project and the list of chosen, example Blue Zones, as well as media interviews, are all centered around the number of centenarians per 100,000 people. Well, as of 2020 Okinawa ranks 19th among Japan's 47 prefecture level administrative divisions, with 83.6 centenarians per 100,000 people (the U.S. is 30.4, well below Saitama, ranked 47th in Japan with 40.01). Nagano ranks 9th, with 96.24 per 100,000 people. The top two spots are taken by two extremely rural and isolated prefectures, Shimane, and Kochi prefecture, with astounding numbers of 127.6 and 119.77 per capita respectively. So, on the whole, Okinawa as a special case for longevity, which continues to be repeated lock stock and barrel in Western media (particularly in any public health related article that makes international comparisons) is quite dated. There are a few questions I have too, for how accurate the public records on which a lot of the research for Okinawa was conducted from the 1970s into the 1990s, as well as other factors.

There are two concerns I have:

1. Okinawan civil records were mostly destroyed by World War II, and in addition to that, due to a discriminatory citizenship classification system, old records were re-entered into the new Kokuseki system post-war. Unrelated to this, but the world's oldest man ever verified at one point, Shigechiyo Izumi, was 105 when he died, not 120, and the evidence is overwhelming now that his actual claimed age was inaccurate and that his name was a necronym for a dead older brother who had appeared in an earlier census record.

2. I think the bigger source of potential error is the massive depopulation of Okinawa due to outward migration in the fifty years prior to WWII, and the massive, tragic civilian casualties of World War II. As a percentage of the total civilian population, you would be hard pressed to find any region more devastated than Okinawa. This in addition to the prior high out-migration, left the prefecture with 2-3 generations of residents with substantially more women than men (women live longer than men, so this would affect the overall life expectancy projections of the prefecture), as well as other potential effects (people with weaker health died at very high rates in the war, the out migration opened up more land/reduced overcrowding and thus actually improved nutrition for those remaining in the area during the war and in the post-war period). There are chances the data for older Okinawans has been skewed or made unrepresentative in ways that have slightly or greatly exaggerated longevity, and now that the data has been more normalized and standardized, a natural corrective has come about. This would explain why Okinawa is virtually the only region of Japan to have seen a downward trend or stagnation of its life expectancy the past thirty years. While this may seem ambiguous, I find it no less ambiguous nor any less a cop out than claiming that the noticeable decline in Okinawan life expectancy, and mainly Okinawa (and not the rest of Japan) the last 30 years is due to the vague concept of "westernization" (specifically there is a rather steep drop in the statistical rankings for cohorts born after 1940 as opposed to before it).

On the contrary, Nagano Prefecture is fascinating because of the opposite factors at play. In the 1960s it ranked near the bottom of the nation in life expectancy, and only an extremely aggressive mobilization of public resources changed that. In the 1980s the Prefectural government spearheaded a massive ad campaign requesting people cut down the salt used in traditional pickling and using less miso in soup and only having miso soup once a day, instead of with every meal, going after the prefecture's nation-leading, massive salt intake (I have heard that average  intake was over 6 grams of salt per day) that was leading to high rates of cerebral diseases like stroke. In addition, the government pushed people to eat salads and fresh vegetables, rather than the prefecture’s traditional diet, wherein heaping bowls of pickled vegetables such as Nozawana, cabbage, daikon, and others were eaten, as a result of the lack of refrigeration and the long cold winters. And, perhaps surprisingly by American standards (where requests to avoid unnecessary travel and wear a mask during a pandemic invoke mass backlash and rage) the intervention worked. Nagano also, starting in the mid-1960s, mobilized and expanded public health programs, with more than 10,000 people working in professional and volunteer positions educating residents on diet, healthy habits, starting fitness programs for elderly, organizing community farms, and so on. The prefecture also leads the nation in numbers of community centers (social connectedness), and emphasizes both social activities for seniors (a major part of Blue Zones Project recommendations), and eating lots of vegetables (leading the nation in daily vegetable consumption).

What it doesn't have are lots of tuber consumption, or eating beans (other than tofu) or eating lots of fish (Nagano is landlocked and fish feature less prominently in local diets than most of Japan), all central parts of the Mediterranean diet and the Blue Zone Project’s personal dietary recommendations. There is also, from my own observations, a bit more red meat consumption in the prefecture than you would see in the typical Japanese diet, and fast food is certainly present everywhere; I live a mile from a KFC and a McDonalds, as well as several Japanese fast food places. It is the very fact that Nagano, a middling income, developed prefecture with fast food and junk food stocked supermarkets and a modernized, Westernized economic and social system, in a region with long, bitterly cold winters, has a stellar life expectancy and scores higher than Okinawa in almost every statistic. Nagano proposed simple solutions to fix chronic health problems; educating the public on general recommendations about eating fresh vegetables and cutting down on salt, far less than the at-times draconian sounding and specific, detailed Mediterranean diet recommendations of the Blue Zones Project. Nagano also focused on some investments that such holistic approaches seem to thumb their nose at (like increasing medical access, reducing medical costs for doctor's visits, promoting preventative medicine) and other initiatives that pretty much anyone involved in public health promotes: using government funded outdoors initiatives to encourage people to patron hot springs, and to hike, set up community gardens, form community walking groups and so on, all to encourage people socialization and exercise.

How Nagano Became Japan's Longest-Lived Prefecture, Nagano Public Health Policy

Nagano also ranks first in Japan in Healthy Life Expectancy and first in Japan for the least amount of time the average person spends in the hospital, which is embodied in its health slogan pin pin korori, which is basically a catchy shorthand for live spry and energetic and die quickly (as morbid as that may seem, Japanese people are very open and frank about human mortality and surprisingly calm and nonplussed about the idea of their own mortality). The prefecture with the longest lives, and one of the highest rates of residents over 65 in the country also has some of the lowest per capita medical expenses in the country, which kind of explodes the dystopian antigovernmental warnings of pessimists who say aging populations are going to require rampant medical care and crushing medical expenses. This comes in an unexpected region; namely a landlocked prefecture with long, bitter cold winters and sweltering hot summers, as well as a below average per capita income ranking 22nd in the country at 36,289 dollars per capita. To say nothing of the heavy drinking culture and the high rates of smoking, despite which the prefecture has world-class numbers in health and longevity indicators. Nagano is just a sterling example of public health initiatives based on general nutrition advice and the promotion of outdoor activities can have drastic impacts on life expectancy and public health in just a few decades. There seem to be other factors too; Nagano leads Japan in % of 65+ year olds who are employed (part time or otherwise) and there is a strong correlation between early retirement and early mortality, as well as being the only prefecture 100% in compliance with strict clean air requirements throughout the year. Nagano's green living movement, and the cleanness of its air and water and the strong local food network, all contribute to its longevity.

It is also worth noting that Shiga Prefecture in 2015 narrowly passed Nagano in projected life expectancy for men (we do not have 2020 numbers), but only after an extensive public health initiative and project that brought Shiga from the middle of the pack nationally to number 1 (and sparked a new bragging/marketing rights rivalry between the two prefectures). I would like to see more discussion of Nagano in Western media, more discussion of Nagano and Shiga prefectures when bringing up public health and longevity on a broad regional scale, and on how partially westernized diets and western style economic configurations can coexist just fine with long life expectancies and healthy life expectancy.

On a side note, the longest lived municipalities (a much smaller regional division) in Japan are all rich suburbs, with a few exceptions mostly in rural Okinawa and in Nagano (rural Okinawa still has many of the top life expectancies for women in the country). The longest lived governmental division in the world is the relatively wealthy, urban Hong Kong (which completely obliterates all of the dietary and lifestyle recommendations of the Blue Zones Project and most public health research), for men it is Switzerland, one of the wealthiest countries in the world. In America, the three longest lived counties are in order, Summit, Pitkin, and Eagle Counties, all in Colorado's ski country (Pitkin most Americans might know for Aspen), and all very rich compared to the country as a whole, noted for their health food craze and healthy living cultures, and with ample opportunities for outdoor sports in a region where very low levels of air and water pollution. Needless to say these areas are much healthier than America as a whole. Summit County (Breckenridge), has an astounding Life Expectancy of 86.83 years in net, with a very small gap between men (85.5 years) and women (88 years), both of which easily top even Hong Kong. The correlation between wealth and longer lives and better health is extremely strong, and just emphasizes the need to study how poorer and middling income areas have raised life expectancy and dealt with public health pandemics like extreme obesity, heart disease, high blood pressure, and so on.

To circle back around, I think Blue Zones does good work. The Blue Zones led initiative in Albert Lea, a poor meatpacking town in South Minnesota was an enormous success and shows the need for real, large scale systematic engagement in public health, particularly in poor and blue collar communities. (https://www.ruralhealthinfo.org/project-examples/812) The indications are clear that even poorer, low-density blue collar areas with low levels of college education attainment benefit massively from public health initiatives that engage the community and integrate broad swaths of said community as well as modest outside resources into health development, i.e. community walking/biking groups, wreck centers, health & diet education, anti-tobacco initiatives, and grocery store reforms (including pre-arranged healthy food sets, and an emphasis on fresh ingredients). These kinds of projects save enormous amounts of money in healthcare services (as well as reducing lost productivity) and improve overall health metrics quickly.

The only fault I find with it, is with the limited data pool (and it's old-fashioned preoccupation with the kinds of pre-modern, traditional agrarian societies). From an academic perspective (I got my MA in Anthropology, so this does verge on the kinds of research I undertook in higher education), this kind of bias is problematic (I got grilled for much more subtle biases in setting up my thesis and defending it). Buettner's book was published in 2015, and still makes particular note of Okinawan longevity (all the data I cited was publicly available Japanese government provided data released in 2015), and has outdated info on centenarian rates per 100,000 people, average life expectancy, healthy life expectancy, you name it, on Japan and also other sites included in the study, such as Sardinia. And the website suggestions are far too tailored towards a narrow model, particularly a narrow model at that. This is an example of good public health models being spearheaded without a broad enough or informed model, and I think an expanded study of long-lived and healthy regions and the environmental, social, cultural, and government policies that structure them, would provide more valuable insights and make for better and more customizable public health initiatives from groups like the Blue Zones Project going forward. Because I think such NPOs can simplify the dietary recommendations much more, and that, honestly, the biggest factors to reducing health issues and expanding lifespan are probably food freshness, bacterial biome of the food, food variety, and most of all, staying active in healthy, smart ways throughout one’s life, rather than very specific and often onerous dietary recommendations (the only one that has a strong scientific basis is the suggestion to reduce red meat in the diet).

Why Should We Be Talking about Longevity measurements and Public Health Policy?

I headlined this sentence, in my final statements, to state probably, the thoughts of the (few?) who will read this, and to it, my answer is: We don’t talk enough about Public Health Policy and Longevity.

Longevity, specifically, “healthy life expectancy”, the concentrations of chronic diseases, and governmental public health policy are all a huge and necessary part of fixing the health care system, just as achieving some form of universal health coverage and driving premiums down (I lean towards setting up a MfA style program long-term, over the course of many years, but there are many other fixes and short-term goals along the way, such as the medicare buy-in, and changing the law to allow medicare to negotiate prices down). I think this requires a discussion of lifestyle and dietary issues, food regulations, and indeed, the manner which cheap and often poorly regulated capitalism has shaped American foodways, specifically away from fresher foods, and towards non-fresh frozen, canned or otherwise heavily processed goods high in salts and other preservatives (anti-molding agents, anti-bacterial agents, etc), in favor of a system built around gigantic outlet store style shopping centers whose main concern is shelf-life and price. Food deserts in many urban, particularly minority areas, the perverse tendency of supermarkets in very poor areas with high density populations but without much car ownership to be the most expensive in town (I have tested this in Louisiana in many places, from Lafayette to Monroe and in New Orleans). An overall lack of government involvement in health education, weak regulation of food additives and heavy subsidies/hesitance to regulate unhealthy industrial practices (and on this one issue, plenty of Democrats are implicated as badly as Republicans), has left American people startlingly illiterate about the most basic health knowledge. 

Public health policy in America is a mess, and the numbers of American suffering from preventable chronic diseases (and at increasingly young ages) is exploding. Hypertension, Heart Disease, High Cholesterol, Type Two Diabetes, Strokes, even some forms of cancer risk seem to rise with poor diet and exercise. Japan is a much older society than America, and despite it’s aging society, health costs per capita are largely controlled and quiet low.