More Sleep + Less Sugary Soda = Better Heath

OK, with any luck you already know these things, but it always helps to have new research come along to remind us of these truths. The Nation's Health (from the American Public Health Association) summarizes a study published recently in the Proceedings of the National Academy of Science. 

We show that more than one-half of racial differences in cardiometabolic risk can be explained by sleep patterns—namely, less total sleep and lower sleep efficiency among African American than European American adults. Sleep is a malleable health behavior that is linked with characteristics of the social and physical environment and could be an effective target in national efforts to reduce racial health disparities.

Differences in sleep patterns may be attributed to increased exposure to social stresses, the study showed. Stressors associated with socio-economic status and systemic discrimination can lead to low sleep efficiency.

Although the study compared racial/ethnic groups, the lesson is true for everyone--better sleep is associated with better health. You can find out more about this by thumbing through issues of the Journal of Sleep Research--with luck it won't put you to sleep... 

Sugary sodas have been under attack for a long time and the evidence continues to mount that they push your weight up, and that is bad for your health in a variety of ways. The latest research comes from the American Journal of Public Health and uses data from a population of teachers in Mexico.

We followed 11 218 women from the Mexican Teachers’ Cohort from 2006 to 2008. Dietary data were collected using a semiquantitative food frequency questionnaire. Weight was self-reported, and waist circumference was self-measured. We used linear regression to evaluate changes in sugar-sweetened and sugar-free soda consumption in relation to changes in weight and waist circumference, adjusting for lifestyle and other dietary factors.

Decreasing consumption of sugar-sweetened soda was associated with less weight gain, and increasing consumption of sugar-sweetened soda had an opposite association. These results were similar when waist circumference was used as a measure of adiposity. The impact of changes in sugar-sweetened soda intake on weight appeared to be stronger among women who were overweight or obese at baseline relative to women who were of normal weight. Changes in sugar-free soda consumption were not associated with weight change.

Thus, if the consumption of sugary sodas increased over a two-year period, so did a person's weight. Conversely, less sugary soda was associated with a weight loss. The results were not huge, but this was only a two-year timeframe. And the fact that sugar-free sodas had no effect lends credibility to the findings.

So, drink less sugary soda, get more sleep, and, by the way, don't forget to be vaccinated against the flu. 

Chinese Government Doesn't Want Us to Know About the Low Birth Rate

A recent story in the South China Morning Post notes that the latest Statistical Yearbook from China omits mention of the birth rate. Very suspicious!

China’s National Bureau of Statistics has been publishing the data on the “age-specific fertility rate of child­bearing women” – the measure of how many children were born to different age groups – annually since 2004.

But in the 2017, China’s statistics yearbook, which sets out the data from the previous 12 months, the bureau said it had decided to remove these figures, which help to calculate the country’s overall fertility ratio [the total fertility rate, as we would call it].

Almost three years ago, as the one-child policy was being lifted in China, I commented on the fact that demographers did not expect a rise in the birth rate, whereas the Chinese government did. Not surprisingly, the demographers appear to continue to be right.

The statistics agency’s number, which indicated a fertility ratio of 1.05 in 2015, ran counter to an estimated fertility rate of 1.6 from the National Heath and Family Planning Commission, the body that is responsible for China’s family planning policy and ruthlessly implemented the country’s one-child policy for decades. 

While the statistics agency did not explain why it stopped publishing the data, demographers said it underscored the problems with China’s official population figures.

Liang Zhongtang, a demographer who sat on the state family planning commission in the 1980s, said China’s fertility rate had failed to show any meaningful increase after the country officially rolled out a universal two-child policy in 2016, adding that could be one reason for the non-disclosure. “A gap between what the government actually got and what they had expected may persuade them to stop releasing the data,” Liang said.

If the birth rate really is still close to one child per woman, as we expect it really is, the consequences for China's age transition are clear: the aging population will continue to grow more quickly than the younger labor force, and this will create continual strains on the Chinese economy. It is not clear whether or not this feeds into the new "Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era" that is now enshrined in the communist party's constitution. What we do know from the South China Morning Post story is that family planning wasn't mentioned by Xi during the recent communist party gathering. "Instead, Xi used the much milder term “population policy” and stressed that China must “enhance strategic research” into its demographics."

Demographic Effects of Girls' Education in Developing Countries

The National Academies Press just released a synopsis of a workshop organized earlier this year by the Population Committee of the National Academy of Sciences on the topic of "Demographic Effects of Girls' Education in Developing Countries." The workshop was headed up by Ann Blanc of the Population Council, Jere Behrman of the University of Pennsylvania and Cynthia Lloyd who is now an independent consultant but was with the Population Council for many years. The main question raised was this: Why does education have an impact on fertility? In other words, what are the causal linkages?

In general, the participants in the workshop (who were all demographers doing work in the area of girl's education and fertility in developing countries--especially in Africa) concluded that an education can change the way a girl thinks about her place in the world and this can influence her decision-making about the timing of both marriage and childbearing. At the same time, having a baby early almost always truncates a girl's education and sets her back for the rest of her life. So, the causal links work in two directions.

I read through the synopsis of the workshop looking for things I didn't already know, and the major point that was brought out that needs some consideration is the idea that the quality of education may actually be lower now than it used to be in some of the countries that were being discussed. If that is true, then the impact of education on attitudes and behaviors of young women may be less than in the past. Still, however, I saw nothing to suggest I should modify the following summary that you will find on page 207-208 in Chapter 6 of the 12th edition of my text:

It is nearly axiomatic that better-educated women have lower fertility than less-educated women in any given society. It is the identification of this kind of fertility differential that helps to build our understanding of reproductive dynamics in human societies, because it causes us to ask what it is about education that makes reproduction so sensitive to it. In general terms, the answer is that education offers to people (men and women) a view of the world that expands their horizon beyond the boundaries of traditional society and causes them to reassess the value of children and reevaluate the role of women in society. Education also increases the opportunity for social mobility, which, in turn, sharpens the likelihood that people will be in the path of innovative behavior, such as fertility limitation, that they may try themselves. Indeed, the role of education is so important that demographers at the Vienna Institute of Demography have created a whole set of population projections incorporating trends in educational attainment as a predictor of fertility levels.

The Demographics of Not Moving to Where the Jobs Are

There seems to be general agreement that Donald Trump's base of support are people who feel they are being left behind by the process of globalization and they want some change. It seems highly unlikely that Trump's proposed tax cuts will help those people, but this week's Economist takes a stab at the problem. 

The general pattern in the past in most countries of the world has been for people to go where the jobs are. My wife's grandfather migrated from Denmark in the late 19th century because there were no jobs there, but there was a chance to be a successful farmer in the American midwest. In my lifetime, my family certainly moved for economic reasons. During the first 12 years of my life, we lived in two different cities in northern California, three cities in Oregon, and one city in Arizona before settling down in San Diego. But Americans are moving less than they used to, according to Census data assembled by the Economist (see below). 

The Economist suggests that several demographic factors may help to understand this slowing of migration. There are now many more two-earner households, making it harder for couples to move (or even to decide where to move if they are going to move). At the same time, people may have older parents who are aging in place and who expect or at least hope that their children and grandchildren will be close enough to help them out. Another major impediment to movement is the high cost of housing in almost all of the urban places that are home to the superstar companies. The higher wages in those places may be offset by the cost of living there. There is also the fact that many unemployment and welfare benefits are place-specific. If you move, you lose those benefits, thus reducing the incentive to move since most people tend to be risk-averse.

The principal suggestion for change proposed by the Economist amounts to local economic development. This could involve a public-private partnership to invest in new types of businesses where globalization has left a labor force looking for work. Going along with this could be an investment in local community colleges geared toward teaching people the skills that these new companies need for success. This is so crazy it might just work.

How Many Births Were Averted in China by the One-Child Policy?

My thanks to Stuart Gietel-Basten for pointing to a story in Science magazine by Mara Hvistendahl about a controversy brewing over how many births were averted in China by their one-child policy.

A new study of China’s one-child policy is roiling demography, sparking calls for the field’s leading journal to withdraw the paper. The controversy has ignited a debate over scholarly values in a discipline that some say often prioritizes reducing population growth above all else.

Chinese officials have long claimed that the one-child policy—in place from 1980 to 2016—averted some 400 million births, which they say aided global environmental efforts. Scholars, in turn, have contested that number as flawed. But in a paper published in the journal Demography in August, Daniel Goodkind—an analyst at the U.S. Census Bureau in Suitland, Maryland, who published as an independent researcher—argues that the figure may, in fact, have merit.

Now, to be honest, I'm not sure that Goodkind's study is "roiling demography," but the paper is, in fact, written in a somewhat contentious style because it is obvious that Goodkind knows that his analysis will likely be unpopular. To be sure, he notes explicitly that his conclusions are different from those of a lot of people, including Stuart Gietel-Basten, and Mara Hvistendahl who wrote this story for Science. 

If you have read Chapter 6 of my book, you will know from Figure 6.9 (see below) that the drop in fertility was very similar in China (where the one-child policy was implemented in 1979) to that in Taiwan, where there was no such policy. 

The Taiwanese are culturally very similar to those in mainland China and, despite the fact that economic development may have taken off a bit earlier in Taiwan than on the mainland, the two countries were already on the same downward fertility path before China implemented its one-child policy. Goodkind tends to dismiss that argument in his paper, preferring to believe that the differences in economic development were more important than the data seem to suggest. 

My reading of Goodkind's paper is that it is much ado about nothing. While one may question the editors of Demography as to whether it should have been accepted for publication, it at least reminded us that there's nothing to see here folks. The one-child policy was a human rights disaster and, in my view, was not necessary to the drop in fertility in China. The Chinese were going to avert those births with or without that policy.

Can Movies and TV Programs Lower Egypt's Fertility?

Fertility has been going up, not down, in Egypt over the past few years, as I have blogged about twice over the past two years (here and here). A paper just published in Demographic Research by researchers at the Wittgenstein Centre for Demography and Global Human Capital in Vienna analyzes the available data--especially from the Demographic and Health Surveys--and comes to the following conclusion:

We find that well-educated women between 20 and 29 years lack labour market opportunities. They may have preponed their fertility. Fertility could start declining again once the labour market situation for women has improved. On the other hand, the family model of three children is still widespread in the country.

I admit that I have never used the word "prepone", but it is the opposite of "postpone" and it makes sense in this usage. In a footnote in the paper, the authors indicate that the Egyptian government was trying to figure out what to do in order to lower the birth rate. My thanks to Abu Daoud who found a story about one of the things being tried--movies and TV programs.

In announcing the results of Egypt's 2017 census on Sept. 30, President Abdel Fattah al-Sisi also identified major issues surrounding the population that has grown past 100 million: early marriage, insufficient housing and, most important, overpopulation. He said, “We must face these flaws in society in collaboration with civil society and media.” His reference to the media gave newspapers and websites the green light to analyze the potential of the media as well as the film industry in confronting overpopulation in the country.

Overpopulation and problems associated with it, such as higher costs of living and uncontrolled urbanization, have long been on the agenda of the Egyptian cinema, along with issues that are hampering the lowering of birth rates, such as a rejection of birth control.

One of the challenges here is that the government has to back up any influence that the media might have by making family planning programs readily available to couples. And, of course, there has to be recognition that getting women back to work is a key element in lowering fertility. Even in urban areas, fertility remains higher than one might expect. More than a decade ago, my colleagues and I published an article on fertility in Cairo, in which we noted that:

Fertility transitions are historically thought to have started in cities and then spread to the rest of the country. This would suggest that in Egypt we would find that Cairo was well ahead of the rest of the nation in its fertility transition. The data suggest otherwise and highlight the fact that many parts of Cairo are still experiencing high levels of fertility.

There is still a long way to go to lower fertility in Egypt, but the country desperately needs to slow that pace as soon as possible--since it is, among other things, a nation facing potential water scarcity and the dangers associated with that. 

The Demographics of Water Scarcity

Many thanks to the folks at Population Matters for pointing to a report detailing the impact of water scarcity on youth unemployment and migration. The story comes from the International Institute for Sustainable Development and refers to analyses recently undertaken by UNESCO's World Water Assessment Program.

It finds close links between the impacts of water scarcity and migration patterns in regional hotspots including in the African, Mediterranean, South Asian and East Asian regions. The report also shows that water availability and quality impacts both youth employment and social stability.

The publication finds that growing climate variability affects water resources and the availability of jobs for youth, especially in arid and semi-arid regions. While the jobs most affected by water scarcity are in agriculture, other affected sectors include animal husbandry and fisheries. Populations migrate as a way of adapting to the lack of both water and employment opportunities.

The story has a link to a downloadable version of the report, which seems well-researched and referenced. Although it is not emphasized in the report, we know that the underlying problem here is population growth. With respect to Northern Africa, for example, the report highlights the propensity for conflict in places like MENA (see the map below) where water scarcity is combined with rapid population growth:

The figure also shows the hotspots of water-related disputes in the Mediterranean and North Africa (MENA) region, e.g. Jordan River, the control of the water resources of the Golan Heights or of the Litany River (Chazournes et al., 2013). Other conflicts among riparian countries are related to the allocation of the water from the Nile (Veilleux, 2015) and the downstream impacts of the Turkish Southeastern Anatolia Project (GAP) (Hommes et al., 2016). Often, these conflicts are caused by the high and intensive use of water in agriculture (in 2000, amounting to 63-79% of total water usage in North Africa) in a context of endemic water scarcity, which leaves other sectors and household water scarce. Notwithstanding, food security is in peril as population growth – coupled with constantly decreasing water flows since the 1960s – has in fact required an ever growing water usage in agriculture. The current situation is symptomatic of a low-adaptive capacity to climate change (Brauch, 2011).

Keep in mind that people have been thinking about these connections for a long time. In particular, I have mentioned in Chapter 1 of my book, as well as in blog posts, that Thomas Friedman of the NYTimes has linked water scarcity and population growth to the civil war still going on in Syria. 

The Plague is Still Upon Us

Mention of the plague usually brings up mental images of the Black Death (the bubonic plague) in the Middle Ages, the high mortality of which brought important demographic changes to a lot of villages in Europe and elsewhere. But the disease is still walking amongst us, as a story by Reuters today points out.

A probable case of plague in the Seychelles, imported from Madagascar, is believed to have sparked the Indian Ocean country’s first outbreak of the disease, the World Health Organization (WHO) said.

Plague, which is mainly spread by flea-carrying rats, is endemic in Madagascar. A large outbreak has killed 57 people since late August, according to the U.N. agency, the first time the disease has appeared in non-endemic urban areas, including in the capital Antananarivo.

Seychelles health authorities reported a probable case of pneumonic plague on Oct 10 in a 34-year-old man returning from a visit to Madagascar, the WHO said. “The patient continues to be hospitalized in isolation until completion of the antibiotic treatment. He is currently asymptomatic and in stable condition,” the WHO said.

Nearly 70 percent of cases in Madagascar have been pneumonic plague, a form spread human-to-human that is more dangerous than bubonic plague and can trigger epidemics. The pneumonic form invades the lungs, and is treatable with antibiotics. If not treated, it is always fatal and can kill a person within 24 hours.

Most of us have never been either to Madagascar or the Seychelles, but that doesn't mean we are immune to the risk of the plague. The US Centers for Disease Control reports that an average of 7 cases per year are reported each year in this country. Note also that while the bubonic plague is usually transmitted by fleas feeding on infected rats, pneumonic plague can be directly passed from one human to another--no fleas or rats required.

Dan Brown--Novelist and Demographist

I have admitted before that I am a fan of Dan Brown and I always look forward to the release of his books--the latest of which is Origin. When his novel Inferno came out in 2013, I blogged about it because the theme of the book was about the threat of global overpopulation (as I note on page 8 of the 12th Edition). He refers to Malthus as a "demographist" and I had never heard that term until Dan Brown used it. A Google search suggests that it is a synonym for demographer, but I think I am going to be a little more nuanced. A demographer is someone who has an academic background in the field of demography and teaches and/or does research on demographic issues. By contrast, I am going to label as a demographist those who use demographic ideas and information without necessarily having a lot of background in the field of demography. That is not a bad thing; it is just a different thing. 

So, by that definition, Dan Brown is a demographist, along with being a brilliant novelist (and of course it doesn't hurt that his protagonist is a college professor!). His novels take place in real places that he has obviously carefully researched, and with real substantive themes, typically related in some way to religion. I thought about that, in fact, when on page 29 of Origins, Brown describes atheists as "one of the planet's fastest-growing demographics." Based on reports from Pew Research, I'm guessing that this is not an easy statement to fact-check, but the data do seem to suggest that the proportion of people in the U.S. who say they are atheists is growing. The number is larger if you more generally refer to people with "no religion" (which doesn't necessarily mean they don't believe in God). 

Interestingly enough, the "culture clash" between atheists and followers of traditional religions that forms the theme of Origins is taking place in Spain, and much of the action occurs in Barcelona--in Catalonia--a current hotbed of culture clashes, as I recently discussed.

Overall, then, reading Dan Brown novels is another example of how demography underlies everything in the world, whether we realize it or not.

Inside Demography--An Interview with Andrew Cherlin

Dr. Andrew Cherlin is the Benjamin H. Griswold III Professor of Sociology and Public Policy at John Hopkins University, and is a Past President of the Population Association of America (PAA). He is one of the world's foremost family demographers--widely published, cited, and quoted. He has appeared in numerous of my blogs over the years, starting in 2010 and most recently just a couple of weeks ago.

Last April he was interviewed by members of the PAA History Committee (which I chair) during the PAA's annual meeting in Chicago, and we now have this interview available online at the website of the PAA. One of the important themes in Dr. Cherlin's work over the years has been to bridge the gap between academic research and public policy. Here is an excerpt from page 18 of the interview:

The recent development that I see as most productive among policy people is an agreement among conservatives and liberals that both economics and culture make a difference.

In the economic realm, people with college degrees are the winners in our globalized and automated economy. And they’re the ones who have a marriage-based, stable family life these days. What we need to do is help the people who are not the winners, help them by getting them better educated, not necessarily college degrees for all, but community college training and other apprenticeship-based programs. That’s what we need to do.

On the cultural level, I do think there is a role for stressing the importance of stability in family life. And there is nothing wrong with the liberals doing that. So we need to think about both economic and cultural ways to lessen the class divide that in 2017 seems so strong among American families.

In my view, this is the one of, if not the, most important reason for doing demographic research--to improve our understanding of how the world is working, so that we can do our best to improve life for all humans. 

Will Malaria Ever Be Gone From Africa?

Malaria has been one of the biggest killers of humans over the centuries, and an enormous amount of international effort has gone toward eradicating the parasites and the mosquitos that carry the parasite from one victim to another from the earth. The mosquitos (the vectors) flourish especially in warm, wet weather, so it is the mid-latitudes in which malaria is most prevalent, as you can see from the map below:

The most deadly of those parasites is the Plasmodium falciparum, which is prevalent in sub-Saharan Africa. There is probably no researcher in the world who has done more to track and map malaria than Robert Snow at Oxford University, and in the latest issue of Nature, he and his colleagues have traced the spatial spread of malaria across the face of Africa for the past 100 years. Take a look at the map below and see if you can spot a trend:

The change over time is, sadly, not so obvious, as Snow and his colleagues discuss:

The reduction in malaria transmission intensity has not occurred equally between countries or within countries (Fig. 1)[see above], with more substantive declines and ‘shrinking of the map’ occurring at the margins of the historical range of P. falciparum transmission than in the heartland of Africa’s most efficient vector species, Anopheles gambiae sensu stricto and Anopheles coluzzii. This heartland forms a densely populated belt from West Africa through Central Africa toward Mozambique, and represents the most severely impacted area of the contemporary malaria-endemic world: it was ignored after 196017, 18 and risks being ignored today19. Our previous and current armoury of interventions has not eliminated malaria in this part of the world, and there is little indication that it will do so in the foreseeable future.

The take-away here is that we cannot be complacent. There is a lot of work to do to dramatically lower malaria rates in Africa and we cannot stop trying. 

Catalonia is Important to Demographic History

One of the hardest things that humans do everywhere in the world is to get along with people whose culture is different than theirs. Spain has a long history of culture clashes and the most recent is the referendum in Catalonia--in northeastern Spain--to become independent of Spain. The difference between Catalonia (whose regional capital is Barcelona) and the rest of Spain lies at the heart of our current understanding of the demographic transition. On page 85 of the 12th edition, I note that:

In the early 1960s, J. William Leasure, then a graduate student in economics at Princeton [and subsequently a Professor of Economics here at San Diego State University], was writing a doctoral dissertation on the fertility decline in Spain, using data for each of that nation’s 49 provinces. Surprisingly, his thesis revealed that the history of fertility change in Spain was not explained by a simple version of the demographic transition theory. Fertility in Spain declined in contiguous areas that were culturally similar, even though the levels of urbanization and economic development might be different (Leasure 1962). At about the same time, other students began to uncover similarly puzzling historical patterns in European data (Coale 1986). A systematic review of the demographic histories of Europe was thus begun in order to establish exactly how and why the transition occurred. The focus was on the decline in fertility, because it is the most problematic aspect of the classic explanation. These new findings have been used to help revise the theory of the demographic transition.

Those provinces that caught Bill Leasure's eye were especially the ones in Catalonia. Compare the map below of marital fertility rates in 1950 in Spain [from one of Leasure's publications] with the regional linguistic map of Spain [reproduced in a paper by Ron Lesthaeghe and Antonio Lopez-Gay]:

In the Catalan-speaking areas, marital fertility was lower than elsewhere and this was due partly to the fact that urban and rural fertility rates were both low. Elsewhere in Spain the birth rates followed the expected pattern of being higher in rural than in urban areas, but Catalonia was different. This caused demographers at Princeton at the time to rethink their approach to the demographic transition in order to take culture--not just economics--into account. Current demography theory is much more sophisticated (and complex) as a result.

Cereal Production Exceeds Population Growth--For Now...

Max Roser at Oxford does a magnificent job of putting data together to help people understand what's happening in the world, and one of his group's recent blog posts (by Hannah Ritchie) relates changes over time in cereal production to population growth. The tension between population and food was at the heart of Malthusian thinking and, to be frank, if were still back in the late 18th/early 19th century of Malthus's day, we would almost certainly agree with Malthus' view of the world. As I detail in my book, two important things have happened since then: (1) we have figured out how to control both mortality and fertility; and (2) we have figured out how to grow more food on an acre of land. Here's a graph of recent trends (which is interactive if you go there directly):

Cereal production accounts for more than half of the global caloric input (including cereals that are fed to animals that are then slaughtered for human consumption) and its production has increased faster than the population has grown. This is due almost entirely to agricultural intensification (more yield per acre), rather than extensification (we are already farming all of the good land).

Of course, we don't know how long this relationship will last--and that is the critical issue. As Ritchie notes in her blog:

The adoption and success of the Green Revolution has not been consistent across the developing world. Sub-Saharan Africa (SSA) has been a region of particular concern in terms of food security. Despite making significant progress in reducing hunger in recent decades, undernourishment in Sub-Saharan Africa remains the highest in the world (with almost one-in-five people living there defined as undernourished). 

In the chart below we see that SSA’s cereal production has been unable to keep pace with population growth. Despite an increase in cereal output of around 300 percent, per capita output has been declining. Overall, we see much greater emphasis on agricultural expansion in SSA, increasing by 120 percent since 1961—approximately equivalent to the total area of Kenya. Relative to Asia and Latin America, SSA’s improvements in yield have been much more modest (increasing by only 80 percent).

Since Africa has the world's most rapidly growing population, the fact that cereal production is lagging behind population growth is a very poor omen for the future, no matter how rosy the current global situation may seem. We have to stay real about this. 

How Will The Hurricanes Reshape Florida's Demographics? UPDATED

Many thanks to Rubén Rumbaut for pointing me to a story in the NYTimes that ponders what an exodus from Puerto Rico might do for (or to) Florida. The focus of the article is on politics because Puerto Ricans tend to be Democrats while the other major Hispanic group in the state--Cubans--tend to be Republicans.

Every day dozens of Puerto Ricans straggle into the Orlando area, fleeing their homes and lives ravaged by Hurricane Maria. In the months to come, officials here said, that number could surge to more than 100,000.

And those numbers could remake politics in Florida, a state where the last two presidential and governor’s races were decided by roughly one percentage point or less.

There are more than a million Puerto Ricans in Florida, a number that has doubled since 2001, driven largely until now by a faltering economy. But their political powers have evolved slowly in this state, and the wave of potential voters from the island could quickly change that calculus.

The single biggest group of Florida-based Puerto Ricans are in the Orlando area, although there is also a sizable number in Miami. So, this could have a clear impact on local politics and on state politics, and the latter could potentially influence national politics. And, of course, since Puerto Ricans are U.S. citizens, the effect is immediate--they just have to register to vote and their influence will be felt in the next election. 

Note that New York currently has the largest population of Puerto Ricans of any state, with Florida second. However, New York is more solidly Democratic, while Florida is a swing state, so migration to Florida is politically more consequential.

Earlier I suggested the possibility that hurricanes in Florida could discourage the migration of retirees from the north into Florida. The older population in Florida seems to lean slightly more towards Republicans than Democrats, so the changing demography of the older population--were it to happen--could also make at least a small difference in state politics.

UPDATE: CNN just today ran a story with more details about the potential demographic and political impact of the hurricane in Puerto Rico.

In the wish lists of Democratic strategists, one imagines the arrival of tens of thousands of Democratic-leaning voters to Florida, seemingly overnight, ranks pretty high.
Two months after Hurricane Maria made landfall on the island, new data suggests that's exactly what's happened.

Figures on school enrollment provided to CNN from the Florida Department of Education suggest that well over 50,000 Puerto Ricans will have moved to Florida and made it their residence heading into the midterm election next year.

"The demographic change to Florida has the potential to affect Federal and state elections," said Michael McDonald, professor of political science at the University of Florida, who maintains the United States Election Project. When the 2020 Census is released, continued population growth in the areas where Puerto Ricans live will likely mean more districts at the state and Congressional levels are drawn favorably for Democrats, he added.

President Trump and the Republican Party in general may wish they had done more to make Puerto Rico livable after the hurricane...

What are the Health Risks for Puerto Ricans?

The devastation of Puerto Rico from Hurricane Maria has so many dimensions that it is hard to even know where to begin. However, most people are concerned first with their health. There have been heart-warming stories of people stepping in and stepping up to evacuate very sick people to the mainland, and of course a lot of otherwise healthy people are self-evacuating in order to ensure themselves and their family members of food, clean water, and sanitation. Those latter two things are the tricky things for those staying behind because polluted water and lack of toilets and sewage can lead to serious health issues.

The biggest concern for most people is cholera, because it doesn't just give you diarrhea, it can kill you. As a news story this week in Nature points out:

In Yemen, cholera has killed more than 2,000 people and infected nearly 700,000 in the past 5 months alone, eclipsing the post-earthquake outbreak in Haiti. Haiti still battles with the disease 7 years after its reintroduction. Meanwhile, Somalia is experiencing its worst outbreak in five years. South Sudan continues to fight its worst outbreak since it gained independence in 2011. If nothing changes, cholera will continue to claim some 100,000 lives a year and afflict around 3 million people, many of them children.

Now, to be sure, the problem in Haiti was caused by Nepalese soldiers brought in by the UN to help after that country's huge earthquake, as I noted at the time. With any luck, no one in Puerto Rico has cholera and, if not, the island will be spared that disease, but not necessarily spared others.

As Puerto Rico struggles to recover from Hurricane Maria, sanitation is a concern. Fifty-five percent of the island lacks running water, according to the governor's office, and Bloomberg reported that residents are bathing and washing clothes in rivers. Many people are getting water from roadside springs, according to NPR, or hoping their hoarded supplies from before the storm don't run out before tap water is restored.

Even without cholera, if any of these ad hoc water sources become contaminated with feces, it could mean a major public health problem. According to the CDC, diseases such as hepatitis A can spread through contaminated drinking water. So can other diarrheal illnesses, including enteroviruses, Giardia and Campylobacter. Standing water after the hurricane may also become prime breeding ground for mosquitos. Zika virus, which causes mostly mild fever in adults but severe birth defects in developing fetuses, is already found in Puerto Rico and spreads via mosquito bites.

It is going to take a lot more than President Trump tossing paper towels to the crowd to keep Puerto Ricans healthy over the next few months until everything is finally cleaned up and working again. The latest issue of the PRB's World Population Data Sheet shows that life expectancy for females in Puerto Rico before the hurricane was actually slightly higher than on the U.S. mainland--83 years for females (compared to 81 on the mainland), while being just the same for males (76 years in both Puerto Rico and on the mainland). We can anticipate that those figures are likely to suffer this year. 

Guns Are a Public Health Problem in the U.S.

Republican politicians may insist that it is inappropriate to talk about gun control so soon after the mass shooting in Las Vegas, but of course these horrific events remind us that we need to do something--and the sooner the better. The first step is to increase public understanding of how "exceptional" the U.S. is in terms of gun violence. Several people have alerted me to a very good story put together by German Lopez at vox.com. He has assembled an array of information that puts things into context. In the first place, the U.S. has an almost unimaginably higher rate of homicides by firearms per million persons than any other rich country--29.7 compared to the next highest, Switzerland, at 7.7. Why is this so? Well, it's because we have so many guns in civilian hands. Using data from the United Nations, the calculation is that while the U.S. has 4.4 percent of the world's population, it has 42 percent of the world's guns that are in civilian hands. 

When it comes to gun deaths, however, Steven Pinker in his excellent book The Better Angels of our Nature: Why Violence Has Declined reminds us that the U.S. varies considerably by state, and the data from Lopez's reveal the pattern, as can be seen in the graph below.

States with more guns have more gun deaths. One line of thinking would be, of course, that these are more violent states and so people need guns to defend themselves. The research, however, suggests that this is a case of reverse causality. In reality, the more guns are available, the more likely they are to be used to kill someone, including the owner (gun ownership is associated with higher rates of suicide).

When economist Richard Florida took a look at gun deaths and other social indicators, he found that higher populations, more stress, more immigrants, and more mental illness didn’t correlate with more gun deaths. But he did find one telling correlation: States with tighter gun control laws have fewer gun-related deaths. (Read more at Florida’s “The Geography of Gun Deaths.”)

Pew Research Center data referenced in the Vox story also show clearly that the vast majority of Americans favor specific policies to regulate gun ownership. It is past time for Congress to respond to the American public on this. This isn't about taking away guns, but rather about lowering the odds that guns will be used to kill innocent people. This will also help in at least a small way to close the gap between the U.S. and other rich countries on overall life expectancy. We have the highest rate of gun ownership and the lowest life expectancy among rich countries. Coincidence?

KFC Adds To Obesity Woes in Ghana

My thanks to David Rain for pointing me to a very interesting and detailed article in the NYTimes about the success of KFC fast-food outlets in Ghana. Well, really just in the capital city of Accra. David and I and others have been studying the spatial demography of health in Accra for several years (you can find details here), and obesity has been a growing problem as the country increases in per person income and more Western-style grocery stores and fast-food outlets become the sources of food and meals. KFC's fried chicken didn't create the problem, but it isn't helping, either. 

But KFC’s expansion here comes as obesity and related health problems have been surging. Public health officials see fried chicken, french fries and pizza as spurring and intensifying a global obesity epidemic that has hit hard in Ghana — one of 73 countries where obesity has at least doubled since 1980. In that period, Ghana’s obesity rates have surged more than 650 percent, from less than 2 percent of the population to 13.6 percent, according to the Institute for Health Metrics and Evaluation, an independent research center at the University of Washington.

KFC’s presence in Ghana so far is relatively modest but rapidly growing, and it underscores the way fast food can shape palates, habits and waistlines.

Research shows that people who eat more fast food are more likely to gain weight and become obese, and nutrition experts here express deep concern at the prospect of an increasingly heavy and diabetic population, without the medical resources to address a looming health crisis that some say could rival AIDS.

One of the several photos in the article shows the flagship KFC outlet on Oxford Street in the Osu neighborhood of Accra. I remember walking by it shortly after it opened a few years ago and thinking--this is probably not a good thing for the health of the neighborhood. The story indicates that there are now 13 KFC stores in Ghana, with the majority in Accra--which already has the highest obesity levels in the country. I just put together the map below using data from the 2014 Demographic and Health Survey for Ghana. It shows the percentage of adult women who are obese, based on height and weight measurements by the DHS interviewers. Accra leads the way by a wide margin, and the farther away you get from Accra, the lower is the level of obesity.

Will Older People Be The Death of Rich Countries?

I've often mentioned the "prediction" that China will grow old before it gets rich. But an even more pervasive theme in the media is that the rapidly aging population of the richer countries in Europe and North America is on the verge of bringing economic collapse. The concern is especially about the ability and/or willingness of younger people to pay the pensions for the older population, since most pension schemes of governments and businesses are pay-as-you-go plans, not real savings plans. This theme came up yesterday in a blog post from John Mauldin of Mauldin Economics. I regularly read his blog (which was recommended to me several years ago by one of my readers), as do a lot of other people, so we need to pay attention to his ideas, whether we agree with him or not.

Look what we’re trying to do. We think people can spend 35–40 years working and saving, then stop working and go on for another 20–30–40 years at the same comfort level – but with a growing percentage of retirees and a shrinking number of workers paying into the system. I’m sorry, but that’s magical thinking. And it’s not what the original retirement schemes envisioned at all. Their goal was to provide for a relatively small number of elderly people who were unable to work. Life expectancies were such that most workers would not reach that point, or would at least live just a few years beyond retirement.

As I have pointed out in past letters, when Franklin Roosevelt created Social Security for people over 65 years old, US life expectancy was about 56 years. If the retirement age had kept up with the increase in life expectancy, the retirement age in the US would now be 82. Try and sell that to voters.

No, don't try to sell that to anyone, because those numbers are not correct. When Social Security was passed in 1935, life expectancy at birth was 60 for males and 64 for females. However, that is not the number to pay attention to. The issue is how long people live past retirement, since those are the years of "dependency" that create problems for the economy. The Social Security Administration has calculated this for us. When Social Security payments started being made in 1940, the expected years of life after age 65 were 12.7 for males and 14.7 for females. The latest data available from the US Centers for Disease Control show that in 2013 life expectancy at age 65 was 17.9 for males and 20.5 for females. If we follow those numbers, then retirement should be about age 72, instead of 67 (which is the current age at which a person born in 1960 or more recently can receive full Social Security benefits).

And for those of you who want to raise the birth rate to "solve" the problem, remember that children are also dependents for twenty years or more. As I discuss in my book, one of the reasons for the implementation of Social Security in the U.S. was that young people needed jobs and this was one way to get older people out of the labor force to make room for the youngsters. Changes in the age structure are more important determinants of the pension crisis than is increasing longevity. The Social Security Administration reminds us that:

Increases in life expectancy are a factor in the long-range financing of Social Security; but other factors, such as the sheer size of the "baby boom" generation, and the relative proportion of workers to beneficiaries, are larger determinants of Social Security's future financial condition.

I am fully supportive of the current ideas for raising the age at which people can receive retirement benefits. People need to work longer, and they also need to save more. Of course, getting back to an economic environment in which the interest rate on a regular savings account is somewhere higher than zero would likely encourage more of that behavior. Finally, we need for Congress to remember that when there is a surplus in the Social Security Trust Fund, it is a pot of money for future retirees, not a pot of money to be spent right now on whatever you want--as happened, for example, during the Bush administration.