The chances to reach extreme old age are much lower than previously thought, new research shows. Research just published by a team of demographers at the social science research organization NORC at the University of Chicago contradicts a long-held belief that the mortality rate of Americans flattens out above age 80.

It also explains why there are only half as many people in the U.S. age 100 and above than the Census Bureau predicted there would be as recently as six years ago.

The research is based on a new way of accurately measuring mortality of Americans who are 80 years of age and older, an issue that has proven remarkably elusive in the past. The work will be significant in arriving at more accurate cost projections for programs such as Social Security and Medicare, which are based in part on mortality rates.

The research, done by Leonid A. Gavrilov and Natalia S. Gavrilova, and published in the current edition of the North American Actuarial Journal, is based on highly accurate information about the date of birth and the date of death of more than nine million Americans born between 1875 and 1895.

The data is publicly available in the Social Security Administration Death Master File. “It is a remarkable resource that allowed us to build what is called an extinct birth cohort that corrects or explains a number of misunderstandings about the mortality rate of our oldest citizens,” said Leonid Gavrilov.

A stark example of the problem of estimating the number of people over 100 came recently when the U.S. Census Bureau revised sharply downward the number of living centenarians. Six years ago, the bureau predicted that by 2010 there would be 114,000 people age 100 or older. The actual number turned out to be 53,364. The projection was wrong by a factor of two.

The newly published paper, titled “Mortality Measurement at Advanced Ages: A Study of the Social Security Administration Death Master File,” explains the discrepancy and is likely to make a difference in the way mortality projections for the very old are done in the future.

The key finding is straightforward—the rate of mortality growth with age of the oldest Americans is the same as that for those who are younger. The research reveals that mortality deceleration, the long-held belief that the mortality rate flattens out above age 80, does not take place.

Anne Zissu, chair of the Department of Business NYC College of Technology/CUNY, said the research provides “an essential tool” for developing models on seniors’ financial assets.

Zissu said the research “will alter our financial approach to this valuation of mortality/longevity risk. Demographers and financiers need to work on this issue together, and their models must adapt to each other.”

The mortality rate for people between the ages of 30 and 80 follows what is called the Gompertz Law, named for its founder, Benjamin Gompertz, who observed in 1825 that a person’s risk of death in a given year doubles every eight years of age. It is a phenomenon that holds up across nations and over time and is an important part of the foundation of actuarial science.

For approximately 70 years, demographers have believed that above age 80 the Gompertz Law did not hold and that mortality rates flattened out. The work done by the Gavrilovs, a husband-and-wife team, reveals that the Gompertz Law holds at least through age 106, and probably higher, but the researchers say mortality data for those older than 106 is unreliable.

The Gavrilovs say the extinct birth cohort of people born between 1875 and 1895, which they built using the Social Security Administration Death Master File (SSA DMF), reveals beyond question that the mortality rate of people in that cohort aligns with the Gompertz Law.

“It amazes me that the Gompertz model fits so well nearly 200 years after he proposed it.  I like the approach of using extinct cohorts methods on SSA DMF data by month and the use of male-female ratios to test the quality of the data at advanced ages,” said Tom Edwalds, Assistant Vice President Mortality Research, for the Munich American Reassurance Company.

Prior estimates of the number of centenarians in the United States were made in less direct ways that were subject to error. They depended, for example, on people self-reporting their age in the U.S. Census, which is less reliable than having actual birth and death data.

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Increasing attention is turning towards the what could become the sustainable alternative to livestock – test tube meat. Speculation that the current food market will be unable to provide for the world’s growing population, projected at 9.3 billion by 2050 by the U.S. Census Bureau, has led to the development of in vitro meat.

Experts in Holland were the first to use cells from a live pig to replicate growth in a petri dish, resulting in the advent of “in vitro” or cultured meat. The break through is hypothesized to reduce billions of tons of greenhouse gases emitted each year by farm animals, solve world hunger and put an end to the ethical impacts of the meat industry.

So far the biggest slab of meat grown is about the size of a contact lens which contains millions of cells. The next step is to try turning these cells into muscle tissues through the use of biodegradable scaffolding platforms which will be the same sort of meat taken from the flesh of an animal.

However, muscles require stimulation or else the atrophy and die. To solve this problem with lab-cultured meat, scientists are currently using electrical impulses to stimulate the muscle cells grown in the lab, but have yet to discover a mass-factory scale solution.

Eventually there should be no differential between the taste of animal meat and test-tube meat, leading from the production of mincemeat to that of steak. While the product may be initially unappealing to many, the statistics make a compelling case for the animal substitute.

This more sustainable method of producing protein promises to increase the changes of food security for the world’s poor while simultaneously protecting the environment. The projected resource savings from artificial meat in an Oxford study estimated that it could be engineered to use only 1 percent of the land and 4 percent of the water required for conventional meat.

According to the scientists from Oxford University and Amsterdam University, that means that lab-grown tissue would reduce greenhouse gases by up to 96 percent in comparison to raising animals. The link between meat consumption and climate change have been widely acknowledged for years, due to the deforestation which often comes along with livestock farming.

In an increasingly crowded world where there are 925 million chronically hungry people, according to the UN’s World Food Program, a more sustainable approach to food is desperately needed. More than one in seven people do not have enough protein and energy in their diet, with 98 percent living in the developing world.

Increased meat-eating has long been associated with a country’s rising affluence, but perhaps man-made meat could change all of that. Hanna Tuomisto, a researcher at Oxford University, believes that aside from the environmental benefits, lab-cultured meat would also provide cheap nutrition.

Tuomisto also predicts that if more resources were put into the research, the first commercially lab-grown meat could be available within the next five years. Due to the interconnected nature of the potential problem solving test tube meat, groups such as the anti-meat organization People for the Ethical Treatment of Animals are already contributing to more research.

To Read 8 Ways In Vitro Meat Will Change Our Lives, visit http://hplusmagazine.com/2009/11/17/eight-ways-vitro-meat-will-change-our-lives/

Sources:

http://www.npr.org/2011/08/30/139786731/tube-burgers-the-world-of-in-vitro-meat

http://www.globalenvision.org/2011/08/03/test-tube-meat-could-it-feed-world-one-day

http://www.npg.org/facts/world_pop_year.htm

http://www.timesonline.co.uk/tol/news/science/article6936352.ece

http://www.guardian.co.uk/environment/2011/jun/20/artificial-meat-emissions

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Despite rocketing fuel prices and rampant obesity, active travel in the U.S. rose only slightly from 2001 to 2009, with an increase in the share of trips by walking and cycling just 1.9 percent and 0.1 percent respectively, according to the National Household Travel Surveys. The study, published on May 6 in the American Journal of Public Health, was written by four PhD researchers (John Pucher, Ralph Buehler, Dafna Merom and Adrian Bauman) interested in monitoring rates of walking and biking among Americans, as this is the healthiest and most sustainable means of transport we actually have.

Unlike the old statistical methods used by the U.S. Census Bureau, which reported a sharp decrease in the number of people walking to work as their main mode of transportation over the last five decades (from 10.3 percent in 1960 to 2.9 percent in 2009), the telephone surveys conducted by NHTS used more sophisticated systems of capturing data, and instead reported on travel in the U.S. for all trip purposes.

Results did not display any satisfactory turnaround in the usual travel behavior of Americans, who in fact are said to be excessively car-addicted and sedentary, compared to worldwide standards. “American cities have a long way to go to catch up to walking and cycling levels in Europe, which are about 3 to 5 times higher than in the United States,” researchers stated.

However, the good news is, such an alarming pattern is slowly reversing. Analysis published on the American Journal of Public Health revealed that “the average American made 17 more walk in 2009 than in 2001, covering 9 more miles per year, compared with only 2 more bike trips, and 5 more miles cycling.” Moreover, in 2009 walk and cycle trips for utilitarian purposes, such as going to work or accessing public transport, were overwhelming, accounting for three quarters.

But why are Americans are so slow to get used to the idea of walking and cycling as everyday modes of transport? Laziness? Suburban sprawl? Nothing of the kind. According to John Pucher, professor at Rutgers University in New Brunswick, N.J., and his research colleagues, it deals with an enormous question of lack of infrastructure, such as protected lanes for cyclists, good sidewalks for pedestrians, crosswalks, intersection crossings and so on.

In fact, traveling by bike or walking is difficult if you feel your environment is threatening and dangerous: “getting from point A to point B is a really daunting experience in many American cities because of such lousy pedestrian and cycling facilities,” Pucher argued.

Surveys detected shocking differences among the various population subgroups concerning active travel trends. Walk and bike trips increased a little only among men, the employed, the 45-64 year olds, those well-educated, and without a car. Conversely walking and biking declined for all the most vulnerable: namely women, children and seniors.

Suffice it to say that in 2009 walking significantly dropped among the elderly by up to 4.2 percent, while cycling prevalence for women revealed to be almost three times lower than men. “That says we’re doing something wrong in the United States,” Pucher pointed out.

The warning issued by NHTS researchers cannot be underestimated, not only for pollution concerns, but also because there is mounting evidence regarding the relationship between sedentary lifestyle and several health diseases.

According to World Health Organization , physical inactivity is, along with tobacco and alcohol, one of the main risk factors for mortality. Also the United States, Australia and United Kingdom continue to register extraordinarily high obesity rates, with an even worsening epidemic among children and adolescents.

The time has come to work for a more sustainable life, yet, as Pucher said, being very clear how to do it, “we just don’t do it.”

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