“Do what your mother told you”

How old will I be? Many people are concerned about this question at the latest when a long-time companion suddenly dies before their time. The development of average life expectancy in this country seems to have only followed one direction for decades: upwards. Recently, however, the trend has lost some of its momentum, as Roland Rau from the University of Rostock says. In addition, the gap between population groups is becoming ever wider.

“Nowadays, hardly anyone dies before the age of 60 or 70,” explains Rau, Professor of Demography and Senior Research Scientist at the Rostock Max Planck Institute for Demographic Research (MPIDR). In industrialized countries such as Germany, France and Japan, the kink now only begins after the age of 70. According to calculations by the Federal Statistical Office for 2022, life expectancy at birth for men in Germany is 78.2 years and for women it is 82.9 years.

No longer life for everyone

According to a paper by Jim Oeppen from Cambridge University and James Vaupel from MPIDR published in the journal “Science” in 2002, the record life expectancy of wealthy countries has been increasing by around 2.5 years per decade for more than a century and a half. This corresponds to around three months per year – or almost six hours per day, as Rau explains. “This means that a child born today lives around six hours longer than a child born the day before.” And that has been true for more than 150 years.

Since 2000, however, the pace has slowed somewhat, says Rau. The probabilities of death for certain years of life are falling less sharply than before. And: Longer life does not exist equally for everyone. According to a study presented in the “European Actuarial Journal” in 2022 by a team led by actuary Steven Haberman from London’s Bayes Business School, the inequality in mortality rates between socioeconomic groups has increased in many countries. The higher mortality in socially weaker groups drags down the overall development.

Low life expectancy in the Ruhr area

Life expectancy is increasing more every year for wealthy people in this country and in other European countries than for poorer people, and the gap is becoming ever wider. According to experts, this also means that poorer people who have paid contributions to pension insurance all their lives and then only see four or five years of retirement are essentially helping to finance the pensions of wealthier people who live longer.

For Germany, Rau and Carl Schmertmann from Florida State University in Tallahassee (USA) analyzed life expectancy by region in 2020. “We were able to show that life expectancy is highest in the south, especially in Munich and the surrounding area.” It is lowest in Saxony-Anhalt and surprisingly low in the Ruhr area too.

Prosperity is crucial for long life

The correlation analyzes between life expectancy and structural indicators presented in the “Deutsches Ärzteblatt” showed that the unemployment factor had the strongest effect. “Even if this does not explain all the differences, one can still say: the higher the unemployment, the lower the life expectancy in a district.”

It may surprise some people that wealth is so crucial for a comparatively long life. Rau even puts a falling gross domestic product at the top of the list of factors that potentially cost life expectancy, alongside smoking and unhealthy diet and ahead of aspects such as a lack of exercise, a growing number of antibiotic resistances, more people with dementia and environmental pollution.

Life expectancy depends on lifestyle

What role environmental toxins and the intake of toxic chemical substances play and will play in life expectancy is generally difficult to answer, says Rau. At the moment the influence is probably relatively small compared to other factors. At least that is what can be concluded from older studies on heavily polluted regions in the former GDR, in which, contrary to what might be expected, life expectancy was not lower than in other parts of the state.

Data from the GDR as well as countries with a similar rule at the time, such as Poland, Hungary and the Czech Republic, also show that life expectancy there increased after the Iron Curtain fell – noticeably sharply and quickly, as Rau says. Experts see this as an indication that life expectancy also depends on whether you live in a democracy or a dictatorial regime.

Small people live longer than tall people

One of the factors that is often overestimated is genetic makeup. “My family has good genes,” is what people like to say when someone talks about their 90-year-old grandmother and similarly aged relatives. Jim Vaupel, the founding director of Rostock’s Max Planck Institute for Demographic Research, estimated that about a quarter of the variation in life expectancy is due to genetic factors. Other experts assume significantly lower values, as Rau says.

Body size alone is a hereditary factor: in humans, as in other mammals, the smallest specimens live longer than the larger ones. The Sardinians are among the smallest and longest-lived populations in Europe, while the Japanese include the people of Okinawa Prefecture. The 122-year-old Frenchwoman Jeanne Calment was only 150 centimeters tall. According to experts, it wasn’t exactly possible to form a basketball team with other particularly old people around the world.

Child mortality used to be higher

Many people may not be aware of how immensely life expectancy has increased since the beginning of the 19th century. In industrialized countries it is more than twice as high as it was in the thousands of years before the 19th century. Most of the people there only lived to be 25 to 35 years old, and probably even less on average, says Rau. According to analysis of English church registers, life expectancy hardly ever exceeded 40 years until the end of the 18th century.

Above all, it was more hygiene and medical advances that suddenly and sustainably increased life expectancy after all these millennia. In the past, there were always individuals who lived to a ripe old age. Above all, child mortality was immense. Vaccinations against polio, smallpox and measles, for example, have certainly made a significant contribution to increasing life expectancy, says Rau. But there are no concrete values ​​for this.

Medicine ensures longer life

The falling number of fatal infections in childhood and adolescence meant that later years of life became the statistically decisive ones: Since the 1970s, the declining death rate of those over 65 has made the largest contribution to years of life gained, as Rau explains. This in turn is largely due to a reduction in mortality from cardiovascular diseases.

“Just think of the methods of treating cardiovascular diseases that are standard today that would have been science fiction just a few decades ago,” says Rau. Examples include stents, pacemakers, bypass operations or preventive agents such as beta blockers. “The big steps in the development of life expectancy will probably continue to be initiated by medicine.”

Longer life expectancy by curing diseases?

One thing is clear: the so often mentioned “natural death” basically does not exist; there are almost always medically comprehensible underlying diseases and causes of death such as tumors or failing organs. What would happen if cancer were suddenly curable, if dementia or strokes could be completely prevented – would there be a huge jump in life expectancy?

In fact, you can calculate what would happen if you could eliminate a factor overnight, explains Rau. The result is surprising: even with idealized assumptions, the statistical gain in years of life would be relatively small. “It would be maybe three to four years for cancer, five or a little more for cardiovascular disease.”

Life expectancy in the USA is falling

Conversely, economic problems, pandemics or wars can significantly reduce average life expectancy. The USA is currently one of the countries in the Western world with declining life expectancy. “Life expectancy there was already stagnating in the early 2010s, before it fell more sharply with Corona than in other countries.” The main reasons for this are the obesity epidemic and widespread opioid abuse.

It is possible, but by no means certain, that a large proportion of those currently born in this country will live to be at least 100 years old. The life expectancy at birth predicted by the Federal Statistical Office indicates the so-called period life expectancy. “You essentially freeze time and say: What would life expectancy be if mortality did not change in the next 100 or 120 years,” explains Rau.

Pay attention at school

At least in the past, this resulted in a constant underestimation: Looking back, it became clear that the actual average was usually higher than was once predicted when the respective age group was born.

Everyone would like it to continue to be this way in the future. And everyone can increase their own likelihood of a long life – starting with paying attention in school and striving to get a good educational qualification. A study presented in the journal “JAMA Network Open” recently confirmed that higher education is linked to slower aging and higher life expectancy.

The right size is crucial

In general, according to Rau, there is a pretty simple guideline: “Do what your mother told you: don’t smoke; if you drink, drink moderately; “Exercise and eat healthily.” With a healthy lifestyle, middle-aged men and women can live more than 20 years longer on average than with a very harmful one, according to data from a long-term study of former US military personnel.

The right amount is crucial, says Rau. Trying to deprive yourself of a lot of quality of life through excessive self-optimization also makes no sense. The life expectancy expert sees a very specific factor as crucial: “I believe that nutrition has the most potential for creating the best conditions for a healthy and long life on an individual level.”

RND/dpa