Philip J. Goscienski, M.D.
Will eating seaweed and sushi help you to live longer? You might think so after reading that the Japanese — again — are among those with the longest life expectancy on the planet. According to statistics, a Japanese infant born in 2007 should expect to live 83 years. The life expectancy for a newborn girl in the United States in 2007 was 80.4; her twin brother should expect to be around only for 75.3 years. That brings the average for those American kids to be 77.9.
Life expectancy is a statistical determination that is useful to population experts but not to individuals. Anthropologists have calculated that the life expectancy of a Stone Ager was about 28 years, giving the impression that he or she would be elderly at 30! Yet fossil studies reveal that about 10 percent of humans who lived before the Agricultural Revolution made it past the age of 60. If it were not for homicide, many more would have lived that long.
Infant mortality is one of the main determinants of life expectancy and it helps to explain why it was only about 45 years for Americans in 1900. Once we developed decent plumbing, childhood vaccines and high-quality premature infant care our life expectancy nearly doubled in a century.
Life expectancy is higher in Macau and Andorra than it is in Japan. They are prosperous and have homogenous populations with an infant mortality so low that they would rank among the top 10 nations in the world. High literacy, little poverty and excellent medical care make average life expectancy inevitably high.
If some countries seem to come out ahead of the United States it may be that they calculate infant mortality differently. In Canada, Germany and Austria, the tiniest premature infants are not included in live births. Some countries don't report any infant that dies within 7 days, some not for 30.
Deaths among young persons skew the figures downward. The United States leads many countries in motor vehicle accidents and homicide. Our rates of obesity and type 2 diabetes are deplorable and getting worse. U.S. life expectancy is going to head back down before long.
If those twins born in 2007 have the good sense to avoid tobacco and junk food, to exercise throughout life and stay out of rough neighborhoods they'll probably make it to 100, just like many of their counterparts in Japan, or even Macau.
Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at firstname.lastname@example.org.