Scientific American November 2011
The Latest in Science News
Science of Health: The Ethnic Health Advantage (p 30)
Two populations in the US tend to outlive their often richer neighbours, and Laura Blue explains why in this month's Scientific American Science of Health column. Her work points to one lifestyle factor: smoking.
All other things being equal, people with greater income or formal education in the U.S. tend to live longer and enjoy better health than their counterparts who make less money or have not attended school for as long. Health researchers have long been puzzled by two notable exceptions to these trends. Immigrants from most nations apparently live longer than their native born neighbors in the U.S. In addition, people of Hispanic descent in the U.S. seem to live longer than non-Hispanic whites, who are, on average, richer and better educated.
Blue set out to test whether something as obvious as smoking could explain the immigrants' and Hispanics' life expectancy advantage in the U.S. She and her research partner used death from lung cancer as their metric of a smoking related death since over 80% of deaths from the disease are caused by smoking. The team do not measure smoking habits here, but previous work has suggested non-foreign-born Hispanics smoke substantially less than their US-born counterparts. Their results suggest that in the year 2000 smoking explained more than 75% of the difference in life expectancy at age 50 between Hispanic and non-Hispanic white men and around 75% in women.
Health information is improving in the U.S. and smoking rates are decreasing, but the opposite effect is true in the developing world. "I expect that both the immigrant advantage and the Hispanic paradox may disappear within the next few decades," concludes the author.
Science Agenda: Ban Chimp Testing (p 12)
It is time to phase out invasive biomedical experimentation on chimpanzees, argue the editors of Scientific American in this month's Science Agenda column. Though testing on chimps has provided us with incredible boon of knowledge-contributing to the discovery of vaccines for polio and hepatitis B-now there are alternatives.
Evolutionarily, chimps are our closest living relatives and similar to humans, they show a capacity for fear, anxiety, grief, and depression. The ethical and moral issues that arise from utilizing chimps in experiments are acute. Yet, the NIH seems to be moving in the wrong direction when it recently announced that 180 chimps that were in a biomedical retirement facility would soon rejoin the roughly 800 other chimps that are part of human disease, therapy, and vaccine studies.
The editors recognize that the tradeoffs are difficult to weight and that some may still see a need for invasive testing on chimps to develop crucial therapies. However, they write: "If the U.S. elects to continue testing on chimps, then it needs to adopt stricter guidelines." The U.S. Department of Agriculture, which presently enforces the Animal Welfare Act, needs to establish a committee of scientists, bioethicists, and representatives from animal welfare groups specifically aimed at the ethics of biomedical research on chimps. It is imperative that in the pursuit of solving human diseases, we minimize the harm we cause.