ANN ARBOR—Well-intended efforts to improve infant and child health in the developing world in the mid-20th century could be linked with increased risk of diabetes, obesity and heart disease for people born during this period when they reach older age, a University of Michigan researcher found.
People born in developing countries in the 1930s through the 1960s lived their early lives when there was rapid improvement in life expectancy—mostly due to public health interventions involving antibiotics or other medical innovations. But for many of them, their standard of living did not improve, said Mary McEniry, a demographer at the U-M Inter-university Consortium of Political and Social Research, part of the U-M Institute for Social Research.
"Having a higher standard of living often means better nutrition and improved ability to fight off infections," she said. "We know that adult lifestyle—diet and exercise—can be very important in terms of health. However, there are now several studies that suggest that poor living conditions in early life can have long-range consequences on one's health at older ages.
"Adult conditions such as diabetes and heart disease, in some instances, can originate in early life. Thus, the set of circumstances of the 1930s-1960s potentially has long-term unintended consequences of producing a large cohort of individuals who are in poorer health and whose life expectancy is negatively affected by what happened in their early life."
The study looked at historical and survey data on nearly 147,000 older adults in 25 countries of various income levels in Africa, Asia, the Caribbean, Europe, and North and South America.
McEniry said her findings provide a relevant message for policymakers interested in public health interventions being implemented today and their consequences in the long term.
"There are many good programs trying to improve the health of people in the developing world," she said. "Medical and public health interventions have improved people's ability to survive very harsh conditions in early life and often quite dramatically, but if there is little improvement in living circumstances, what will their health at older ages be like?"
This question has particular significance for policymakers anticipating the health care needs of older adults in low- and middle-income countries, which are projected to experience large rises in their older adult population along with projected increases in diabetes and heart disease.
"Given these projections, it is important to understand what explains health at older ages in these settings so that proper interventions can be put into place. This includes adult lifestyle, but in the case of the developing world it also includes early life circumstances," McEniry said.
Her study appears in the recent book "Early Life Conditions and Rapid Demographic Changes in the Developing World: Consequences for Older Adult Health." It was funded by the National Institute on Aging, an institute of the National Institutes of Health.
Established in 1949, the University of Michigan Institute for Social Research is the world's largest academic social science survey and research organization, and a world leader in developing and applying social science methodology, and in educating researchers and students from around the world. ISR conducts some of the most widely cited studies in the nation, including the Thomson Reuters/University of Michigan Surveys of Consumers, the American National Election Studies, the Monitoring the Future Study, the Panel Study of Income Dynamics, the Health and Retirement Study, the Columbia County Longitudinal Study and the National Survey of Black Americans. ISR researchers also collaborate with social scientists in more than 60 nations on the World Values Surveys and other projects, and the institute has established formal ties with universities in Poland, China and South Africa. ISR is also home to the Inter-University Consortium for Political and Social Research, the world's largest digital social science data archive. For more information, visit the ISR website at www.isr.umich.edu.