For most Tufts students, nutrition isn't much of a concern. They either worry about the freshman 15 or the cost and usefulness of their meal plans - too many meals? Not enough points?
In developing countries, though, nutrition is an issue of survival. Simin Nikbin Meydani is a professor at the Friedman School of Nutrition Science and Policy. She is also the director of the Nutritional Immunology Laboratory at Tufts' Jean Mayer Human Nutrition Research Center on Aging (HNRCA).
In a recent paper, Meydani and her co-authors, Ahou Meydani and Tanvir Ahmed, examined the possibility of using improved nutrition as a disease prevention method within elderly populations of developing countries.
Meydani's research builds upon the successful use of nutrition to prevent disease in children. "Because nutritional intervention strategies have been shown to be cost-effective among children...the potential that a similar strategy could be used to decrease the burden of disease among the rapidly growing population of elderly is intriguing," Meydani's paper said.
The scientific community has received Meydani's work with an element of surprise. "Some have been surprised to see that there is this growing number of elderly in developing countries," she said. "Normally, we don't think of people in developing countries living into old age. Traditionally the focus has been on children and pregnant women and their problems, but the fact is that now we do have this growing population of older people in developing countries, and there are a lot of health-related issues to address."
According to a World Health Organization report by the Commission on Macroeconomics and Health (CMH), only a few different diseases - HIV/AIDS, malaria, tuberculosis, tobacco-related illnesses, and childhood diseases like pneumonia, diarrhea and measles - account for the majority of the world's illnesses. And most of these diseases - often either treatable or preventable through immunization - are exacerbated by poor nutrition.
While these diseases mostly affect people under the age of 60, those members of the population who are ill and live past 60 are still able to transmit disease to younger people. As in the US, the rising proportion of people over 60 is a worldwide phenomenon: A Friedman School of Nutrition report about Meydani's work said that the world population over 60 is expected to triple in the next 45 years.
For developing countries, though, giving attention to the elderly is not as simple as it may seem. "They're already burdened by what they need to do with their children and pregnant women, and now there are the older people with higher instances of chronic diseases and increased vulnerability to infectious disease," Meydani said.
Meydani and her co-authors wrote in their paper that while nutrition does help reduce the amount of infectious disease, its effect on different parts of the population is still hard to estimate: "Infectious diseases can often be treated and cured, which would markedly reduce overall disease burden," they wrote. "It is difficult, however, to assess infectious disease prevalence in the elderly of the developing world because age-specific populations is an arena generally not surveyed. Also, there may be marked variability from region to region."
In addition, the actual connection between nutritional deficiencies and disease can be difficult to assess. "The problem is that there's not enough info about what the nutritional problems are in different regions and how these contribute to disease," Meydani said.
According to a paper released in December 2005 by David Cutler, Angus Deaton, and Adriana Lleras-Muney from the Department of Economics at Harvard University, nutrition has historically been a significant factor in lowering mortality rates.
Cutler, Deaton and Lleras-Muney wrote that during the eighteenth and early nineteenth centuries in England, improvements in agricultural practice combined with higher caloric intake led to longer life expectancy and increased height.
The same paper said that children tend to benefit most from improved nutrition, while older members of the population see fewer effects. Cutler, Deaton and Lleras-Muney wrote that between 1841 and 1950 in England, there was a 30-year increase in life expectancy at birth, but for 10-year-old children, the increase was half as large. Thus, the nutritional benefits seemed to come from better nutrition in early childhood.
Today, the life expectancy of people in industrialized nations is 30 years longer than the life expectancy of people in developing nations, according to the Cutler, Deaton and Lleras-Muney paper.
"While elderly persons in industrialized nations have been striving toward, and largely attaining a state of successful aging, the newly emerging population of elderly persons in less-developed countries are quite far from this goal," Meydani wrote in her paper.
Another interesting finding for Meydani and her team were the deficiencies in elderly people right here in Boston. "One of our surprising findings from our study was that there were some similarities with studies done at nursing homes in and around the Boston area," she said.
"We found that there was actually the same proportion of people who were zinc deficient in the United States and in Ecuador - about 50 percent in each group."
This particular mineral deficiency is an important one. "I was very surprised to find that older people in the United States were zinc deficient - zinc is very important for immune function, so it's very interesting," Meydani said.
Weight was another common health problem for both populations. "We also find that there was about the same percentage in both countries that would be considered overweight," Meydani said.
In order to find solutions and aid the elderly, Meydani pointed towards further research. "We need to conduct research in clinical trials to find the nutrients they need, then look at the health outcome and find if there is in fact improvement in the health outcome," she said.
"It would provide good information for policy makers to determine and decide if it is useful to take steps to improve nutrition."
But even if policy makers have identified the changes that need to be made, it may not be possible to implement those changes. "Even if they have the will, they might not be able to do something about it themselves," Meydani said of governments in developing countries.
"If there is enough awareness worldwide then we might be able to do something about it, but whether the developing countries themselves can do it themselves will depend on their resources - which are already very limited."
Meydani suggested that global awareness will be an important step in addressing this issue. "The important thing is the realization that there is this increase of older people in developing countries," she said. "In fact, they are growing at a much faster rate than in developed countries."
"In 25 years or so, we'll have more elderly people living in developing countries than in developed countries," she added. "We'll have to think about the nutritional deficiencies on a much bigger scale."
