Study links higher risk of adult obesity with extra cash from government program
| 20 October 2008
BERKELEY — While a poverty-alleviation program launched by the Mexican government that has been modeled in the United States and around the world has led to improved health and cognition outcomes in children, a new study by University of California, Berkeley, researchers says that the cash component of the program has a downside for adults.
The program, called Oportunidades, provides money to impoverished families on the condition that they participate in health-promoting activities, such as getting annual health checkups and attending nutrition and hygiene education seminars. This is in contrast to traditional welfare programs that provide cash to families based solely upon their income or where they live.
The study published today (Monday, Oct. 20) in the Journal of Nutrition found that adults in households that received more cash from the program were more likely to be overweight, obese and have higher blood pressure than those who had received less money over time.
"It's a controversial finding because it suggests that adults are not necessarily spending the money wisely for themselves," said Lia Fernald, UC Berkeley assistant professor of public health nutrition and lead author of the study. "It's not clear why the cash is having this effect, but it could be because people who suddenly have more cash are able to buy more high-calorie soft drinks, alcohol or snacks that they couldn't afford before, though we did not analyze how the money was spent in our study. This result could also reflect trends in the developing world, particularly in rapidly changing economies, of increased availability of foods high in fat and sugar in place of healthier cereals, fruits and vegetables."
The surprising study results come on the heels of an earlier paper, authored by the same UC Berkeley researchers, which showed that overall, the conditional cash transfer program was linked to better health outcomes among adults.
The researchers noted that the earlier paper compared adults who had been enrolled in Oportunidades for 3.5 to 5 years with newly enrolled adults who had not yet received any program benefits. In the new study, the authors wanted to specifically examine the role played by money accumulated through the program.
The Mexican government randomly selected communities that were eligible to enroll when the program first launched and allowed the remaining communities to enroll 18 months later. Households who enrolled first thus received more money cumulatively than ones enrolled later.
The study linked people's receipt of greater amounts of cash with higher body mass index, higher diastolic blood pressure and a higher prevalence of overweight and moderate to severe obesity in adults. In their analysis, the study authors controlled for other factors that could have influenced the results, such as length of time enrolled in the program, age, gender and education level.
"Our paper is in line with something that other economic studies have found: As people come out of poverty, they spend money on foods that can lead to obesity," said study co-author Paul Gertler, UC Berkeley professor of economics and health services finance. "It is interesting to note that in other work, we find the cash component of the program lowers obesity in young kids. One possible reason for this difference is that adults are using increased cash to provide protein and micronutrients for their children, whereas they are purchasing soda, alcohol and junk foods for themselves."
The researchers noted that the initial and central aim of the Oportunidades program was to improve health and development outcomes for children, a goal that the program has largely achieved. The impact of the program's components on adult health, however, has been a matter of debate.
"It's not unusual for adults to make better health and nutrition decisions for their kids than they do for themselves," added Fernald. "It's also possible that healthier foods and beverages are not available in the rural and impoverished regions where the Oportunidades program operates, and so adults may not have adequate access to sufficient resources for the whole family."
When the researchers factored in the length of time individuals were enrolled in the program, they noticed that those enrolled the longest - 5 years - had slightly better health outcomes than those enrolled for only 3.5 years. While the differences were not consistently significant statistically, the researchers pointed out that the trend, at least, was in the right direction.
Combined with the results from the earlier study showing that adults in the program had lower blood pressure and lower body mass index, the new findings suggest that the program's non-cash interventions - screening for chronic diseases and educational classes - seem to be counteracting the negative effects of extra income, the researchers said.
Launched in 1997, Oportunidades serves more than 5 million Mexican families and has been replicated in more than 20 developing countries. In 2007, New York City established the first conditional cash program in the United States that was modeled after Oportunidades.
"Our data suggest that if cash is given to adults unconditionally, with no health education or promotion component to balance it out, it could cause an increase in obesity and hypertension for adults," said Fernald. "What this study shows is that a strong focus on health education and prevention is a really critical part of any cash transfer or welfare program targeting adults."
The paper was also co-authored by Xiaohui Hou, an economist at the World Bank Group in Washington, D.C., who was a graduate student at UC Berkeley while the study was conducted.
This study was supported by the National Institute of Child Health and Human Development, the Fogarty International Center at the National Institutes of Health, the University of California Institute for Mexico and the United States, and the Oportunidades program.