Education 'protects' poor women from fattening effects of rising wealth, say researchers in a new study. Obesity levels among women in low- and middle-income countries tend to rise in line with wealth as they purchase more energy-dense foods. But a new University College London (UCL) study, "Education Modifies the Association of Wealth with Obesity in Women in Middle-Income but Not Low-Income Countries: An Interaction Study Using Seven National Datasets, 2005-2010," published March 7, 2014 in the journal PLOS ONE suggests that more educated consumers make better food choices that mitigate this effect. The study showed that in middle-income countries, obesity levels among women with secondary or higher education are 14-19% lower than less-educated women of similar wealth.
Here in Sacramento, people buy the food they can afford, and in some neighborhoods supermarkets are scarce. So people rely on seasonal farmers' markets, if they're affordable, or seasonally, make use of urban gardens and food banks to make the food budget stretch across the month.
The new research looked at the relationships between obesity, education and wealth in over 250,000 people across four middle-income and three low-income countries between 2005 and 2010. More educated people are typically wealthier, and this study was the first to isolate the effects of education and wealth to unpick their distinct effects.
Each household's "wealth index" was measured by evaluating their possessions, housing situation and access to basic amenities.
Based on these criteria, they were divided into five wealth brackets on a scale of 1-5, from richest to poorest, in each country. The middle-income countries examined were Egypt, Jordan, Peru and Colombia. In Egypt, where 43% of the 32,272 women surveyed were obese, the effect of wealth on obesity was reduced as education levels increased. The increased risk of obesity associated with a rise in wealth bracket was 39% for women with primary education or below, 25% for women with secondary education and only 2% for women with higher education.
"For the first time, we have studied the interaction between wealth and education and found that they have fundamentally different effects on obesity," says lead author Dr Amina Aitsi-Selmi, Wellcome Trust fellow at UCL, according to the March 7, 2014 news release, Researchers gain new insights into ancient Pacific settlers' diet. "As emerging economies are exposed to a flood of calories from the global food market, rising wealth often leads to rising obesity as people buy energy-dense foods.
Does investing in women's education protect against rising obesity rates?
"Our study suggests that investing in women's education protects against this effect by empowering individuals to look after their health. However, it is not a substitute for good public health systems and the regulation of commercial activity such as the aggressive marketing that puts pressure on individuals to consume unhealthy products and take unnecessary risks with their health."
In the low-income countries of India, Nigeria and Benin, the relationship between education and wealth was more difficult to unpick. In India, where only 2.8% of the 113,063 women surveyed were obese, wealth had a profound impact on the risk of obesity. For each increase in wealth bracket, the risk of obesity increased by 123%.
Jump in obesity risk for low-income areas
"The jump in obesity risk that people in low-income countries experience as they become wealthier is likely related to the environment of scarcity," explains Dr Aitsi-Selmi, according to the news releease. "The weight of scientific evidence that we have leaves no doubt that the environment we live in is largely responsible for the obesity epidemic."
In fields such as nutritional anthropology, scientists look for clues in the diets of ancients around the world. Is there a gender difference between the variety and protein sources men had that weren't given to women in a particular society? In another study by different researchers, the scientists gained new insights into ancient Pacific settlers' diets in one study from New Zealand's University of Otago researching 3,000-year-old skeletons from the oldest known cemetery in the Pacific Islands. The scientist's findings are casting a new light on the diet and lives of the enigmatic Lapita people, the likely ancestors of Polynesians.
Researchers found unequal food distribution, suggesting that males may have been considered of higher status in Lapita society and treated preferentially, the scientists explain
In this new study researchers looked at the diets of the ancient ancestors of the Polynesians and Melanesians. Their results—obtained from analyzing stable isotope ratios of three elements in the bone collagen of 49 adults buried at the Teouma archaeological site on Vanuatu's Efate Island—suggest that its early Lapita settlers ate reef fish, marine turtles, fruit bats, free-range pigs and chickens, rather than primarily relying on growing crops for human food and animal fodder.
The findings, "Lapita Diet in Remote Oceania: New Stable Isotope Evidence from the 3000-Year-Old Teouma Site, Efate Island, Vanuatu" are newly published online March 5, 2014 in the prestigious international journal PLOS ONE. Study lead author Dr Rebecca Kinaston and colleague Associate Professor Hallie Buckley at the Department of Anatomy carried out the research in collaboration with the Vanuatu National Museum and researchers from the University of Marseilles and CNRS (UMR 7269 and UMR 7041) in France and The Australian National University, Canberra.
Dr Kinaston says the study is the most detailed analysis of Lapita diet ever undertaken and provides intriguing insights into the socio-cultural elements of their society. "It was a unique opportunity to assess the lifeways of a colonizing population on a tropical Pacific island," she says, according to the March 5, 2014 news release, "Researchers gain new insights into ancient Pacific settlers' diet." The researchers analyzed the isotopic ratios of carbon, nitrogen and sulfur in adult human bone collagen and compared these with ratios in ancient and modern plants and animals from the location, which provided a comprehensive dietary baseline.
There's a long-running debate about sustainability during colonizations around the world
"Examining these ratios gave us direct evidence of the broad make-up of these adults' diets over the 10-20 years before they died, which helps clear up the long-running debate about how the Lapita settlers sustained themselves during the early phases of colonizing each island during their eastward drive across the Pacific." Dr Kinaston says, according to the news release, that it appears the new colonists, rather than relying mainly on a "transported landscape" of the crop plants and domesticated animals they brought with them, were practicing a mixed subsistence strategy.
"The dietary pattern we found suggests that in addition to eating pigs and chickens, settlers were also foraging for a variety of marine food and consuming wild animals—especially fruit bats—and that whatever horticultural food they produced was not heavily relied on," she says, according to the March 5, 2014 news release, "Researchers gain new insights into ancient Pacific settlers' diet." Isotopic analysis of the ancient pig bones found at the site also suggests that they were free-ranging rather than penned and given fodder from harvested crops.
Researchers found a gender difference in diet compositions: Men had more protein and variety in foods
The study of the human bones revealed a sex difference in diet compositions, showing that Lapita men had more varied diets and greater access to protein from sources such as tortoises, pigs and chicken than women did. "This may have resulted from unequal food distribution, suggesting that males may have been considered of higher status in Lapita society and treated preferentially," Dr Kinaston says in the news release.
Grants that funded the overall research project came from the Australian Research Council, Pacific Biological Foundation, National Geographic Society, Royal Society of New Zealand-administered Marsden Fund and the University of Otago. Other funding came from CNRS: Aix-Marseille Université.