Study finds growing 'weight extremes' in the developing world

January 16, 2013

(Medical Xpress)—Obese and overweight people are gaining weight rapidly in low-and middle-income countries while those who are severely undernourished are not experiencing similar weight gains, according to a University of Toronto and Harvard School of Public Health study.

This growing divide may force governments in the developing world to care for people who fall dramatically short on their while simultaneously treating health problems associated with obesity, including diabetes and heart disease.

"One might think that as a country grows economically, the majority of the underweight population would move into the average BMI range, but our study shows the opposite: people of average are disappearing," says Fahad Razak, the study's lead author and a U of T clinical fellow working at St. Michael's Hospital's internal medicine unit.

"This growing trend of body weight extremes is going to pose a major challenge for health care and policy leaders," says Razak. "They will need to balance their priorities between addressing health issues afflicting the underweight who happen to be poor, and health issues afflicting the obese and overweight – the upper middle-class and rich."

The study uses information collected in Demographic and Health Surveys (DHS), an American-led project that tracks health and in developing countries. Researchers analyzed the (BMI) of 730,000 women living in 37 countries between 1991 and 2008 and found that as the average BMI in a population increases, the numbers of overweight and are increasing at a much faster rate than the decline in the number of underweight women.

BMI is an indicator of body fat calculated by dividing a person's weight in kilograms by their height in meters squared. Obesity is defined as having a BMI of more than 30.0 kg/m2. Compared to people with a healthy weight (a BMI between 18.5 and 24.9 kg/m2), and (who have a BMI between 25.0 and 29.9 kg/m2) have an increased risk of diabetes, heart disease and stroke, and tend to die younger. At the same time, people who are underweight (BMI less than 18.5) also have an increased risk of death, perhaps from complications related to being malnourished.

"The study is novel because for the first time we are showing that increases in BMI are not happening equally across the board; rather increases in average BMI are largely driven by populations that are already overweight or obese, with little to no change among underweight individuals," says S V Subramanian, professor of Population Health and Geography at Harvard School of Public Health, the senior author of the study. "This divergence in the population with fat getting fatter and lean remaining lean is aligned with general patterns of divergence on other domains such as income, and wealth, which of course, are primary drivers of weight status in these countries."

The researchers' future work will test whether these patterns are also observed in more developed countries.

Explore further: Physician's weight may influence obesity diagnosis and care

More information: The study, "Change in the Body Mass Index Distribution for Women: Analysis of Surveys from 37 Low- and Middle-Income Countries," is published in the January 15, 2013, issue of PLOS Medicine.

Related Stories

Physician's weight may influence obesity diagnosis and care

January 26, 2012
A patient's body mass index (BMI) may not be the only factor at play when a physician diagnoses a patient as obese. According to a new study led by researchers at the Johns Hopkins Bloomberg School of Public Health, the diagnosis ...

Above-normal weight alone does not increase the short-term risk of death: study

July 6, 2012
An evaluation of national data by UC Davis researchers has found that extra weight is not necessarily linked with a higher risk of death.

Mother's BMI linked to fatter babies

August 19, 2011
Babies of mothers with a higher pre-pregnancy body mass index (BMI) are fatter and have more fat in their liver, a study published in September's issue of the journal Pediatric Research has found. The researchers from Imperial ...

Recommended for you

Study finds 90 percent of American men overfat

July 24, 2017
Does your waist measure more than half your height?

Are sugary drink interventions changing people's behaviour?

July 19, 2017
An evaluation of efforts designed to reduce how many sugary drinks we consume shows some success in changing younger people's habits but warns they cannot be the only way to cut consumption.

Young adult obesity: A neglected, yet essential focus to reverse the obesity epidemic

July 18, 2017
The overall burden of the U.S. obesity epidemic continues to require new thinking. Prevention of obesity in young adults, while largely ignored as a target for prevention and study, will be critical to reversing the epidemic, ...

Weight gain from early to middle adulthood may increase risk of major chronic diseases

July 18, 2017
Cumulative weight gain over the course of early and middle adulthood may increase health risks later in life, according to a new study led by researchers from Harvard T.H. Chan School of Public Health. They found that, compared ...

Study finds children carry implicit bias towards peers who are overweight

June 23, 2017
Even children as young as 9 years old can carry a prejudice against their peers who are overweight, according to a new study led by Duke Health researchers. They might not even realize they feel this way.

Mother's obesity boosts risk for major birth defects: study

June 15, 2017
Children of obese women are more likely to be afflicted by major birth defects, including malformations of the heart and genitals, according to a study published on Thursday.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.