The global obesity epidemic just keeps getting worse. In 2015, about 1 in 3 of the world’s population — 2.2 billion people — were overweight, according to a major new study published Monday in the New England Journal of Medicine (NEJM).
The study also reports that, globally, more than 1 in 10 adults (603 million) and about 1 in 20 children (107 million) were obese.
In 70 countries — including the United States — the prevalence of obesity is now at least twice what it was in 1980, and it has continuously increased in most other countries.
Furthermore, the rate of increase in childhood obesity is now outpacing the rate in adult obesity in many countries — a somber portent for the future.
These findings are evidence of “a growing and disturbing global public health crisis,” write the authors of the paper — a crisis that is detrimentally affecting the lives of individuals, as well as the health economies of entire countries.
Among the 20 most populous countries, the highest level of obesity among children and young adults was in the United States (almost 13 percent). The highest numbers of obese children, however, were in China (15.3 million) and India (14.4 million).
Egypt had the highest rate of adult obesity (35 percent), while Bangladesh and Vietnam had the lowest (around 1 percent). In terms of numbers of obese adults, the United States topped the list (79.4 million), followed by China (56.3 million).
Obesity not the only concern
As the report points out, a high body mass index (BMI) accounted for 4.0 million deaths globally in 2015, or about 7 percent of all deaths that year. But — and this may surprise many readers — almost 40 percent of those deaths occurred in people who were overweight (BMI of 25 to 29.9) but not obese (BMI of 30 or greater).
Globally, the top cause of death related to a high BMI was heart disease. It’s responsible for about 40 percent of such deaths. Those deaths would be even more frequent, the study notes, if not for improvements in treating heart disease (such as drugs that control high blood pressure) and in lowering its risk (such as policies that have encouraged fewer people to smoke).
Of course, treatments for heart disease are expensive and place a economic burden on individuals, healthcare systems and governments.
Diabetes was the second-leading cause of BMI-related deaths in 2015. Other causes include chronic kidney disease and various cancers, such as cancers of the esophagus, colon, liver, gallbladder, pancreas, breast uterus, ovary, kidney and thyroid.
Excess weight is also a major contributor to disability worldwide. The report estimates that 37 percent of years lost to disability globally are related to high BMI.
“People who shrug off weight gain do so at their own risk — risk of cardiovascular disease, diabetes, cancer, and other life-threatening conditions,” said Dr. Christopher Murray, an author on the study and director of the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, in a released statement. “Those half-serious New Year’s resolutions to lose weight should become year-round commitments to lose weight and prevent future weight gain.”
But, as Murray and his colleagues also suggest, individuals will not be able to ward off excess weight gain alone. Society-wide interventions — particularly ones aimed are reducing the consumption of high-calorie “junk” foods — are also needed.
“The problem [of the increasing rates of obesity] is not simply a function of income or wealth,” they write. “Changes in the food environment and food systems are probably major drivers. Increased availability, accessibility, and affordability of energy-dense foods, along with intense marketing of such foods, could explain excess energy intake and weight gain among different populations.”
Urbanization and other changes in the “built environment” (how we have designed and structured our homes and communities) may have reduced opportunities for physical activity, but that factor has played a lesser role in the obesity epidemic, the researchers add.
“These changes generally preceded the global increase in obesity,” they explain.
FMI: You can download and read the study on the NEJM website. The study was funded by the Bill and Melinda Gates Foundation. The Institute for Health Metrics and Evaluation has an interactive data visualization tool on its website that you can use to examine estimated country-by-country overweight and obesity trends for the years 1980 to 2015.