Experts estimate that 2.1 billion people across the globe are now overweight or obese. This is nearly 30 percent of the world population, and the dramatic rise has mainly occurred only within the last three decades. These are the findings of a new study published this week in the journal The Lancet.

An international consortium of health experts led by the Institute of Health Metrics and Evaluation (IHME) at the University of Washington in Seattle drafted the first-of-its-kind report from surveys involving some 188 nations providing data from 1980 through 2013. The data are summarized and made available to the public online.

The gold standard for defining overweight and obesity remains the Body Mass Index (BMI), a ratio of weight to height that serves as a surrogate estimate of body fat in adult men and women. Normal weight for any given height translates to a range of 18.5 to 24.9 in the BMI scale. A BMI of 25 to 29 is considered overweight. Anything hitting 30 and above indicates obesity.

Overweight and obesity rates have increased during the study period worldwide from 29 percent to 37 percent for men and from 30 percent to 38 percent for women. Men had higher rates of overweight and obesity in developed countries, whereas women had higher rates of overweight and obesity in developing countries.

“Obesity is an issue affecting people of all ages and incomes, everywhere,” said Dr. Christopher Murray, director of IHME and a co-founder of the Global Burden of Disease (GBD) study. “In the last three decades, not one country has achieved success in reducing obesity rates, and we expect obesity to rise steadily as incomes rise in low- and middle-income countries in particular, unless urgent steps are taken to address this public health crisis.”

The prevalence of overweight and obesity in children and adolescents has soared to nearly one quarter of girls and boys in developed countries suffering from being overweight or obese. In developing countries overweight and obese children are at approximately 13 percent, a proportion that also increased over the study period.

Over half of the world’s 671 million obese live in 10 countries (ranked from high to low): U.S., China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan, and Indonesia.

The rise in overweight and obesity presents the health care systems with tremendous future burdens. Risks increase for cardiovascular disease, cancer, diabetes, osteoarthritis, and chronic kidney disease, conditions that are estimated to have killed approximately 3.4 million deaths in 2010 alone.