Ezzati said the trends are related. “The issue really comes down to people either not having enough to eat or not having enough healthy food to eat,” he said. “It becomes a manifestation of the same problem.”

No government has found a way to stop rising obesity, though some are trying. Mexico, with almost two-thirds of its population overweight or obese, enacted a national tax on sugary beverages in 2014, the first large country to do so. An early evaluation suggests the peso-per-liter levy steered soda sales lower. Ezzati said the world also needs to focus on making more healthy foods competitive with cheap, processed foods. “To me, how to change the price of good things is perhaps the bigger question going forward,” he said.

The Lancet analysis also estimates an alarming rise of extreme cases of obesity. The global rate of severe obesity, or BMI over 35, is on pace to surpass 9 percent in women and 6 percent in men by 2025. That category now includes 39 million adults in the U.S. In 1975, it was 4 million.