Obesity and Type 2 diabetes are becoming more common all over the world. But the tiny Samoan islands now have the highest rates. An epidemiologist blames changes in diet brought on by globalization.
Dribs and drabs of research from a few countries around the world have raised concern that diabetes is growing as a cause of death and disability. But the first coordinated global look at the disease, published in The Lancet this week, has fully sounded the alarm.
Pooling data from 751 studies involving 4.4 million adults, researchers estimated that the number of adults with diabetes in 200 countries has nearly quadrupled, from 108 million in 1980 to 422 million in 2014. And the disease is growing faster in low- and middle-income countries than in high-income countries. The lowest prevalence of diabetes — about 5 percent of the population — was in northwestern Europe. At the other end of the spectrum, approximately 1 in 4 adults has diabetes in the Pacific islands of Polynesia and Micronesia. American Samoa holds the dubious distinction of the highest rate of diabetes in the world: 30 percent of the adult population.
NPR talked with Dr. Majid Ezzati of the School of Public Health at the Imperial College of London, who designed the study and oversaw the research. The interview has been edited for clarity.
We hear a lot about the exportation of the worst of the Western diet — fast food, soda — to developing nations. Is that what’s causing the increase in diabetes around the world?
I think that’s an old idea, and overstated. After all, there are features of the diet in the developed world that are good. The role of technology and affluence has been to provide whole grains, fresh fruits and vegetables all year round. It would be great if we could export that. The increase in diabetes is a food story, but not necessarily fast food.
So as regions of the world climb out of poverty, people eat more of whatever they’d been traditionally eating.
Yes, and obesity goes up. I emphasize that it doesn’t have to be a lot of fast food and commercial food. Eating more of the same foods increases BMI [body mass index]. Calories are calories and carbs are carbs. If they’re eating the white rice that they traditionally ate, but eating more of it, that could be increasing BMI.
What else might be causing the increase?
The short answer is that we don’t completely know. But one idea is that people who were malnourished, either as fetuses or as young children, and are now eating more and gaining weight, are more susceptible to diabetes. The evidence is accumulating that poor childhood conditions can affect how we produce or use insulin.
Other than the Pacific Island nations, which areas of the world are the most worrisome?
We’ve seen increasing rates of obesity, and diabetes, in North Africa, the Middle East, Saudi Arabia, and in parts of the Caribbean and Latin America. And Africa is not a uniform place. We’ve seen BMI going up quickly in West Africa.
What can be done to stem the rise in diabetes?
Health systems have a role in catching people who are at high risk for diabetes, people call it pre-diabetes, and motivating them to change their diet or sometimes using low-cost medications. These are programs like the Diabetes Prevention Program in the United States. Iran, for example, has a highly effective program in finding people at high risk of diabetes. Some of the Pacific Islands are trying to do that. And South Africa is starting to use the same infrastructure it uses to manage HIV to manage early stage diabetes.