More than half a billion people live with diabetes worldwide. The disease affects men, women and children of all ages in every country.

A study published Thursday in The Lancet projects that the number of people with diabetes will rise to 1.3 billion in the next 30 years in every country and territory in the world.

"The new study presents a sobering fact that global figures for Type 2 diabetes will increase. These new figures surpass many of the predictions we had before," Stephen Lawrence, a diabetes primary care expert at the University of Warwick in the UK, told DW.

Diabetes a global health concern

The study used information from the 2021 Global Burden of Disease study, in which researchers examined the prevalence, morbidity and mortality of diabetes in 204 countries and territories from 1990 to 2021 and forecast the prevalence of diabetes to 2050.

"They've used very accurate modeling studies, so it isn't just someone putting their finger in the wind and making a guess," Lawrence said.

Overall, they found that 529 million people around the world were living with diabetes in 2021, with a global prevalence of 6.1%.

By 2050, the study projects, 43.6% of 204 countries will have diabetes prevalence greater than 10%, and more than 1.3 billion people will be diagnosed with Type 1 or 2 diabetes.

Diabetes rates were highest in North Africa and the Middle East, where 8.7% to 9.9% of people have diabetes, but that number is projected to jump to 16.8% by 2050.

The rate in Latin America and the Caribbean is projected to increase to 11.3%.

Qatar had the highest age-specific prevalence of diabetes, with 76% of people aged 75-79 living with the disease in 2021.

Type 2 diabetes behind the rise

The study found that Type 2 diabetes is much more prevalent than Type 1, accounting for 96% of total diabetes cases.

Type 1 diabetes is an autoimmune problem, in which the immune system attacks beta cells in the pancreas, reducing insulin production. Insulin is a vital hormone for regulating blood sugar levels, allowing sugar (glucose) to enter cells. No insulin means the cells can't take up the glucose needed to produce energy.

"Type 1 diabetes is in a very difficult situation, because, without insulin, over a period of weeks they will potentially die," Lawrence said.

Type 2 diabetes is different: It can develop over time through factors such as diet, body mass and age. In 2021, 52% of Type 2 diabetes cases were linked to high body mass index (BMI).

What is causing diabetes rates to rise?

There are multiple causes for the global rise in Type 2 diabetes rates, but changes in the food industry and lifestyles are the major factors.

Lawrence said consumption of hypercaloric foods, increasingly so in lower-income countries, was the elephant in the room.

"Our genes just sadly aren't made to cope with that. It takes a combined effort of the individual and the environment to develop Type 2 diabetes. It takes a good 10 years of sedentary living and the excess consumption of refined carbohydrates," he said.

It's also the increased consumption of cheap ultraprocessed foods that has caused the increased prevalence in lower-income countries.

"In low- and middle-income countries, as countries move away from traditional food and activity cultures toward more industrialization and more fast foods or ready meals, then the combination leads to more diabetes," said Naveed Sattar, a metabolic health expert at the University of Glasgow in the UK.

People living longer with diabetes

Lawrence said another major reason for the rise in numbers was a success story of science.

"Over the years, we've become more adept at diagnosing diabetes, and credit has to be given to primary care throughout the world. Patients have also become more aware, and testing options are far better than they were a decade ago," Lawrence said.

Sattar also pointed out that the biggest driver of the rise in diabetes is actually better survival in people with diabetes due to lower death rates, especially in higher- and middle-income countries.

"The prevalence of diabetes in the UK has risen from 1 in 100 to 1 in 12 people over the last 35 years. Part of this is because people are living longer. Diabetes becomes more common as you age, and we're better at treating diabetes so people aren't dying prematurely of it," Sattar told DW.

He also pointed to differences between ethnic groups in diabetes rates.

"In lower- and higher-income countries, every ethnic group outside whites has higher risks of diabetes. South Asians, for example, carry higher percentage of body fat in tissues like the liver compared with white European people," Sattar said.

Sattar's research suggests there isn't a clear genetic contribution and that the increase could instead be attributed to nutrition.

"When South Asians move abroad, they get taller and leaner, especially in their children. This suggests to me it's not genetic, but more to do with epigenetics and nutrition," he said.

Societal changes needed to reduce diabetes rates

Diabetes is a huge burden on health care systems around the world. The United States spent $327 billion (€301 billion) caring for people with diabetes in 2017, and that's to say nothing about the unquantifiable personal burden of living with diabetes.

What can the world do to avoid a climb in diabetes rates — or even to reduce rates? It's a tough question with no single answer.

Sattar said it came down to food culture. Changing this is a societal issue, not just a medical issue.

"It's a consequence of raising people from poverty and giving them better life qualities. Type 2 diabetes was more common in wealthy people 50 years ago. Now it's more common in poor people, so it's linked to deprivation and poor food quality. Part of that is moving away from cheaper and high processed foods," he said.

Lawrence is optimistic that societies can achieve this, most likely through smaller changes that need to be properly designed, focusing primarily on the people most at risk.

"Look at the tobacco industry," he said. "Forty years ago people said: How can we reduce smoking when it contributes so much to the tax economy? But we've done it. Governments can make decisions about the food industry just as they did around laws for smoking and seat belts."

Edited by: Helen Whittle