A common but often silent liver condition linked to modern lifestyles is expected to affect nearly 1.8 billion people worldwide by 2050, according to new research.
Metabolic dysfunction-associated steatotic liver disease (MASLD) – previously known as non-alcoholic fatty liver disease – is already one of the most widespread liver conditions globally. An estimated 1.3 billion people were living with it in 2023, representing about one in six people.
The findings, published in The Lancet Gastroenterology & Hepatology as part of the Global Burden of Diseases (GBD) study, suggest the number of cases has risen sharply over the past three decades, increasing from around 500 million in 1990.
Researchers expect that figure to continue climbing, driven largely by population growth as well as lifestyle-related factors such as rising obesity and high blood sugar levels.
Indeed, the study – led by the Institute for Health Metrics and Evaluation at the University of Washington – identifies high blood sugar as the leading contributor to MASLD-related health problems worldwide. This is followed by high body mass index and smoking.
While the condition is more commonly diagnosed in older adults, the largest number of cases is now seen in middle age, particularly among men in their late 30s and women in their late 50s. Overall, men were found to be more affected than women.
Regional patterns also vary. According to The Guardian, prevalence rates have risen significantly in many parts of the world, including a 33% increase in the United Kingdom since 1990, as well as notable rises in Australia and the United States.
Despite the growing number of cases, the study offers a more nuanced picture of its impact. Measures of overall health burden – including years of life lost due to illness or early death – have remained relatively stable.
This suggests that advances in detection, treatment and long-term care are helping people manage the condition more effectively, with many cases identified at earlier stages.
Even so, the rising number of people affected means more individuals could go on to develop complications such as liver cirrhosis or cancer if the condition progresses.
MASLD is often associated with being overweight and typically develops without obvious symptoms. Many people only discover they have it during routine tests for unrelated health issues.
When symptoms do appear, they can include fatigue, general discomfort or pain in the upper right side of the abdomen.
The study also points to disparities between countries. Nations with more limited access to healthcare may be less well equipped to manage the growing burden of the disease.
With a global prevalence of just over 16%, researchers say MASLD is likely to have significant health and economic implications in the years ahead.
Rather than signalling an immediate crisis, the findings highlight the importance of early awareness and prevention – particularly through managing weight, blood sugar and overall lifestyle – as well as strengthening healthcare systems to cope with rising demand.
