# The global landscape of lean metabolic dysfunction-associated steatotic liver disease: insight from Asia and the West

## TL;DR

Lean MASLD is a growing global health issue, especially in Asia, affecting people with normal BMI and linked to genetic and lifestyle factors.

## Contribution

Highlights the distinct clinical and genetic features of lean MASLD, emphasizing its higher prevalence and risks in Asia.

## Key findings

- Lean MASLD affects 5.1% of the global population and is more common in Asia.
- Genetic factors like PNPLA3 and TM6SF2 polymorphisms contribute to lean MASLD in Asia.
- Lean MASLD is associated with higher mortality and non-liver complications.

## Abstract

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as a leading global cause of chronic liver disease, affecting 25–30% of the population. While MASLD is traditionally associated with obesity, lean MASLD—a subset characterized by hepatic steatosis and metabolic dysfunction in individuals with a normal body mass index (BMI)—is increasingly recognized as a distinct clinical entity. Lean MASLD accounts for approximately 5.1% of the global population and is more prevalent in Asia, where genetic predispositions such as PNPLA3 and TM6SF2 polymorphisms, visceral obesity, and high-carbohydrate dietary patterns are key risk factors. Lean MASLD is also associated with significant liver and non-liver complications, as well as increased all-cause mortality risk. Therefore, lean MASLD may pose a significant challenge for practitioners.