Metabolic dysfunction–associated steatotic liver disease, or MASLD, is emerging as one of the most prevalent liver diseases in the United States. This condition often develops without noticeable symptoms, leaving many unaware until it is detected through blood tests or imaging. As the rates of obesity and type 2 diabetes continue to rise, the prevalence of MASLD has increased, affecting approximately 30% to 40% of adults worldwide.
Understanding MASLD and Its Rising Prevalence
According to Dr. Leana Wen, an emergency physician and adjunct associate professor at George Washington University, MASLD occurs when excess fat accumulates in the liver, typically in individuals with underlying metabolic issues, such as obesity and type 2 diabetes. Unlike alcoholic liver disease, MASLD is not related to alcohol consumption. Previously known as nonalcoholic fatty liver disease (NAFLD), this condition is now recognized as the most common chronic liver disease globally.
The disease is particularly concerning in the United States, where it affects around 1 in 3 adults. The statistics are even more alarming among those with type 2 diabetes, with 60% to 70% of these individuals affected, and among those with obesity, where the figure rises to 70% to 80%. Over time, MASLD can lead to severe complications, including liver inflammation, scarring, cirrhosis, liver failure, and liver cancer. It has also become a leading cause of liver transplants in select populations.
Symptoms, Diagnosis, and Risk Factors
The challenge with MASLD lies in its subtle onset. Most individuals do not experience symptoms in the early stages. Dr. Wen notes that some may feel unusually fatigued or experience vague discomfort in the upper right abdomen, but these signs can easily be overlooked. As the disease progresses, more severe symptoms may arise, including jaundice (yellowing of the skin or eyes), dark urine, swelling, and confusion. By this stage, significant liver damage may have already occurred.
Diagnosis often relies on routine blood tests that reveal abnormal liver enzymes or imaging studies, such as ultrasounds, that indicate a “fatty” liver. Healthcare providers typically consider metabolic risk factors, including excess weight, diabetes, high blood pressure, and high cholesterol, when diagnosing MASLD. In some cases, further imaging or a liver biopsy may be necessary to confirm the diagnosis and assess liver damage.
The condition is most commonly diagnosed in adults with metabolic risk factors, particularly those aged 50 and above. However, MASLD is not exclusive to older adults; approximately 10% of children aged 2 to 19 are also affected, according to the National Institute of Diabetes and Digestive and Kidney Diseases. In the United States, prevalence varies among ethnic groups, with the highest rates observed in Hispanic individuals, followed by non-Hispanic Whites and Asian Americans.
Treatment and Prevention Strategies
Good news exists for those diagnosed with MASLD: the condition can often be improved or even reversed, particularly if caught early. The cornerstone of treatment is weight loss, which can lead to significant reductions in liver fat and inflammation. Regular physical activity, such as brisk walking several times a week, is also beneficial in improving insulin sensitivity and reducing liver fat.
Until recently, there were no specific medications approved for MASLD. However, the U.S. Food and Drug Administration has approved two medications for the more advanced form of the disease known as metabolic dysfunction–associated steatohepatitis (MASH), which includes liver inflammation and scarring. These drugs, Rezdiffra (resmetirom) and Wegovy (semaglutide), are intended to complement lifestyle changes rather than replace them.
To protect liver health, individuals should focus on maintaining a healthy weight, engaging in regular physical activity, and following a balanced diet rich in lean proteins, whole grains, and vegetables while minimizing added sugars and ultra-processed foods. For those with diabetes, high blood pressure, or high cholesterol, it is crucial to work closely with healthcare providers to manage these conditions. Routine blood tests can help identify individuals at risk for MASLD, allowing for timely evaluation and intervention.
In conclusion, as the awareness of MASLD grows, individuals and healthcare providers alike must prioritize liver health. Early detection and lifestyle modifications can significantly impact the course of this common yet often overlooked condition.
