Occasional Heavy Drinking Poses Major Risk To Liver — Study

 

Many people assume that drinking lightly during the week or month offsets the impact of occasional heavy drinking. However, new research suggests otherwise.

In a study published in Clinical Gastroenterology and Hepatology, researchers found that people with metabolic dysfunction-associated steatotic liver disease (MASLD)—the most common liver condition, affecting about one in three adults—face a significantly higher risk of liver fibrosis, or harmful scarring of the liver, if they engage in episodic heavy drinking.

Episodic heavy drinking is defined as consuming four or more drinks in a single day

for women and five or more for men, at least once a month.

The study found that individuals who consume large amounts of alcohol in one day at least once per month are three times more likely to develop advanced liver fibrosis than those who spread the same total alcohol intake over time.

Younger adults and men were more likely to report episodic heavy drinking. The findings also showed that the more alcohol consumed in a single session, the greater the risk of liver fibrosis.

These results highlight a critical shift in understanding alcohol-related liver risk. Traditionally, physicians have focused on the total amount of alcohol consumed, rather than drinking patterns.

The researchers emphasized that the public needs to be more aware of the dangers of occasional heavy drinking and should avoid it—even if they drink moderately the rest of the time.

In the study, Brian P. Lee, a hepatologist and liver transplant specialist with Keck Medicine of USC, and his colleagues analysed data from the National Health and Nutrition Examination Survey, a long-running, nationally representative study of the United States population.

The analysis included data from more than 8,000 adults collected between 2017 and 2023. The researchers specifically examined the relationship between episodic heavy drinking and advanced liver fibrosis to better understand how drinking patterns—not just total alcohol intake—can cause harm, even among moderate drinkers. Moderate drinking is typically defined as up to seven drinks per week for women and 14 or fewer for men.

The research team focused on MASLD because it commonly affects people with excess weight, obesity, or metabolic conditions such as type 2 diabetes, high blood pressure, and high cholesterol, and its prevalence is increasing.

Although MASLD is not classified as an alcohol-related condition, the researchers wanted to determine whether alcohol still plays a role in its progression.

More than half of the adults in the study reported episodic heavy drinking, and nearly 16% of individuals with MASLD fell into this category.

Lee explained that episodic heavy drinking can harm the liver both directly and indirectly. Consuming large amounts of alcohol at once can overwhelm the liver, increase inflammation, and lead to scarring and long-term damage.

People with MASLD may be especially vulnerable, as conditions such as obesity and high blood pressure can more than double the risk of liver disease.

“With more than half of adults reporting some episodic heavy drinking, this issue deserves further attention from both physicians and researchers to better understand, prevent, and treat liver disease,” Lee said.