People who engage in occasional heavy drinking face a threefold higher risk of liver damage when they already have a liver illness known as MASLD, according to an April 2 peer-reviewed study published in the Clinical Gastroenterology and Hepatology journal.
MASLD, or metabolic dysfunction-associated steatotic liver disease, is a condition in which fat builds up in the liver of people who drink little to no alcohol and face obesity issues, high blood pressure, high cholesterol, or diabetes, according to the American College of Gastroenterology.
This fatty liver condition is estimated to affect up to 30 percent of individuals in the United States and is the most common liver condition in the country.
In the study, researchers analyzed data of 8,006 individuals from the 2017–2023 National Health and Nutrition Examination Survey, out of which 3,969 were found to have MASLD.
Among those with MASLD, 632 individuals, or 15.9 percent, engaged in episodic heavy drinking, which was associated with “significant” and “advanced” liver fibrosis, a condition in which the healthy tissues of the organ get scarred and rendered unable to function properly.
“Episodic heavy drinking is prevalent in MASLD and associated with 3-fold higher odds of advanced liver fibrosis,” the researchers wrote.
The study defined episodic heavy drinking for men as consuming five or more drinks on any single day, at least once per month. For women, the threshold was set at four or more drinks.
Younger adults and men were more likely to report episodic heavy drinking, Keck School of Medicine at the University of Southern California (USC), Los Angeles, whose researchers conducted the study, said in an April 12 statement.
“This study is a huge wake-up call because traditionally, physicians have tended to look at the total amount of alcohol consumed, not how it is consumed, when determining the risk to the liver,” said Brian P. Lee, the principal investigator of the study.
“Our research suggests that the public needs to be much more aware of the danger of occasional heavy drinking and should avoid it even if they drink moderately the rest of the time.”
While MASLD is typically not defined as alcohol-related, the team found that almost 16 percent of people in this group were episodic heavy drinkers.
According to Lee, consuming large quantities of alcohol at once can overwhelm the liver and increase inflammation, thus resulting in the organ getting scarred and damaged.
Over the past two decades, alcohol-related liver disease cases have more than doubled, which Lee said was likely driven by higher drinking due to the COVID-19 pandemic, and more people carrying MASLD risk factors, such as diabetes and obesity.
“Although this study focused on patients with MASLD, these findings may also be pertinent to a broader patient population,” Lee said.
“With more than half of adults reporting some episodic heavy drinking, this issue deserves further attention from both physicians and researchers to help better understand, prevent and treat liver disease.”
According to a 2023 post by the American Liver Foundation, liver fibrosis, in its mild or moderate stages, does not cause any symptoms.
If detected early, the situation can be reversed. If fibrosis is left untreated, it can lead to cirrhosis and liver cancer, the foundation warned. Cirrhosis is a condition in which the liver is permanently damaged. As cirrhosis worsens, the liver starts to fail.
Alcohol consumption is associated with a host of other health consequences in addition to liver fibrosis.
For instance, alcohol has been linked to several types of cancers, including those of the liver, colorectal, oral cavity, and female breasts.
A September 2025 study published in the BMJ Evidence-Based Medicine suggested that drinking any amount of alcohol may increase the risk of developing dementia, which negatively affects memory and thinking ability.
Even consuming a single glass of wine per week can potentially raise dementia risk among people, the study said.
In November 2025, a study published in the journal Neurology said that individuals consuming alcohol three or more times per day faced a higher risk of stroke at a younger age than those who didn’t engage in such drinking.