Many folks think it’s OK to belt back a few extra rounds on Saturday night if they stay mostly sober during the week.

But saving up your drinks for a single sitting could be a recipe for liver problems, new research suggests.

A team at the University of Southern California’s Keck School of Medicine linked occasional heavy drinking to triple the risk of advanced liver fibrosis — a dangerous type of scarring that can lead to liver failure. 

Their findings — published April 2 in Clinical Gastroenterology and Hepatology — indicate that the way you drink may be just as important as how much.

Occasional binge drinking could be changing liver tissue in profound ways.

“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,” lead author Dr. Brian Lee, a hepatologist at Keck Medicine, said in a news release.

His team focused on episodic heavy drinking, which is defined as four or more drinks in one day for women and five or more for men. 

Researchers looked at data from more than 8,000 U.S. adults and found that even if someone stayed within moderate weekly limits — 14 drinks for men and seven for women — hitting those daily peaks just once a month drastically increased health risks.

More than half of the adults in the study reported episodic heavy drinking.

This is especially concerning for the 1 in 3 Americans who have metabolic dysfunction–associated steatotic liver disease (MASLD). This condition, often linked to obesity and Type 2 diabetes, makes the liver much more vulnerable to the inflammatory shocks caused by heavy drinking.

Among the 8,006 adults who participated in federal health and nutrition studies between 2017 and 2013, nearly 4,000 had MASLD.

Of those, 16% reported episodic heavy drinking. That increased their odds of significant liver fibrosis by 69%, and nearly tripled the odds of advanced fibrosis.

Why?

When a person quickly drinks a large amount of alcohol, the liver becomes overwhelmed. Inflammation spikes, which eventually causes scarring.

The more drinks consumed in one sitting, the greater the scarring seen in participants, the study found.

Researchers noted that alcohol-related liver disease has doubled over the last 20 years, fueled by both changing drinking habits and rising rates of obesity.

“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,” Lee added.

Researchers suggested that patients with MASLD and episodic heavy drinking should be reclassified into another disease category, called metabolic and alcohol-associated liver disease (MetALD).