(Reuters Health) - People who have fatty liver disease that wasn’t caused by heavy drinking may still need to avoid alcohol if they want to prevent their liver damage from getting worse, a Korean study suggests.

Most people have a little bit of fat in their liver, but fatty liver disease can be diagnosed when more than 5 percent of the liver by weight is made up of fat. If the condition isn’t linked to liver damage from heavy drinking, it’s known as non-alcoholic fatty liver disease (NAFLD) and is most often associated with obesity and certain eating habits.

For the current study, researchers examined data on 58,927 Korean young and middle aged adults with NAFDL who had low levels of fibrosis, or scarring on the liver. After following half of these patients for at least 8.3 years, 5,630 people had progressed from low to more advanced levels of fibrosis.

Moderate drinkers were 29 percent more likely to have worse fibrosis by the end of the study than people who didn’t drink at all. Men were considered moderate drinkers when they had up to about two drinks a day, while women could have up to about 1.5 drinks daily.

But “light drinkers” who averaged less than 10 grams of alcohol (less than one drink) daily, were also 6 percent more likely to have their fibrosis become more advanced than people who avoided alcohol altogether, the study team reports in Hepatology.

“There was no safe limit of alcohol intake in relation to fibrosis progression,” said senior study author Dr. Seungho Ryu of Kangbuk Samsung Hospital and Sungkyunkwan University School of Medicine in Seoul, South Korea.

While the study wasn’t designed to prove whether or how alcohol might directly cause advanced fibrosis in people with NAFLD, it’s possible that drinking leads to more extensive scarring because it contributes to inflammation and kills cells in the liver, Ryu said by email.

At the start of the study, researchers used ultrasound results to assess the extent of liver damage during physical exams and relied on questionnaires to determine participants’ drinking habits.

To determine if people experienced worsening fibrosis, researchers used non-invasive assessments that focused on things like whether an individual was obese, or had slightly elevated blood sugar, full-blown diabetes or low levels of the liver protein albumin that can indicate worsening liver function.

One limitation of the study is that researchers didn’t use a liver biopsy to diagnose worsening fibrosis, which is invasive but can provide more accurate results than the methods used in the study.

The study also didn’t distinguish between different types of alcohol.

“The question still remains as to whether wine, particularly red wine (versus beer or liquor), may have some heart and diabetes protective effects in small amounts (no more than 1 glass on average per day) in particular in patients with NAFLD who are at high risk for complications and death from heart disease and diabetes,” said Dr. Lisa VanWagner of the Northwestern University Feinberg School of Medicine in Chicago.

Still, people who drink need to keep in mind that the empty calories in alcohol may contribute to worsening liver disease, VanWagner, who wasn’t involved in the study, said by email.

“The main contributor to NAFLD is obesity, and weight control within a healthy range is the most important thing that people can do to lower their risk of liver disease,” VanWagner noted. “If abstinence is not achievable then general health guidelines suggest that no more than one drink per day for women and no more than two drinks per day for men is low-risk drinking.”

SOURCE: bit.ly/2nk4qE6 Hepatology, online July 17, 2018.