A small informal study published by New Scientist suggests that liver experts may have overlooked a major contributor to non-alcoholic fatty liver disease: alcohol.
Excessive alcohol is defined by the American Association for the Study of Liver Diseases guidelines as >21 drinks a week for men and >14 drinks a week; this has been associated with fatty liver disease. However, more modest intakes have not been well defined as a health risk to the liver. The accumulation of liver fat, when excessive drinking has been ruled out, has generally been associated with the rising rate of obesity. Fatty liver disease is currently found in approximately 30% of the US population. For those with diabetes the prevalence can be as high as 50-70%. Other conditions, such as hypothyroidism, low testosterone, sleep apnea, and polycystic ovarian syndrome may cause fatty liver disease independent of obesity.
In the study, a group of 14 New Scientist staffers volunteered to participate. They were all social drinkers but denied excessive alcohol use. 10 of them were selected to stop drinking for 5 weeks, and 4 staffers were used as controls. Questionnaires, blood tests, and liver ultrasounds were completed before and after the intervention.
Surprisingly, in just 5 weeks, liver fat decreased on average by 15 per cent, and almost 20 percent in some individuals. Other improvements included improvement in fasting blood sugars, cholesterol, and sleep.
While the study is clearly preliminary, the measure of liver fat via ultrasonography provides objective data that suggest that a short break from alcohol by social drinkers may decrease their liver fat.
Fatty liver disease has been linked to multiple diseases including diabetes, cardiovascular disease and overall greater mortality. Compared to people of the same weight, people with fatty liver are more likely to have hypertension and elevated cholesterol.