Obesity and insulin resistance are a greater risk for fatty liver than previously thought

Being overweight and resistant to insulin constitute a greater risk for fatty liver than was previously thought, according to a study from Linköping University in Sweden that is now being published in the journal Annals of Medicine.

It has long been known that large amounts of alcohol can cause fatty liver. More recent research has shown that obesity and insulin resistance can also cause fatty liver, which in turn is closely associated with diabetes, high blood pressure, and cardiovascular disease.

Thus far it has been seen as sufficient to drink just over half a glass of wine per day for women and one glass for men to bring about fatty liver. Many people with fatty liver have therefore been asked by their physician to abstain from alcohol. If the liver condition nevertheless did not improve, physicians have assumed that the patient ignored their advice and drank too much alcohol anyway.

The two researchers professor Fredrik Nyström and assistant professor Stergios Kechagias at Linköping University are now showing that moderate amounts of alcohol everyday do not cause fatty liver. In their study, 44 individuals participated and were randomized to either abstain entirely from alcohol or drink one glass of red wine per day for women and two glasses for men for three months. Before and after the trial the subjects provided blood samples, and the fatty content of the liver was measured with state of the art magnetic resonance imaging.

"It turned out that the amount of fat in the liver was linked with obesity and insulin resistance and was almost not at all affected by the red wine. Specifically, after three months, none of the the wine drinkers had developed fatty liver or elevated liver transaminases" explains Stergios Kechagias, who is a liver specialist at LiU.

What's more, the harmful LDL cholesterol was 16 percent lower at the end of the study in those who drank red wine compared with total abstainers.

"There is a strong correlation between moderate intake of alcohol and decreased risk of cardiovascular disease, and our data provides a mechanism for this since LDL-cholesterol was lowered to such a large extent" says Fredrik Nyström at LiU.

Fatty liver can lead to cirrhosis of the liver and is the most common liver ailment in the Western world. Roughly every fourth Swede presently has fatty liver.