Increasing
the amount of protein in the diet may reduce the liver’s fat
content and lower the risk of diabetes in people with nonalcoholic
fatty liver disease (NAFLD), according to a study to be published
soon in the American Journal of Physiology—Endocrinology and
Metabolism.
NAFLD—sometimes
referred to as a “fatty liver”—occurs when more than five per
cent of the liver’s weight is made up of fatty tissue.
Excessive
fat in the liver can lead to scarring, which may increase the risk of
liver cancer or liver failure.
People
with NAFLD are more likely to develop type 2 diabetes, and people
with type 2 diabetes are more likely to develop NAFLD. In fact an
estimated 70 percent of people with type 2 diabetes also have a fatty
liver.
Obesity
is also a major risk factor for NAFLD.
Previous
studies have found that short-term protein supplementation helps
reduce the fat content in the liver, but there have been few studies
on the long-term effects of protein on NAFLD.
Researchers
conducted a two-year study to determine the long-term impact of
dietary protein on a fatty liver after weight loss.
Twenty-five
adult volunteers—15 of them previously diagnosed with
NAFLD—participated in a low-calorie diet for eight weeks to lose up
to eight percent of their body weight.
After
weight loss, the volunteers were directed to maintain their weight
for two years and to follow either a moderate- or high-protein diet
averaging from 0.8 to one gram of protein per kilogram (2.2 pounds)
of body weight.
After
two years maintaining their weight loss, the increase in dietary
protein was associated with reduced liver fat content in the
volunteers. In addition, more than half of the participants who were
previously diagnosed with NAFLD no longer had a fatty liver.
“These
findings stress the clinical implications and potential benefits of
increased protein intake after weight loss for people with NAFLD at
risk to develop diabetes,” the researchers wrote.
