(Reuters Health) – People seeking to improve their diet are likely to have less fat in their liver and lower risk of liver disease than people who stick to unhealthy eating habits, a US study found.
The researchers focused on the so-called non-alcoholic fatty liver (NAFDL), which is usually associated with obesity and certain eating habits. While dietary changes are recommended for the treatment of this type of liver disease, research has not yet clearly shown whether these changes can work for prevention.
For the current study, researchers looked at data from nutrition questionnaires and liver fat scans for 1,521 individuals who participated in the long-standing Framingham Heart Study. The participants did the questionnaires and scans twice, at least three to four years apart.
During the study, people with an above-average increase in adherence to a healthy Mediterranean diet rich in whole grains, fish, lean protein, vegetables and olive oil had a 26 percent lower likelihood of developing fatty liver disease than those with average increases in accordance, the study said found.
Above-average growth in adherence to another liver-friendly diet, known as the Alternative Healthy Eating Index, was associated with at least 21
People at high genetic risk for fatty liver disease, whose diets decreased over the study period, accumulated more fat in their livers. But even with a high genetic risk, fat accumulation did not increase as people kept or improved their diet.
"Our results show that increased nutritional quality is associated with lower liver fat accumulation and a reduced risk of developing fatty liver, especially in those with a high genetic risk for NAFLD," said senior study author Dr. Daniel Levy, director of the Framingham Heart Study and a researcher at the National Institutes of Health in Bethesda, Maryland.
Participants who had improved diet quality ratings consumed more fruits, vegetables, and whole grains containing high levels of water and fiber.
"We have speculated that these foods can reduce energy intake by affecting satiety and improving weight control and reducing liver fat," Levy said via email. "It's also possible that dietary fiber intake can affect gut bacteria and affect liver fat."
Both diets in the study also limit the intake of red meat, which can lead to liver fat and promote the consumption of foods such as nuts. which could help reduce liver fat accumulation, Levy added.
Most people have a bit of fat in their liver. A fatty liver disease can occur when more than 5 percent of the liver is fat. Excessive drinking can damage the liver and cause it to accumulate fat, a condition known as alcoholic fatty liver, but even if people do not drink much, they may still develop a nonalcoholic fatty liver disease.
The study was not a controlled experiment to show whether or how dietary changes could influence the risk of developing fatty liver disease. The researchers also relied on questionnaires to assess participants' diets, which may be unreliable, and lacked data on non-dietary causes of liver fat accumulation, including certain medications and viral infections.
Nonetheless, the findings add to the evidence that healthy eating habits can minimize the risk of fatty liver disease, even if humans have a genetic risk for the disease, said Shira Zelber-Sagi, a researcher at the University of Haifa in Israel was not involved in the study.
"Genetics is not a fate," said Zelber-Sagi by email. "Patients have the power to improve their liver health in many cases from NAFLD itself."
SOURCE: bit.ly/2r6sVG3 Gastroenterology, online March 28, 2018.