Researchers found that just 2 weeks of a carb-restricted diet reduced levels of liver fat and improved other markers of cardiometabolic health in a small number of individuals living with non-alcoholic fatty liver disease (NAFLD)
Study co-author Adil Mardinoglu, from the KTH Royal Institute of Technology in Sweden, and team recently published their results in the journal Cell Metabolism.
NAFLD is a condition characterized by an excess accumulation of fat in the liver. Unlike alcoholic fatty liver disease, NAFLD is not caused by heavy alcohol consumption.
Around 30–40 percent of adults in the United States are thought to have NAFLD, making it "one of the most common causes of liver disease" in the country.
Adopting a healthful diet is considered key for treating NAFLD, and doctors normally recommend reducing the intake of fats.
The new study, however, suggests that lowering the consumption of carbohydrates could be another treatment strategy for NAFLD.
Liver fat metabolism improved
Mardinoglu and his colleagues enrolled 10 adults, all of whom were obese and had NAFLD, to their study.
For 2 weeks, the participants were put on an isocaloric diet that was restricted in carbohydrates but increased in protein. An isocaloric diet is one wherein the same amount of carbohydrates, proteins, or fats are consumed every day.
The team assessed how the dietary intervention affected the liver fat, as well as other metabolic responses, of the study participants.
The study revealed that the carb-restricted diet improved liver fat metabolism and led to "dramatic reductions" in liver fat over the 14-day study period.
The researchers also found that carbohydrate restriction led to a decrease in inflammatory markers, particularly interleukin-6 and tumor necrosis factor alpha — higher levels of which have been linked to greater NAFLD severity.
What is more, they found that the carb-restricted diet induced changes in gut microbiota that were associated with an increase in circulating levels of folate, which has been tied to improvements in liver fat metabolism.
Commenting on their results, the researchers write:
"[...] we showed that short-term intervention with an isocaloric low-carbohydrate diet with increased protein content promotes multiple metabolic benefits in obese humans with NAFLD."
That said, they caution that there is no one-size-fits-all approach when it comes to dieting, so a carb-restricted diet may not work for everyone with NAFLD.