By Will Boggs MD
NEW YORK (Reuters Health) - 22/1/2019
Adolescent boys on a "low free sugar" diet show significant improvements in nonalcoholic fatty liver disease (NAFLD), according to results from an 8-week randomized clinical trial.
Free sugars are those added to foods and beverages and occurring naturally in fruit juices, researchers explained January 22 in JAMA.
"Reducing sugar in foods and drinks is an effective treatment for children with NAFLD and should be included as part of their treatment plan," Dr. Miriam B. Vos from Emory University, Atlanta, Georgia told Reuters Health by email. "Longer studies will be needed to test if it works beyond 8 weeks and if it can 'cure' NAFLD."
Pediatric guidelines recommend lifestyle modification to improve diet for patients with NAFLD, but they don't specify a particular diet. Growing evidence implicates dietary sugars, which account for up to 17% of calories consumed by children and adolescents in NAFLD.
Dr. Vos and colleagues investigated the impact of free sugar restriction to less than 3% of daily calories (versus usual diet) on hepatic fat content in their open-label, randomized trial of 40 adolescent boys (mean age, 13 years) whose baseline free sugar intake amounted to 10% (intervention group) or 11% (usual diet group) of total calories.
At week 8, free sugars continued to contribute 10% of daily calories in the usual diet group but contributed only 1% of daily calories in the intervention group, with 18 of 20 participants in the intervention group reporting consumption of less than 3% for free sugars during the intervention.
The mean decrease in hepatic steatosis (as measured by MRI proton density fat fraction (MRI-PDFF)) from baseline to week 8 was significantly greater for the intervention group (from 25% to 17%) than for the usual diet group (from 21% to 20%).
Among secondary outcomes, mean levels of alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase were significantly lower in the intervention group, as were mean total cholesterol levels.
During the study, the intervention group lost a mean 2.0 kg relative to the control group. While change in weight correlated moderately with change in MRI-PDFF, the greater improvement in hepatic steatosis in the intervention group persisted after adjustment for the difference in weight change between the groups.
There were no study-related adverse events.
"While this study is too short to tell us if a low-sugar diet can treat NAFLD over the long term, it does tell us that reducing sugar is beneficial in the short term," Dr. Vos said. "I think these can be used in the clinical setting as an initial treatment for all boys with NAFLD. We don't expect differences between boys and girls in response to a low-sugar diet, so it would be reasonable to use a low-sugar diet with girls as well."
She added, "In this study, we provided all the food for the children and families on a low-sugar diet because it is very hard for patients to make this type of change on their own. We will need collaboration from the food industry, from schools, and from state and federal health agencies to reduce sugar in the food that is provided to children and to design education programs to help parents understand where to find the hidden sugars."
SOURCE: http://bit.ly/2AXTnHX JAMA 2019.