Over the past several decades, nonalcoholic fatty liver disease (NAFLD) – a disease of fat metabolism in the body that results in excess storage of fat in the liver – has grown from being rare in children to the most common reason they are referred to specialty liver clinics.

With a team of supporting researchers, Miriam Vos, MD, MPH, Pediatric Hepatologist at Children’s and Professor of Pediatrics at Emory, is studying the clinical needs of this condition, including better diagnostics, therapeutics and prevention. While it is well established in the scientific literature that diet plays a major role in NAFLD, which nutrients make the most difference, and how fat is increased and decreased, is not as well understood.

NAFLD research team: Karla DeSantos RD, Julia Tisheh, Meera Shah, MD, Jean Welsh, RN, MPH, PhD, Miriam Vos, MD, MPH, Risha Nayee, MPH, Elizabeth Sinclair, RD and Irene Pyo.

To shine a light on the key nutrients involved, Dr. Vos and her team conducted a study in collaboration with Jeffrey B. Schwimmer, MD, of the University of California at Berkeley, to determine if children who have NAFLD can reduce their liver fat if placed on a very low sugar diet.

With funding from the National Institute of Diabetes and Digestive and Kidney Diseases of the NIH, the investigators studied adolescent boys diagnosed with NAFLD and followed them for eight weeks. Half of participants were assigned a very low sugar diet and the other half remained on their usual diet. The researchers then measured how much new fat was being made within the liver, both before and after the very low sugar diet.

Results showed that synthesis in the liver of new triglycerides, a type of fat the body makes or obtains from food, decreases significantly when dietary sugars are reduced. Findings also demonstrated that a decrease in fat synthesis was most likely responsible for the decline in liver fat. Furthermore, insulin resistance and weight both improved in parallel with decreased fat synthesis. The study confirmed the pathological link between NAFLD and excessive sugar in the diets of children and was published in the Journal of Clinical Investigation.

Because of the high-impact results, Dr. Vos and co-investigator, Jean Welsh, PhD, RN, MPH, Research Director of Children’s Strong4Life and Associate Professor of Pediatrics at Emory, received a five-year $2.5 million grant from the NIH’s National Institute of Nursing Research to conduct a new prevention-based study to test if reducing sugar earlier in childhood can diminish the onset of NAFLD, or reduce the severity of the disease in children who are highly susceptible due to genetics.

“As difficult as it is to for a child or teen to significantly limit their sugar consumption, these findings suggest that doing so may one day reduce the number patients we see with fatty liver disease,” says Dr. Vos. “After a decades-long rise in those patients, that would be a great day.”