Reducing fructose intake may reverse fatty liver disease in children
Complex childhood diseases – Fatty liver disease
Fatty liver is the most common liver disease in North America. It increases your risk of dying from a major cardiovascular event — or of developing diabetes — roughly tenfold. It also makes you five times more likely to die from liver disease. A quarter of Canadian adolescents are at risk.
Fatty liver disease is a particular concern when it begins early in life, says pediatric gastroenterologist Dr. Jason Yap. “The disease itself is cumulative. The longer you have it, the higher the risk that you will have issues.” Dr. Yap and his colleagues are looking to improve strategies to help youngsters reverse the condition.
The disease — as the name suggests — is caused by the build-up of excessive fat in liver cells. Excessive alcohol consumption can cause fatty liver, but for adolescents the cause is almost always obesity.
Dr. Yap’s young patients may not consume alcohol, but they do consume a great deal of fructose — a type of simple sugar that appears to be particularly important in the development of non-alcoholic fatty liver disease.
“In a previous experiment, when healthy people were given significant quantities of fructose they developed all the signs of fatty liver disease,” says Dr. Yap. “Their blood pressure went up. They developed hyperlipidemia — so their cholesterol and triglycerides were high — even though they were previously healthy.“
Soft drinks are the most obvious culprits when it comes to fructose, but if you read food labels you’ll discover they’re just the tip of the iceberg, says Dr. Yap. “When you go to the supermarket, you can pick up something that you don’t expect to have sweet stuff in it, for example, pre-manufactured sausage. You look at the labelling, and it actually contains high-fructose corn syrup.”
Dr. Yap is currently working on what he calls a FLY study — fructose lowering in youths — to see if eliminating the sugar might be a useful first strategy in addressing fatty liver. “We put patients on a very specific low-fructose diet. Then we measure the energy utilization of the liver by p31 MRS [magnetic resonance spectroscopy].”
“In the pilot study, the kids actually have improved blood pressure. They have changes in their body composition. They have improved liver function tests. Now that we’ve completed the pilot study, we want to do a larger study to confirm these findings.”
For patients who may feel overwhelmed with the challenge of losing weight, Dr. Yap hopes fructose reduction provides a realistic starting point. “If you tell a patient, ‘for the moment, the only thing I want you to focus on is to reduce the amount of fructose in your diet,’ it’s a lot easier to achieve.”
Through the generous support of the Stollery Children’s Hospital Foundation, WCHRI was able to provide subsidized expert biostatistical resources to Dr. Yap to assist with his studies.