Eating too much fructose - a common type of sugar - puts children at greater risk of fatty liver disease, shows new research from the NIHR Southampton Biomedical Research Centre.
This new study, led by Professor Christopher Byrne, has shown that excessive consumption of the sugar fructose is not only fuelling childhood obesity, but may also be damaging their livers.
Fructose is a natural sugar found in many foods, especially in fruits but also in vegetables and flour used for pasta, bread and pizza. In a balanced diet, eating fructose contained naturally in foods such as fruit does not cause any harm.
However, high fructose syrups and sweeteners that are widely used in sugary drinks, fruit juices, jams and sweets have an artificially high sugar content. Just one 500ml bottle of cola can contain 14 sugar cubes worth, double the recommended daily amount for children.
Given these high levels and the popularity of these drinks and snacks, many of children are eating an excess of fructose each day. Unfortunately, for every gram over the daily requirement, the risk of developing serious liver disease increases one and a half times.
Liver disease and fructose
Over 271 children and teenagers with fatty liver disease at the Bambino Gesù Children’s Hospital in Rome took part in the five year study, with almost 40% having advanced liver disease.
Children who ate and drank more fructose had high levels of uric acid in their blood, and were more likely to have the serious and advanced form of fatty liver disease.
A build up of uric acid occurs when excess fructose is broken down by the liver. Too much uric acid can be toxic to the body, contributing to diseases such as gout and kidney disease.
The study results, published in the Journal of Hepatology, show that high levels of uric acid may also contribute to liver damage and the development of a serious form of fatty liver disease in children.
“Several studies have shown that high consumption of sugar (containing fructose) is associated with a number of conditions in childhood such as obesity and type 2 diabetes. However, little was known of its effect on the liver until now,” explains Professor Byrne.
“Our results suggest that too much sugar consumption may be harmful for the child’s liver because of the link between high fructose consumption and serious liver disease. The data emphasise the importance of parents ensuring that their children consume sugary drinks, snacks and sweets in moderation.”