Researchers in Southampton and Rome have found excessive consumption of fructose – a sweetener found in many fizzy drinks – is strongly associated with a severe form of liver disease in children, known as non-alcoholic steatohepatitis (NASH).
Sugar, made up of fructose and glucose, is a natural substance that occurs in many foods. In a balanced diet, sugar does not cause harm. However, fructose syrups or sugar containing fructose and glucose is widely added to food and drinks – and excessive consumption may potentially cause health problems.
The five-year study, led by the University’s Professor Christopher Byrne and colleague Dr Eleonora Scorletti at the NIHR Southampton Biomedical Research Centre and Professor Valerio Nobili from the Bambino Gesu Hospital in Rome, found 40 per cent of the participants had NASH – which can cause symptoms including stomach pain and extreme tiredness in children.
In adulthood it can progress to cirrhosis and liver cancer, requiring liver transplantation. Patients with high levels of fructose consumption in the study also had higher levels of uric acid, which is known to cause gout in adults.
Almost all participants in the study regularly consumed morning (95 per cent) and afternoon (89 per cent) snacks. In the morning these consisted largely of crackers, pizza and salty foods, while afternoon snacks included biscuits and yogurt.
Around 90 per cent had fizzy or soft drinks at least once a week. The average daily intake of fructose among patients with NASH was 70 grams, compared to 53 grams in children and teenagers without the condition.
Professor Byrne commented:
Given the popularity of sugary drinks and snacks containing a lot of sugar, many children are eating too much fructose each day. Unfortunately, for every gram over the daily requirement, the risk of developing serious liver disease increases one and a half times.
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.
This data emphasises the importance of parents ensuring that their children consume sugary drinks, snacks and sweets in moderation.