SCIENTISTS think that sugar overload may be a recipe for long term health problems, especially with children who are allowed to eat too much of the sweet stuff too young.
A trial using mice has shown that a diet high in sugar from childhood could lead to significant weight gain, persistent hyperactivity and learning impairments.
They found that many people on western diets consume four times the recommended amount of sugar.
Reducing sucrose intake in mice by four-fold prevented sugar-induced increase in weight gain, supporting the World Health Organisation's recommendations of 25g per person a day.
The Queensland University of Technology study found a reduced risk of sugar-induced weight gain and other health problems when mice were given a much smaller daily dose of sucrose.
One of the lead authors, QUT neuroscientist Professor Selena Bartlett, said many children, adolescents, and adults in more than 60 countries, including Australia, had high sugar diets.
"More work needs to be done in the investigation of the long-term effects of sugar on adolescents and adults but our results with the mouse model are very promising," Professor Bartlett said.
"Obesity and impulsive behaviours caused by poor dietary habits leads to further over-consumption of processed food and beverages but the long-term effects on cognitive processes and hyperactivity from sugar over-consumption, beginning at adolescence, are not known.
"Our study found long-term sugar consumption (a 12-week period with the mice which started the trial at five weeks of age) at a level that significantly boosts weight gain, elicits an abnormal and excessive stimulation of the nervous system in response to novelty.
"It also alters both episodic and spatial memory. These results are like those reported in attention deficit and hyperactivity disorders.
"Human trials would need to be done but it suggests a link to the long-term over-consumption of sugar, beginning at a young age, which occurs more commonly in the western diet and an increased risk of developing persistent hyperactivity and neurocognitive deficits in adulthood."
Professor Bartlett said while the idea of sugar addiction and classification of sugar as an abuse substance was being debated, there was increasing evidence of overlap in the brain circuitry and molecular signalling pathways involved in sugar consumption and drug abuse.
Data suggested that sugar-induced obesity might play a role in ADHD-like symptoms in western countries.
"In children, high sugar consumption correlates with hyperactivity and in adults, with inattention and impulsivity," she said.
"What has been unclear though, is whether chronic overconsumption of sucrose - starting from childhood - would have the same negative impact on our nervous system, emotions or cognition throughout adulthood as other addictive drugs.
"This study on mice goes a long way to resolving that question."
