Sugar Overload May Be a Recipe for Long-Term Problems

Summary: Higher sugar diets during childhood increase the risk for obesity, cognitive impairments, and attention deficits as adults, a new study reports.

Source: Queensland University of Technology

Children who consume too much sugar could be at greater risk of becoming obese, hyperactive, and cognitively impaired, as adults, according to the results of a new study of mice led by QUT and published by Frontiers in Neuroscience.

The study resulted in a reduced risk of sugar-induced weight gain and other health problems when the mice were given a much smaller daily dose of sucrose, supporting World Health Organisation calls for a reduction in sugar intake by humans.

One of the lead authors, QUT neuroscientist Professor Selena Bartlett, says many children, adolescents, and adults in more than 60 countries, including Australia, have a diet consisting of more than four times the sugar (100g) recommended by the World Health Organisation (25g per person per day).

“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,” said Professor Bartlett.

“Recent evidence shows obesity and impulsive behaviours caused by poor dietary habits leads to further overconsumption of processed food and beverages but the long-term effects on cognitive processes and hyperactivity from sugar overconsumption, beginning at adolescence, are not known,” said Professor Bartlett.

“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 overconsumption 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 concept of ‘sugar addiction’ and the classification of sugar as a substance of abuse were still being debated, there is increasing evidence of overlap in the brain circuitry and molecular signalling pathways involved in sugar consumption and drug abuse.

“People consume sugar and food to regulate energy balance, but also for pleasure and comfort. This hedonistic desire for palatable food is reward-driven and overeating can impact upon and even override our ability to regulate,” Professor Bartlett said.

“It is increasingly considered that unrestricted consumption of high-sugar food and beverages within the Western Diet might be linked to the increased obesity epidemic. A strong association between attention-deficits/hyperactivity disorders and being overweight or obese have also been revealed.

“Taken together, these data suggest that sugar-induced obesity may participate to the developing pathogenesis of ADHD-like symptoms in western countries. In children, high sugar consumption correlates with hyperactivity and in adults, with inattention and impulsivity.

This shows a giant gummy bear
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. Image is in the public domain

“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. Our results show for the first time that long-term consumption of sucrose leads to significant weight gain and produces persistent hyperactivity and learning impairments.”

Co-lead author Dr Arnauld Belmer added that while the overall sugar consumption has dropped since the mid-1990s, obesity rates have climbed.

“This rise in obesity rates could result from a delayed effect of excess sugar, suggesting that adult obesity may be driven by high sugar intake over a life span,” Dr Belmer said.

“Interestingly, our investigation with the mice found reducing the daily sucrose intake four-fold did prevent sugar-induced increase in weight gain, supporting the WHO’s recommendation to restrict sugar intake by this amount would be effective. It could also limit the other negative consequences including hyperactivity and cognitive impairment.”

About this neurodevelopment and diet research news

Source: Queensland University of Technology
Contact: Amanda Weaver – Queensland University of Technology
Image: The image is in the public domain

Original Research: Open access.
Long-Term Overconsumption of Sugar Starting at Adolescence Produces Persistent Hyperactivity and Neurocognitive Deficits in Adulthood” by Selena Bartlett et al. Frontiers in Neuroscience


Long-Term Overconsumption of Sugar Starting at Adolescence Produces Persistent Hyperactivity and Neurocognitive Deficits in Adulthood

Sugar has become embedded in modern food and beverages. This has led to overconsumption of sugar in children, adolescents, and adults, with more than 60 countries consuming more than four times (>100 g/person/day) the WHO recommendations (25 g/person/day). Recent evidence suggests that obesity and impulsivity from poor dietary habits leads to further overconsumption of processed food and beverages.

The long-term effects on cognitive processes and hyperactivity from sugar overconsumption, beginning at adolescence are not known. Using a well-validated mouse model of sugar consumption, we found that long-term sugar consumption, at a level that significantly augments weight gain, elicits an abnormal hyperlocomotor response to novelty and alters both episodic and spatial memory.

Our results are similar to those reported in attention deficit and hyperactivity disorders. The deficits in hippocampal-dependent learning and memory were accompanied by altered hippocampal neurogenesis, with an overall decrease in the proliferation and differentiation of newborn neurons within the dentate gyrus.

This suggests that long-term overconsumption of sugar, as that which occurs in the Western Diet might contribute to an increased risk of developing persistent hyperactivity and neurocognitive deficits in adulthood.

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  1. Sugar, apart from the naturally occurring types found in some foods, in any amount is the recipe for disaster. That includes for children, adults and anyone inbetween. It affects insulin levels and this eventually effects arteries and the heart. 60 years ago, we used to eat 30-40 lbs of added sugar on average on a yearly basis. Today, those numbers are well over 150 lbs. And thus, heart disease is the number one killer in the country.

    Way back in the 1950’s and 1960’s, many studies were finding that sugar could lead to heart disease, depending on the amounts and the individual’s bodily make-up. This info was deeply suppressed by the sugar industry through lobbying and other methods.

    Instead, heart disease was blamed on too much fats and cholesterol. Now we know that cholesterol is not the main culprit in heart disease. Never mind that at least 50% of people suffering heart problems have cholesterol levels at or below those recommended by most doctors.

    There are about a dozen types of cholesterol and these can be deciphered by using an NMR lipid profile test that also tells us the size of the cholesterol molecules, which is more important than how much is present. Your triglycerides/HDL ratio is a better predictor of possible heart problems than just using LDL levels. A ratio above 2 increases the probability of heart trouble.

    Big pharma could never dream up a drug to combat excess sugar, but they have dreamed up statins. For most people, statins are a waste of time and will not extend life or prevent heart attack related events. They will deplete your body of COQ-10, which is a substance your heart requires to keep on functioning. Amazing! A drug that pretends to help your heart actually does the opposite.

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