Hyperactive disorders could be rooted in an human foraging instinct triggered by eating fructose-loaded foods like biscuits and ice cream, a study has suggested.
University of Colorado researchers have argued that low levels of fructose trigger a pathway that promotes foraging and the storage of energy as fat.
However, in excessive amounts, the same pathway becomes hyperactive — leading to cravings, impulsivity and aggression that increases the risk of behavioural issues.
These include ADHD, manic depression and bipolar disorder, the team said.
Fructose — or fruit sugar — is found naturally in many plants and honey, but has become more common in modern diets through refined sugar and corn syrup.
Food and drinks containing high levels of fructose today include ice cream, cookies, cakes, apples, grapes, fruit juices, peas, sugary beverages and fruit yoghurts.
In fact, it is estimated that our fructose intake has increased 40-fold since the 18th century — potentially also explaining modern incidences of diabetes and obesity.
While a small amount of sugar daily is fine, according to the World Health Organisation, most people in the UK still consumer too much.
This motivated the introduction of the so-called 'sugar tax' on soft drinks, which came into force in April 2018.
Hyperactive disorders could be rooted in an human foraging instinct triggered by eating fructose-loaded foods like biscuits and ice cream, pictured, a study has suggested
'Behavioral Disorders are common and are associated with obesity and western diet,' wrote paper author Richard Johnson of the University of Colorado and colleagues.
'Excessive intake of fructose in the form of high fructose corn syrup and refined sugars may largely contribute to these conditions.'
'Identification of fructose as a risk factor does not negate the importance of genetic, familial, physical, emotional and environmental factors that shape mental health.'
However, he added, 'we propose that excessive intake of fructose present in refined sugars and high fructose corn syrup may have a contributory role in the pathogenesis of these conditions.'
'We do not blame aggressive behaviour on sugar, but rather note it may be one contributor.'
In their paper, the team reviewed previous studies into fructose and its impact on the human body to develop their case.
'Fructose, by lowering energy in cells, triggers a foraging response similar to what occurs in starvation,' the researchers explained.
'This foraging response stimulates risk taking, impulsivity,