Many behavioral disorders such as the Attention deficit hyperactivity disorder (ADHD), and aggressive behaviors are linked to sugar intake and obesity, but the cause behind this link was unknown. Now, a research team from the University of Colorado in the US managed to unveil it.
In a study published in the journal Evolution and Human Behavior, the US researchers presented evidence based on animal experiments supporting a role for fructose, the sugar found in fruits and some types of vegetables, in increasing the risk for these behavioral disorders.
The sweetening level of fructose is twice that of sucrose or cane sugar, and it is used in sweets, jams, jelly, soft drinks and juices.
"We present evidence that fructose, by lowering energy in cells, triggers a foraging response similar to what occurs in starvation.This foraging response stimulates risk taking, impulsivity, novelty seeking, rapid decision making, and aggressiveness to aid the securing of food as a survival response. Over-activation of this process from excess sugar intake may cause impulsive behavior that could range from ADHD, to bipolar disorder or even aggression," said lead author Richard Johnson, professor at the University of Colorado's School of Medicine in a report published Sunday on the university's website.
"While the fructose pathway was meant to aid survival, fructose intake has skyrocketed and led to obesity and many unwanted behavioral disorders," Johnson added.
He also explained that the production of uric acid after the metabolism of fructose may lead to some of these behavioral disorders, and the foraging response similar to what occurs in starvation could eliminate the pleasure felt after sugar consumption and trigger depression.
"We do not blame aggressive behavior on sugar, but rather note that it may be one contributor. The identification of fructose as a risk factor does not negate the importance of genetic, familial, physical, emotional and environmental factors that shape mental health," Johnson noted.