A leading neuroscientist says that while eating highly processed junk food negatively affects the brains of children, current scientific evidence does not support the myth that sugar makes kids hyperactive.

According to Study Finds, Amy Reichelt, a nutritional neuroscientist at the University of Adelaide, says that while sugar may provide an energy boost, it does not turn children into hyperactive whirlwinds. She claims that myth began in the 1970s and early 1980s when the Feingold Diet purported to manage symptoms of attention deficit disorder, or ADHD, and autism by eliminating certain foods, including sugar.

The diet has since been widely criticized by the medical community for its lack of scientific evidence, strict rules and dangers. It eliminates artificial colors, sweeteners (including sugar), substances known as salicylates and certain preservatives. Dr. Benjamin Feingold, a California-based pediatrician, believed that avoiding these ingredients, as well as a few other foods, improved focus and behavior.

Despite some anecdotal evidence, scientific research has not supported that the diet improves behavioral problems in kids with ADHD or other conditions. Reichelt says that salicylates are found in many healthy foods including tomatoes, broccoli, cucumbers, nuts and seeds. Therefore, the Feingold diet eliminates many foods that are necessary for healthy development. The studies that Feingold performed were flawed, says Reichelt, and since that time rigorous research has failed to find a connection between sugar and hyperactivity.

Reichelt says that the increased activity in children when sugar is present may be due to dopamine released by the brain. The neurotransmitter is released when a reward is encountered, she says, which could be a sugary treat. Dopamine function is linked to ADHD, says the expert, and many of the drugs prescribed to treat ADHD help increase dopamine levels in the brain to aid focus and behavioral control.

Other studies have demonstrated that when parents expected their children to be hyperactive after consuming sugar, they perceived this effect, even if the kids had consumed a placebo, sugar-free product.

The World Health Organization recommends limiting free sugar consumption to less than 10% of daily calories, even down to 5% for greater health benefits. Free sugars include sugars that have been added to foods during the manufacturing process and those already present in foods like honey, syrups and fruit juices.

Reichert suggests that parents offer non-sugar rewards, such as stickers and toys or a fun activity, for positive behavior.