With Halloween, comes candy and junk food. And with that comes high energy in kids looking for more treats before they crash.

Research has shown a connection between high sugar intake and cognitive function.

In the days after Halloween, kids often go to school with their lunches filled with the candy they got while trick-or-treating. Then, they fill their bodies with all the treats, and their teachers have to manage their fluctuating energy.

At a time when studies have shown that issues in student behaviour have increased and attention spans have decreased, it can already be difficult for teachers to control their classes. Adding large amounts of sugar intake on top of that can make the job that much more challenging.

Some parents have chosen to either limit the amount of Halloween candy their child can bring to school, or not let them take any at all.

Nikki Khoury, a mother of two in Ottawa, is one of them. Her oldest daughter is six years old and currently in Grade 1.

She normally tries to fill her child’s lunch with healthy foods and says it will not be an exception for Halloween.

While she says her kids will go trick-or-treating this year, Khoury will not be letting her daughter take candy with her to school the next day.

“It affects their behavior. Definitely affects their habits,” she said.

Khoury wants to ensure that her daughter is able to pay attention in class and does not want large amounts of sugar to affect her ability to do so.

“They won’t be really focusing on what the teacher is saying, and they won’t be learning as much,” she said.

Alfonso Abizaid is a professor in Neuroscience at Carleton University. He explained in an email to the National Post how the large amounts of sugar kids may have on and after Halloween can affect them.

“The impact of these foods on these systems and others in the brain can ultimately impact learning … and reduce cognitive function, attention and motivation, thus clearly impacting a child’s performance in the classroom.”

He explained how sugary treats will activate the brain’s pleasure system which “may be expressed in hyperactivity.”

While candy may originally give kids a lot of energy, they will eventually become tired.

“It may have an impact on their ability to concentrate given that candy has highly refined sugary products … that ultimately make children go from hyperactive to sleepy,” Abizaid said.

The more tired students become, the less focused they will be, making it more challenging for teachers to be productive in their lessons.

High sugar intake can lead to “brain fog” which eLearning Academy wrote “can make it challenging for students to process information, retain knowledge, and perform at their best academically.”

Khoury acknowledges that this does not just affect her child’s health and ability to learn, but the teacher’s ability to teach and manage their classroom.

“They’re not sitting still and they’re not focusing, so it’s going to make it harder for (the teacher) to deliver the message,” she said, adding, “Or to really control them.”

While kids may appreciate the treat, it may be better to hold off on giving it to them, or at least, give them smaller amounts at a time.

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