An Australian former paramedic is cautioning parents against treating kids under 4 to marshmallows due to choking risks.

In a video posted online last week, Nikki Jurcutz explained that the pillowy candy’s “round shape means they could completely block off the entire airway.”

“When [marshmallows] are wet, they become sticky and more difficult to swallow and be more difficult to clear from the airway,” she continued, demonstrating with a clear plastic tube.

Jurcutz, who runs the child safety organization Tiny Hearts Education, shows how easily a grape can be freed from the tube, which is meant to mimic a child’s airway, and how stuck a chunk of marshmallow can become.

She advises parents to cut large marshmallows into smaller pieces or to “swap out for mini marshmallows instead.”

According to the Centers for Disease Control and Prevention, hard or chewy candies can be choking hazards, as can corn kernels, uncut cherry or grape tomatoes, pieces of hard vegetables and fruit, melon balls, dried fruit, nuts, seeds, string cheese and more.

“I have witnessed a child (not mine) choking on a marshmallow and I will never forget the look of fear on his face as he was unable to breathe,” one user commented on Jurcutz’s video, per The Mirror. “Luckily with [back] blows it cleared but they are a big no for me.”

“So glad you posted this, I feel like I get looked at weird when I’m hesitant to feed my two-year-old marshmallows,” another added. “‘But they are soft, they melt in the mouth’ is the response I get, I can’t explain it better than this video.”