Published in the Journal of Environmental Psychology, a team of psychologists asked children to categorize a range of foods, including cheese, french fries, bacon, popcorn, shrimp, almonds, and egg. The responses threw up a number of surprises, including that 47 percent of the 176 participants believed that french fries came from animals.

Cheese was commonly misidentified as plant-based, with 44 percent incorrectly identifying its origin. 41 percent believed bacon to come from a plant (we wish) and 40 percent said the same of hot dogs. Even chicken nuggets, which famously have chicken in their name, were misidentified as coming from plants 38 percent of the time.

"Popcorn and almonds were also commonly misclassified [as animal-based], each by more than 30% of children," the team write in their report.

As well as assessing the children's knowledge of the origins of foods, the team looked at what animals and plants the kids believed could and couldn't be eaten. It appears that there is a lot of confusion about what is and isn't edible, with the majority believing that cows (77 percent), pigs (73 percent), and chicken (65 percent) are inedible. Sand was considered edible by 1 percent, five times less than the amount who believed cat to be a type of food.

The study shows that there are a lot of misconceptions around food at this early age – but the team believes it could be an opportunity.

"Most children in the United States [...] eat animal products, but unlike adults who have built up an arsenal of strategies to justify the consumption of animals, children appear to be naïve meat eaters," the team wrote in their discussion. "The current study suggests that children eat meat unknowingly, and perhaps in violation of a bias against animals as a food source. Childhood may therefore represent a unique window of opportunity during which lifelong plant-based diets can be more easily established compared to later in life."

The team believes that part of the poor knowledge could be due to parents withholding knowledge about where meat comes from, believing it to be too gruesome for children to learn at such a young age.

"Rather than manage the inconvenience of cooking several meal options or confront the emotions that may come with the revelation that the bacon on their child's plate was once a living, breathing pig, some parents instead skirt the truth altogether through vague terminology that has potentially lasting impacts on children's eating habits."

By being more open about the source of foods (i.e. telling kids how the sausage was made), and providing more meat alternatives, the team believes children may gravitate naturally towards plant-based foods.

"At the family level, youth climate activism may begin at the dinner table," the team writes.

"By refraining from eating foods that violate their beliefs about the well-being of animals, children would also be acting in a manner consistent with their moral views of the environment. In addition to reducing their own carbon footprints, children's principled eating behaviors may also influence those of their parents."