Parents might as well give their child a can of beer if they’re going to allow them to eat junk food — if some new scientific conclusions are to be believed.

According to a study conducted at the University of Southern California, rats who were fed a diet full of fat and sugar during adolescence suffered long-term memory problems that persisted well into adulthood. The study warned parents they might want to consider candy bars just as bad as beer cans.

“What we see not just in this paper, but in some of our other recent work, is that if these rats grew up on this junk food diet, then they have these memory impairments that don’t go away,” said Scorr Kanoski, professor of biological sciences at the USC Dornsife College of Letters, Arts and Sciences, in a press release.

During the study, Kanoski and postdoctoral research fellow Anna Hayes looked at prior research that showed a link between poor diet and Alzheimer’s disease. Those with the disease had lower levels of a neurotransmitter called acetylcholine in their brains, which is essential to memory and other functions including learning, arousal, attention and involuntary muscle movement.

The study, conducted on rats, involved giving some of the rodents a fatty, sugary diet. Then they tested their memory skills. Those rats that were on the junk food diet couldn’t remember objects they had previously been shown or where they were located compared to the rats that weren’t on the same diet.

“Acetylcholine signaling is a mechanism to help them encode and remember those events, analogous to ‘episodic memory’ in humans that allows us to remember events from our past,” Hayes said. “That signal appears to not be happening in the animals that grew up eating the fatty, sugary diet.”

The authors of the study said adolescence is a very sensitive period for the brain as it continues to develop, but added that more research is necessary to figure out how memory problems from a diet high in junk food may be reversible.

“The study was actually quite interesting, but I wouldn’t compare eating junk food to alcohol,” said Jalaine Kantor, a registered nurse and dietician at Intermountain Utah Valley Hospital in Provo. “I think there are some people who are addicted to junk food, but whether that’s the same process as alcohol, I don’t really know, but I do feel like there’s a whole bunch of components that go into addictions that we don’t understand. I just wouldn’t say it has the same effect as alcohol.”

Kantor said she believes the authors took some narrow pieces of the study and fit them in ways that ultimately demonize food, which she doesn’t think the study meant to do, and noted there are a few other studies that didn’t find the same results.

Kantor, who works in the pediatrics department, said the study was also done in a lab and people need to keep in mind how that actually correlates with humans.

“When you have an unhealthy relationship with food, that also becomes a problem later in life,” she said. “I have quite a few kids who come in for weight management, and nine times out of 10 the parents tell me they won’t allow a certain food, but then they find out their child has been sneaking it into their diet. When you start saying you aren’t allowed to have candy or any other type of food, we as humans naturally start to say, ‘That’s what I want now,’ and that’s all we can think about.”

Kantor said restricting food also can lead to problems later in life such as guilt issues with appearance.

“The point I like to make is that health is more than what we look like,” she said. “Can you get out of bed in the morning? Are you getting enough sleep and not waking up exhausted? Can you walk down the street without feeling out of breath? Just because you’re skinny doesn’t mean you’re healthy. I grew up in the ’80s and ’90s when they started talking about the obesity epidemic, where they just started to strictly look at the body and got away from whether the person was healthy.”

Kantor said it’s perfectly fine to incorporate a treat into your diet on occasion.

“We shouldn’t be labeling food as good or bad. If I’m going to eat pizza one night and I have a couple of slices, that’s totally fine, but if I have pizza every day? Well, that’s when we need to change our eating habits.”

Kantor said eating all goes back to moderation.

“Fill half of your plate with fruits and veggies and the other half with protein and starch and if you want dessert once in a while, then have it,” she said. “Does food affect brain development and memory? Yes, and a healthy diet can definitely have a benefit. What we eat is going to help us retain memory and help us to function and process things, but we need to understand the whole point. When we demonize one food group, it almost has a detrimental effect in the long run.”

The study was published in Brain, Behavior and Immunity.

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