Junk food teens could face long-term memory problems
Teens who eat a junk food diet high in fat and sugar could suffer from long-lasting brain damage – specifically memory impairment, according to a recent study done on rats from the University of Southern California.
Researchers fed rats a high-fat diet, then ran them through a series of memory tests and tracked their levels of a neurotransmitter that is related to memory and learning.
“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,” Scott Kanoski, a professor of biological sciences at the USC Dornsife College of Letters,
Arts and Sciences, says in a USC press release. “If you just simply put them on a healthy diet, these effects, unfortunately, last well into adulthood,” he adds.
The study used existing research on Alzheimer’s disease, a type of dementia that impacts thinking, behaviour and memory, according to the Alzheimer’s Association.
People with Alzheimer’s have lower levels of a brain neurotransmitter called acetylcholine, which plays an important role in involuntary muscle movement, arousal, learning and attention. The research team studied the acetylcholine levels in rats on a fatty and sugary diet compared to rats in a control group by tracking their brain responses to memory-testing activities such as finding a new object in a different location.
Rats in the control group were able to recognise new objects whereas rats in the junk food group couldn’t remember them.
Kanoski says that adolescence is a time when the brain is developing, so they wondered about the impact of an unhealthy western diet on brain development – and whether or not the effects are reversible.
“I don’t know how to say this without sounding like Cassandra and doom and gloom,” Kanoski explains.
“But unfortunately, some things that may be more easily reversible during adulthood are less reversible when they are occurring during childhood.”
In another round of the study, Kanoski says they were able to reverse memory damage when giving rats certain medications that mimicked acetylcholine.
When the medication was given to the part of the brain that controls memory, called the hippocampus, rats’ memory was restored.
Kanoski says more research is needed to find out how the damage can be reversed without medication.
Junk food is more than bad for brain health. A recent study found a link between ultra-processed foods and more than 30 health complications including depression, sleep disturbances and death related to cardiovascular disease.