You probably already know that a high fat diet can lead to a host of physical problems, but did you know that it can lead to memory impairment as we age? A new study from Ohio State University has found that just three days on a high fat diet could crush your cognitive ability if you are a senior. Here’s the (not so) skinny.
A high fat diet is known to cause metabolic changes, and we know that obesity leads to health problems such as heart disease and diabetes, but even relatively healthy older individuals could suffer memory impairment after just three days on a diet consisting of 60% fat if a trial involving rats is anything to go by, and it usually is.
How Was the High Fat Study Carried Out?
Researchers fed groups of young and old rats with a high fat diet for terms lasting between three days to three months. They then compared the results with the groups that had been eating a lower fat diet.
What Were the Results of the High Fat Diet Study?
The scientists found that independent of age, all of the rats on the 60% fat diets took on gut inflammation and metabolic problems after three months, but the older rats performed poorly on memory tests and showed concerning inflammation levels in the brain too. Alarmingly, these mental side-effects were noticeable after just three days, although they were not present in the younger rats, meaning that as we age, a high fat diet could be more problematic to our cognitive health.
For reference, a McDonald’s Double Smoky BLT Quarter Pounder with Cheese or a Burger King Double Whopper with Cheese both consist of 60% fat.
The two types of memory that showed rapid decline on the high fat diets were contextual memory and cued-fear memory. Both of these are associated with dementia. “A departure from baseline inflammatory markers is a negative response and has been shown to impair learning and memory functions,” said Ruth Barrientos, who is an investigator in the Institute for Behavioral Medicine Research at The Ohio State University.
“These diets lead to obesity-related changes in both young and old animals, yet young animals appear more resilient to the high-fat diet’s effects on memory. We think it is likely due to their ability to activate compensatory anti-inflammatory responses, which the aged animals lack.”
In terms of humans, more work needs to be done to determine what age is high risk on a high fat diet as far as our memory is concerned, but since we already know that excessive fat intake is linked to poor health outcomes, the effects that it has on our brain is another reason to re-balance our diets. And, with this emerging knowledge, we may be able to improve our mental performance as we age by reducing a reliance on fast or fatty foods. It’s certainly food for thought.
