New Study Shows Link Between Obesity And Poor Memory

A link between obesity and poor episodic memory has been found, according to a study conducted by The Quarterly Journal of Experimental Psychology. A test of 50 people identified as “overweight” has returned results indicating that those with a higher BMI have a diminished capacity to remember single instance experiences.

The abstract for the study makes the point that obesity is an international epidemic, associated with a multitude of physical, cognitive, and psychological dysfunctions. The shortening of life expectancy and the associated increase in the cost of healthcare in developed and developing nations is cited as a reason for the importance of the research. While the effect of obesity on memory has been studied in the past, results have been mixed. This study, however, focused on episodic memory, rather than the kind of memory that is associated with early life recall or general knowledge.

Obesity effects memory
Obesity is an international epidemic.
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Episodic memory has to do with the memory of a single incident, and the vividness of that memory. A good example would be recalling a meal eaten earlier in the day. A typical memory would include sensory information of various intensity and details about what was eaten and how much. In the most recent test, it was found that people with significantly unhealthy BMI were markedly poorer at this kind of episodic memory.

In the study, participants were asked to participate in what basically amounted to a one-person “treasure hunt”, where they would be required to hide a series of objects on a computer screen and then attempt to recall where they had been placed. Obese participants performed significantly worse at this task, leading researchers to conclude that there may very well be a link between obesity and a degradation in episodic memory. At the end of the study, it was determined that thinner people were up to 15 percent better at exercising this kind of memory.

obesity effects memory
It is possible that obesity is worsened by a failure to vividly remember meals.
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It’s important to note that at no stage were amnesiac or other “blackout” symptoms observed. There was, however, a measurable diminution in the detail and intensity of memories of this kind for the obese subjects. This has led some scientists to wonder if a part of obesity’s “downward spiral” could have to do with memory. If a person becomes less able to remember vividly or in detail meals that they have already had, this may have a role to play in the regulation of appetite. It has already been found, for example, that multi-tasking while eating can lead to eating larger servings or eating more frequently. Dr Lucy Cheke of Cambridge University told the BBC that memory may have an important part to play in an individual’s efforts to control their food intake.

“If they have a less strong memory of a recent meal, with a less strong impact in the mind, then they may have less ability to regulate how much they eat later on.”

obesity effects memory
Obesity has already been linked to a wide range of cognitive dysfunction.
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Dr. Cheke and others were quick to point out the small size of the sample and the fact that this research is at a very early stage. A sample size of 50, and the fact that the results are indicative rather than conclusive, led her to point out that we’re still a long way from being at the stage where formal health advice could be issued on the basis of the findings.

The caution of scientific rigor aside, though, it seems that it is possible that the mind has a larger part in the regulation of appetite and food cravings than originally thought. The old dictum of chewing one’s food carefully and paying attention to what one is eating may indeed be sound health advice after all.

[Photo by John Moore/Getty Images]