Science

Poor Memory Again Linked To The Overweight

It appears, based on new research out of the University of Cambridge, that overweight adults may also have poorer episodic memory than their peers. Episodic memory controls the ability to recall past events and this study is another that adds evidence to a connection between the two.

Poor Memory Again Linked To The Overweight

Poor memory and the overweight?

In a study (preliminary) recently published in the The Quarterly Journal of Experimental Psychology, researchers have found a link between high body mass index (BMI) numbers and poor performance on episodic memory test.

The study by the Department of Psychology researchers, while not grand in its scale, shows that the brain’s development might be slowed to the weight of the person and leaves the brain wanting in the performance of certain cognitive tasks. Obesity has, for a some time, been linked with the hippocampus not functioning as well as it should as well dysfunction in the frontal lobe which is involved in emotional responses, problem solving and decision making. That said, there hasn’t been much of a link found between obesity and memory failings.

In the UK, where the study was conducted, about 60% of adults are overweight or obese. While those numbers are ridiculously high, they are expected to reach around 70% by 2034. Obesity has no shortage of health issues attached to it including diabetes, heart disease, depression and anxiety.

The researchers speak on the study

“Understanding what drives our consumption and how we instinctively regulate our eating behavior is becoming more and more important given the rise of obesity in society,” says Dr Lucy Cheke. “We know that to some extent hunger and satiety are driven by the balance of hormones in our bodies and brains, but psychological factors also play an important role – we tend to eat more when distracted by television or working, and perhaps to ‘comfort eat’ when we are sad, for example.

“Increasingly, we’re beginning to see that memory – especially episodic memory, the kind where you mentally relive a past event – is also important. How vividly we remember a recent meal, for example today’s lunch, can make a difference to how hungry we feel and how much we are likely to reach out for that tasty chocolate bar later on.”

The results off the study were gleaned from testing 50 participants aged 18-35 with BMIs ranging from 18 to 51. A BMI of 18-25 is considered healthy, 25-30 overweight, and over 30 obese.

The participants were given a memory test called the ‘Treasure-Hunt Task’ where they were told to hide items in certain places over two days. After two days they were asked to “dig them up” and asked where and when they were hidden. Not surprisingly, given the title of this piece, higher BMI individuals did poorer on the test compared to the health participants.

“We’re not saying that overweight people are necessarily more forgetful,” cautions Dr Cheke, “but if these results are generalizable to memory in everyday life, then it could be that overweight people are less able to vividly relive details of past events – such as their past meals. Research on the role of memory in eating suggests that this might impair their ability to use memory to help regulate consumption.

“In other words, it is possible that becoming overweight may make it harder to keep track of what and how much you have eaten, potentially making you more likely to overeat.”

“The possibility that there may be episodic memory deficits in overweight individuals is of concern, especially given the growing evidence that episodic memory may have a considerable influence on feeding behavior and appetite regulation,” she says.

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