A “small” preliminary study just published in the Quarterly Journal of Experimental Psychology appears to confirm a correlation between obesity and cognitive function that the BBC reports to have been noted in prior experiments.
A team of researchers in the Department of Psychology at Cambridge University in England carried out tests on fifty people, asking them to perform memory tasks in order to gauge their performance. Subjects of the study had Body Mass Index (BMI) scores ranging from eighteen (considered healthy) through to fifty-one (classed as very obese) and were asked to “hide” objects in different times and places on a computer simulation over a period of two days. They were then tested to see how accurately they could recall hiding the objects in the “Treasure-Hunt Task”. Overweight participants were shown to have poorer “episodic memory” than those of slimmer build.
While it has been established that hunger hormones are largely responsible for dictating how much we eat, psychology also plays a key role. For example, people who watch TV while they eat have in previous tests been found to consume more food, or feel hungrier sooner after eating, than those who do not. The researchers in this recent study suggest that the ability to remember the last meal we ate can influence how hungry we feel, and consequently how much we eat. Overweight people scored fifteen percent lower in the memory tests than skinnier ones did. If obese people are less able to keep mental track of the amount of food they consume they may be more likely to eat more than they need.
The University of Cambridge’s Dr Lucy Cheke was quoted by EurekAlert as having said that Body Mass Index negatively effected participants’ ability to remember where they hid objects during the test, but that the level of memory loss was fairly minor and certainly not so serious that it could be classed as amnesia:
The suggestion we’re making is that a higher BMI is having some reduction on the vividness of memory, but they’re not drawing blanks and having amnesia.
Dr Cheke added, however, that the memory impairment could be severe enough to cause over-eating. A study last year also suggested a connection between body weight and the likelihood of developing Alzheimer’s disease.
