Being overweight can dampen your memory!

The study found a link between high body mass index (BMI) and poorer performance on a test of 'episodic memory'.

Updated: Feb 26, 2016, 21:29 PM IST

Zee Media Bureau

London: A new research suggests that young adults who are overweight may have poorer memory than their peers.

The research from Cambridge University adds to the increasing evidence of a link between obesity and memory.

The study, published in The Quarterly Journal of Experimental Psychology, found a link between high body mass index (BMI) and poorer performance on a test of 'episodic memory' - the ability to recall past experiences.

However, researchers found that other aspects of memory - such as general knowledge - were unaffected.

50 individuals aged 18-35 participated in a memory test with BMIs ranging from 18 through to 51. A BMI of 18-25 is considered healthy, 25-30 overweight, and over 30 obese.

Participants were asked to hide items around complex scenes (for example, a desert with palm trees) across two ‘days’. They were then asked to remember which items they had hidden, where they had hidden them, and when they were hidden.

Researchers found that obese people score 15% lower than thinner people. Overall, the team found an association between higher BMI and poorer performance on the tasks.

According to the researchers, the results could suggest that the structural and functional changes in the brain previously found in those with higher BMI may be accompanied by a reduced ability to form and/or retrieve episodic memories. As the effect was shown in young adults, it adds to growing evidence that the cognitive impairments that accompany obesity may be present early in adult life.

“We're not saying that overweight people are necessarily more forgetful," said Dr Lucy Cheke, from the University of Cambridge.

“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,” Dr Cheke added.

As this was a small, preliminary study, researchers caution that further research needs to be done to establish whether the results of this study can be generalised to overweight individuals in general, and to episodic memory in everyday life rather than in experimental conditions.