There's been plenty of proof that obesity can negatively affect a person's health. And now there's one more addition to the list. Being overweight is associated with poor memory.
In a small-scale study at the University of Cambridge, researchers found that young adults with a higher body mass index have poorer episodic memory than their peers.
Episodic memory is a person's unique memory of a specific event. This doesn’t necessarily mean that overweight people are more oblivious. But generalizing the results of the study to memory in everyday life, it can be concluded that obese people are less able to vividly remember details of past events, including past meals. This might spoil their ability in using memory to regulate food intake.
"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," said Dr Lucy Cheke, from the university's Department of Psychology.
"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."
"We're not saying that overweight people are necessarily more forgetful," said Dr Cheke, "but if these results are generalisable 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."