That’s the conclusion from a study out of Umea University in Sweden in which scientists used magnetic resonance imaging (MRIs) to monitor the brain activity of a group of 20 older, overweight women as they underwent a series of cognitive tests.
What they found was that memory skills showed significant improvement after the subjects were put on a six-month diet and lost weight, a finding which shows that obesity-related impairments in memory function are reversible, authors say.
Previous research has shown that obese people have impaired episodic memory, the memory of events that happen throughout one’s life.
A 2010 study out of Northwestern Medicine in the US, for example, found that memory loss was proportional to how much a woman weighs and even differs depending on whether or not subjects are pear or apple-shaped.
The more weight she carried around her hips, or the more pear-shaped she was, the more pronounced the memory loss compared to women who carry excess fat around their waists, the study found.
"The altered brain activity after weight loss suggests that the brain becomes more active while storing new memories and therefore needs fewer brain resources to recollect stored information," said lead author Andreas Pettersson of the Swedish study.
The latest findings were presented recently at the Endocrine Society’s 95th Annual Meeting in San Francisco.
The cognitive tests, meanwhile, involved pairing faces and names presented on a screen as researchers examined subjects’ brain activity on MRIs, a process known as œencoding.
The memory retrieval task involved pairing the face with the first letter of their names.
After weight loss, brain activity increased during the memory encoding exercises in regions important for identification and the matching of faces, researchers said. Brain activity also decreased in areas responsible for impaired episodic memories, indicating more efficient retrieval.
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