Health researchers from Yale have made a new discovery and with it a new condition that causes, or is linked with, obesity. The study was reported in the journal Current Biology.
Yale School of Medicine found that some obese women have what they call a “food learning impairment”. But what does this mean?
Researchers showed women a sequence of food picture cards and then asked them to recall each food that they saw and to predict what foods were coming up next in the sequence. The women were divided into two groups; a group of 67 women of a healthy weight and a group of 68 obese women.
The study showed that overweight women remember more unhealthy and junk food in the sequences and more often predicted that it would appear. Obese women overestimated how often pretzels and chocolate showed in the cards.
Lead researcher and author Prof Ifat Levy said: “This is not a general learning impairment, as obese women had no problem learning when the reward was money rather than food.
“An intriguing possibility is that, by modifying flawed association between food and environmental cues, we may be able to change eating patterns.”
Researchers do not currently know how or why this happens but as there was a significant link between obesity and the ability to remember what foods were being offered, the scientists believe that there is something that is actually causing obesity in these people, so they have called it a “food learning impairment“.
The study also found that men do not follow show signs of this condition; it seem to only affect women. However, it should be noted that the study only looked at a relatively small number of women so the results, although significant, are not necessarily conclusive. Also, because the study did not determine why this trend happens there is nothing new that we can currently do to try to tackle it.
The research paper concluded with the following statement: “Rather than target these individuals’ behaviour with food, we suggest that a successful intervention should aim to modify their interactions with other cues that determine their eating patterns.”
They also said that “These findings suggest that obesity may be linked to impaired reward-based associative learning and that this impairment may be specific to the food domain.”
The report highlighted that:
- Obese women are impaired in associative learning with food reward
- Both acquisition of learning and updating of learning are impaired
- No such impairments are observed when money serves as reward
We should also note that while it is largely assumed that some mental mechanism is causing obese women to predict the presence of more food and that this somehow results in overeating, there is a possibility that being obese causes the mental impairment that the study revealed.
Reference
“Impaired Associative Learning with Food Rewards in Obese Women” by Zhihao Zhang, Kirk F. Manson, Daniela Schiller, Ifat Levy.
News source: http://www.bbc.co.uk/news/health-28348368