It goes without saying that the US is currently experiencing a rapidly growing obesity epidemic. Researchers from various fields continue to look for possible causes and solutions to such a deleterious medical condition. A recent study conducted by Teegarden, Scott, and Bale seem to have advanced our understanding of obesity just a bit further.
In a 10 day macronutrient choice preference test they found that high fat diet early-exposed mice exhibited a significantly greater preference for a high fat diet later on as adults measured by daily caloric intake. As a control for diet familiarity, mice exposed to a high carbohydrate diet during early life showed no differences in adult macronutrient preferences.
Interestingly, although there was increased proportional intake of the high fat diet within the early-exposed mice, there were no differences in total caloric intake or weight gain during the macronutrient choice preference period compared to a control group. This suggests that exposure seems to impact preference only.
The authors explain that the early-exposed mice exhibited significant changes in biochemical markers of dopamine signaling in the nucleus accumbens which altered long-term programming of mechanisms important in dietary preferences and reward.
This study makes me think of the countless number of youths I've see chowing down at McDonalds (I was one of them). It's unfortunate that the parents aren't able to see the bleak distant future of their children; lined up at a drive-through eagerly awaiting that first bite of the savory double cheeseburger and one step closer to developing heart disease.
Teegarden SL, Scott AN, & Bale TL (2009). Early life exposure to a high fat diet promotes long-term changes in dietary preferences and central reward signaling. Neuroscience, 162 (4), 924-32 PMID: 19465087