Today, a staggering 40% of US adults are obese which is more than three times greater than the number in the 1970s. Obesity not only affects the daily life of an individual but also increases the risk for many diseases including type 2 diabetes, cardiovascular disease and certain types of cancer. This has resulted in an estimated 150% increase in healthcare spending, compared to non-obese individuals. One contributing factor to the prevalence of obesity is the availability of energy-rich foods at any time of the day.
Scientists, lead by Ali Güler at the University of Virginia, are investigating the effects of a high fat/sugar diet on the body’s biological clock and eating schedule. Their most recent study focuses on a subset of neurons in the brain that regulate dopamine signaling. This “pleasure chemical” is released after consumption of food, which likely motivated the survival of early humans when food was scarce. Using mouse models, the scientists showed that a high fat/sugar diet disrupts the biological clock and normal feeding schedule, leading to “any-time snacking” and obesity. This snacking and weight gain was dependent on the function of the dopamine-regulating neurons in the region of the brain controlling the biological clock.
Diets rich in fat and sugars have negative effects on the body. However, the specific effects of these diets on brain activity and biological rhythms have been less clear. This study importantly identifies a mechanism by which fat/sugar-rich foods can disturb the body’s eating schedule and lead to over-consumption. In a modern society, where food can be readily accessed, and at unnatural times of the day, it will be important to identify the factors that lead to over-consumption and obesity.
Managing Correspondent: Jeremy Gungabeesoon
News Article: Study finds dopamine, biological clock link to snacking, overeating and obesity. ScienceDaily
Original Article: Dopamine Signaling in the Suprachiasmatic Nucleus Enables Weight Gain Associated with Hedonic Feeding. Current Biology
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