Blue Light Exposure may Increase Hunger

Perhaps certain settings can affect your mood, but could colored lights alter your metabolism?

A recent study conducted by researchers at Northwestern University in Chicago, Ill., found that exposure to blue-enriched light immediately before and during dinner carries the potential to increase hunger and alter metabolism in some individuals.

"It was very interesting to observe that a single three-hour exposure to blue-enriched light in the evening acutely impacted hunger and glucose metabolism," said study co-author Ivy Cheung, a doctoral candidate in the Interdepartmental Neuroscience program at Northwestern University in Chicago, Ill., via a press release. "These results are important because they suggest that manipulating environmental light exposure for humans may represent a novel approach of influencing food intake patterns and metabolism."

For the study, researchers examined 10 healthy adults with regular sleep and eating schedules who received identical carbohydrate-rich isocaloric meals. For four days, they were required to eat under dim light, which involved exposure to less than 20 lux during 16 hours of time spent awake and less than 3 lux during eight hours of sleep. However, on the third day, they were exposed to three hours of 260 lux, blue-enriched light, with 10.5 hours after waking up. The effects were compared with dim light exposure on the second day.

As the study findings suggest that changes in certain environments could help potentially influence certain behavioral patterns, researchers note that further studies are needed in order to determine a more clear distinction of the mechanisms involved in the relationship between light exposure and hunger.

More information regarding the findings can be seen via the journal Sleep.