Turns out your hunger may be influenced by more than how long it's been since you last ate. According to a study conducted by the Interdepartmental Neuroscience program at Northwestern University in Chicago, light may also have an effect.
The study followed 10 adults, who spent two days of pre-meal exposure to dim lighting and then one day under that of a blue hue before eating. The result: Subjects showed increased hunger after only 15 minutes with the blue light. This sustained hunger lasted almost two hours after their meals. In short, eating in a low-lit diner will yield consumption of appropriate portions, while a meal in your office’s conference room or in front of the computer screen means you’re more likely to stuff yourself.
The results complement preview studies, which showed that blue light leads to a lack of sleep, and a lack of sleep can lead to an increase in hunger. But it also draws larger questions about food intake patterns and metabolism.
The study opened a door, but it's still far from conclusive. Future research could determine what long-term exposure to blue during meal time does for both hunger and sleep.
Further, music has also been linked to light and hunger. A 2012 study published in the journal Psychological Reports looked at the calorie intake of customers in an Illinois fast food restaurant after lights in a section were dimmed and music played softer. Customers ate an average of 18% fewer calories than those sitting in brighter and louder sections.