If you eat your dinner in a romantic, dimly lit restaurant, you'll probably end up ordering something full of calories, whereas if you're ordering in a brightly lit room, you will choose much healthier food.
The researchers already knew that eating under low, atmospheric lighting makes us eat slower, so they decided to test whether lighting has any other effects. They first surveyed 160 diners in restaurants, half of whom were seating in brightly lit room. The team then followed up with four further studies in the lab, using 700 college students, and duplicated their initial field survey results.
Overall they discovered that a well-lit atmosphere influences diners to order 16% to 25% more healthy foods, like grilled fish, vegetables, or white meat, than people eating in dimly lit rooms. Those dining in the dark ordered 39% more calories.
"We feel more alert in brighter rooms," said lead author Dipayan Biswas in the report, "and therefore tend to make more healthful, forward-thinking decisions."
To test this theory, the team gave participants a caffeine placebo or just told them to be more alert. This caused the people in dimly lit rooms to order just as healthfully as those in bright rooms.
Like any knowledge, this kind of result could be used for good or for evil, as the study concludes:
While restaurant and perhaps grocery store managers can use these insights and their ambient light switches to nudge consumers toward targeted food choices, such as healthy or high margin signature items, health conscious consumers can opt for dining environments with bright ambient lighting.
But who wants to have dinner in a bright, aseptic room? The news isn't all bad. "Despite ordering less-healthy foods [in darker rooms]," says co-author Bill Wansink, "you actually end up eating slower, eating less, and enjoying the food more.
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