A study found that diners seated in darker rooms ordered dishes with 39 percent more calories on average.
Bight Lights Healthy Choices
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It turns out the dim lighting on your dinner date can affect more than the mood. New data published in the Journal of Marketing Research shows that patrons dining in well-lit spaces are 16-24 percent more likely to order healthy dishes than those in dimly lit rooms, due to a higher level of alertness.

According to the Cornell University Food and Brand Lab, researchers at the University of South Florida surveyed 160 patrons at four chain restaurants. Some diners were seated in brighter rooms, while the others ate in more dimly-lit spaces. Those who were seated in the darker rooms ordered dishes with 39 percent more calories on average and leaned towards less-healthy items, like fried food and dessert. On the other hand, those in the well-lit room skewed towards the healthier menu items like vegetables, white meat poultry, baked and grilled fish, and vegetables. A replication of the study with 700 college-aged students found the same results.

"We feel more alert in brighter rooms and therefore tend to make more healthful, forward-thinking decisions," explains lead author Dipayan Biswas. The team's flolow-up studies on diner alertness showed that when consumers in the dimly-lit rooms were given a caffeine placebo or prompted to be more alert, they made comparably healthy choices to those in the well-lit rooms, concluding that alertness is the main factor in the whether or not diners make more righteous decisions while eating out.

Before you decide to avoid low light altogether, know that Brian Wansink, study co-author and Director of the Cornell Food and Brand Lab, says "dim lighting isn't all bad... despite ordering less-healty foods, you actually end up eating slower, eating less, and enjoying the food more."

So, the next time you're faced with a case of "dining-in-the-dark," as Wansink calls it, your best defense against overindulgence could be taking a moment to be conscious and alert about what you're putting into your body. No mood-killing bright lights required.