There’s a reason why most fast food joints end up with similar hues for their logos and interiors. The colors orange, red, and yellow act as appetite stimulants by increasing your mental activity and making you feel hungrier. According to The Psychology of Color, red evokes strong emotions and appetite, while orange stimulates excitement, conversation, and cravings. As for yellow, it’s considered the cheeriest color, so being in happy surroundings can increase a person’s appetite.
Popular fast food brands that use red in their logos include McDonald’s, Jollibee, KFC, Pizza Hut, Chowking, and Wendy’s, while restos that prefer orange interiors include Pancake House and Jamba Juice. Also, note that many healthy fruits and veggies are orange, red, or yellow, such as squash, carrots, pumpkins, bananas, apples, strawberries, and cherries.
On the opposite end of the color spectrum are the least appetizing colors—gray, black, and blue. While they work well in architectural and artistic aspects, such as blue bedrooms to bring calmness and peace, these colors aren’t appealing to eat. Have you noticed that there are few naturally occurring foods that are gray, black, or blue? If you’re looking for a trick to suppress your appetite, try eating in a room with black, blue, or gray walls. Even a blue light in the kitchen can curb your desire to devour a feast [via All Women’s Talk].
Note that not all colors have the same effects on each person. In the end, it all depends on your psychological association with the specific color. There are hues that evoke different feelings, memories, and instincts in different people.