Using a red plate or red-trimmed glass may cut the number of calories you take in -- without you even realizing it, a new study reports.
People snacked less when food was put on a red plate, and they drank smaller amounts of sweetened beverages from a cup with a red sticker on it, Swiss researchers found.
Red appears to act as a subtle stop sign in the mind, working at a level below conscious awareness.
"We believe that color is an important factor to consider when aiming to reduce consumption of unhealthy food and beverages," say the study co-authors Oliver Genschow and Leonie Reutner. Both of them are doctoral students in psychology at the University of Basel in Basel, Switzerland.
Other research has shown that factors, such as portion size, food package size and the presence of other people can all influence the amount of food or drink a person takes in.
"Our results demonstrate that the color red is such a factor," Genschow and Reutner say. "The presence of the color red reduces snack food and soft drink intake."
In the study, published online in the journal Appetite, the researchers looked at how much soft drink 41 male students consumed from a cup with a red sticker on it compared to a blue one.
Regardless of whether they liked the taste or not, guys drank more of three different flavors of iced teas from a cup with a blue sticker on it.
In a second experiment, researchers placed 10 pretzels on a red, blue, or white plate. They asked 109 men and women to complete a psychology survey, and told them they could snack on the pretzels while doing it.
People ate the most pretzels off a blue plate, the second most from a white one, and the least off a red plate. No differences in hunger levels were found among the volunteers.
Presenting the color red on plates and cups appeared to help curb food and drink intake. Researchers suggest that red plates and cups motivate people to avoid food because it's a subtle cue we connect with stopping or danger.
It's unclear whether the use of the color red in the ambiance of a restaurant, for example, would have a similar influence on diners' appetites. And scientists did not explore if their findings apply to red- or blue-tinged food, such as berries, where color is more strongly tied to a food's taste.
While this study looked at salty snacks and sweetened drinks, future research could examine whether red plates or cups may also reduce consumption of healthier foods where avoidance isn't necessary.
For now, red dishes seem to make a dent in mindless munching. "We think color may be most helpful for eating or drinking behavior that happens almost automatically, like snacking in front of the TV," say Genschow and Reutner.
When you want to reduce food intake, "it may help to keep the color red close by," the researchers suggest. So try your own experiment with a red plate, red napkin, or a red placemat to see if it affects your weight over time -- along with eating healthy and exercising more.
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