Variety in color stimulates our appetites. The more colors thrown together, the more we eat.
It's true. In a study, people who encountered a bowl of six colored flavors of jellybeans mixed together ate nearly 70% more than people who encountered the same six colored flavors of jellybeans in separate bowls.
In another experiment, subjects given M&Ms in ten colors ate 43% more than those given the same number of pieces, but in seven colors. The different colored M&Ms all taste the same though. Their variety is merely visual.
Color variety also plays an important role in nutrition. The health benefits of various fruits and vegetables are largely related to their color.
For example, blue and purple fruits contain a lot of antioxidants while red fruits and vegetables are high in vitamin C. You might keep unhealthful foods organized into separate compartments so they're less tempting, but mix up healthful foods like fruits and vegetables in order to stimulate appetite. When it comes to fruits and vegetables, the more colorful your plate, the better!