Blue/purple
Dark-colored fruits and vegetables are good sources of anthocyanins, the purplish phytonutrient that put blueberries on the map as a superfood. Other blue and purple foods offer similar benefits.
Yellow/orange
You'll find ample amounts of antioxidants, such as vitamin C and beta carotene (vitamin A)fruits and vegetables.
Red
The darker and richer the tones, the more phytonutrients you'll get in return.
Green
Dark, leafy greens such as spinach and kale are richer in nutrients.
These are just a few examples but it makes it easier for parents to learn about healthier choices. Once the parents start the change, it makes it easier to pass on the children, AND to the parents with picky eaters, it would be a different approach on how to make them eat healthier.