As you’ve probably heard before, Oxidative damage is one of the causes of aging. The color pigments in plant foods are natural Antioxidants that help slow the rate of oxidative damage and thereby preserve the length of your Telomeres.
Eating one or two pigments of color is not nearly as powerful as eating all of them, so stack the odds in your favor and go for the full gamut.
An article on the benefits of each color:
TIP: The anti-oxidants in many fibrous vegetables is not well absorbed unless they are cooked or blended. Also, according to the Linus Pauling Institute, Carotenoids (such as Lutein, Zeaxanthin, Lycopene, and Astaxanthin) require the presence of fat in the same meal for absorption. People on non-fat diets will not absorb much of these antioxidants. So make sure you eat some healthy fats with your meals such as extra-virgin olive oil, nuts, seeds, avocados, coconuts, or unpasteurized grass-fed butter.