Susan Bowerman, MS, RD, CSSD
Nature's rainbow - in the form of colorful fruits and vegetables - provides more than just a feast for the eyes. Many of the pigments that give fruits and vegetables their wonderful colors provide unique nutritional benefits, too.We are often tempted to associate foods with a single nutrient or condition. We might eat oranges for vitamin C, or carrots because their vitamin A helps promote healthy eyesight.
But beyond these individual vitamins and minerals, fruits and vegetables contain literally thousands of phytochemicals - naturally occurring plant compounds that have far-reaching benefits to our health.Phytochemicals act as antioxidants, which defend against damage that can occur to cells and tissues as a result of normal, everyday metabolism. And, they help keep inflammatory processes in check, which reduces the risk of the development of certain conditions such as diabetes or heart disease.
Although some phytochemicals are colorless, many of them provide fruits and vegetables with their beautiful colors. The most widespread group of phytochemicals in nature are the carotenoids - pigments such as lycopene that gives tomatoes their red color, beta-carotene that gives carrots get their orange hue, and yellow-green lutein that tints foods like spinach, avocado and romaine lettuce.
And, each fruit and vegetable has its own unique phytochemical profile and level of antioxidant activity which is why health authorities recommend not only an abundance of fruits and vegetables in the diet, but a wide variety, too - deep red blood oranges provide different phytochemicals and pigments than their bright orange relatives.
But it may not be enough to just simply eat whole fruits and vegetables. Research is telling us that combining these foods may be more beneficial than eating them alone.
It appears that the effects of phytochemicals are enhanced when they are combined - they work together so that the sum of their benefits is greater than the individual parts. For example, it has been shown that the antioxidant effects of a combination of red apples, blueberries, grapes and oranges are much larger than when any of the fruits are taken individually.
Other compounds that naturally occur in whole foods come into play, too. The classic guacamole and salsa combo has a lot going for it - the healthy fat in the avocado helps the body to better absorb not only the lutein in the avocado, but also the lycopene from the tomato. So eating these two together may pack a better antioxidant punch than eating either one by itself.
Chopping, grinding and cooking carotenoid-rich foods helps to release these powerful substances from the cell walls of the plant, too, making them up to six times more available to the body than when the foods are eaten fresh. Raw foods are fine - but mix it up. Rather than always taking your lycopene-rich tomatoes raw in a salad, have some tomato juice, soup or pasta sauce on the menu from time to time.
Cooked or raw, no one can deny that increasing your fruit and vegetable servings is a great first step toward reaping the benefits of the phytochemicals they contain. But adding new foods, new varieties and new combinations may be even better.
