A Daily Dose of Color for Good Health

Color Counts When it Comes to Produce

When the current Dietary Guidelines for Americans were released in 2005, the recommendation for daily fruit and vegetable consumption was increased from 5-9 to 5-13 servings per day for adults. Despite the known health benefits of eating enough fruits and vegetables, many of us find it hard to meet these recommended intakes.

While eating a wide variety of produce is a worthwhile goal, eating a variety of different colors of fruits and vegetables is a new way of thinking about meeting that goal. Color can be just as important – maybe even more so – than quantity when it comes to fruits and veggies. That’s because colorful produce contains phytonutrients – unique plant-derived nutrients that contribute to good health.

Phytonutrient Gap

About 80% of Americans fail to eat a diet rich in specific colorful fruits and veggies according to a new study entitled America’s Phytonutrient Report. While scientists continue to identify plant-based nutrients, this report focused on 14 select phytonutrients that were grouped into color categories.

The five color categories included:

• Yellow/orange (carotenoids such as alpha-carotene, beta-carotene, beta-cryptoxanthin and lutein/zeaxanthin, as well as hesperidin);
• Blue/purple (flavonoids such as anthocyanidins and trans-resveratrol);
• White (compounds such as allicin from garlic and quercetin plentiful in onions);
• Green (lutein/zeaxanthin, EGCG, isothiocyanate and isoflavones);
• Red (phenolics such as ellagic acid and lycopene).

Using data from the National Health and Nutrition Examination Surveys, the US Department of Agriculture and other published surveys, the authors calculated the phytonutrient gap by comparing intakes of the 14 phytonutrients among the sub-group of Americans who do meet the daily fruit and veggie recommendations with intakes of average Americans. Based on this analysis, Americans are falling short in virtually every color category of phytonutrients:

• 69% fall short in green
• 78% fall short in red
• 86% fall short in white
• 88% fall short in purple/blue
• 79% fall short in yellow/orange

Phytonutrient Index Could Prove Helpful

Researchers from the University of Florida developed a phytonutrient index that ranks the amount of calories consumed from plant-based foods with overall daily calorie intake. In their study, they broke young adult volunteers into normal weight and overweight/obese groups and calculated their “index”. Normal weight adults had a higher phytonutrient index (23.5), almost twice that of the overweight group (13.2).

Although both groups ate about the same amount of calories, the overweight and obese adults consumed fewer plant based foods and therefore less protective trace minerals and phytonutrients – and more saturated fats. The overweight group also had higher levels of oxidative stress and inflammation. According to the researchers, the phytonutrient index could prove to be a useful tool to optimize diets for disease prevention.

Sample the Spectrum

To help you choose richer and more vibrantly colored foods whenever possible, here are just a few examples of foods from different color categories:

• Yellow/Orange: Butternut squash, cantaloupe, carrots, lemons, mangoes, oranges, papayas, peaches and sweet corn;
• Blue/Purple: Blackberries, bilberries, blueberries, eggplant, figs, plums, prunes, purple grapes and raisins;
• White: Bananas, cauliflower, garlic, ginger, jicama, mushrooms, onions, parsnips, potatoes and turnips.
• Green: Asparagus, broccoli, Brussels sprouts, green beans, green apples, kale, kiwi, green pepper soy and spinach;
• Red: Cherries, cranberries, pink grapefruit, pomegranates, raspberries, red grapes, strawberries, tomatoes and watermelon.

Reference:
Vincent HK, et al. Relationship of the dietary phytochemical index to weight gain, oxidative stress, and inflammation in overweight young adults. J of Human Nutr Dietetics [Epub ahead of print, September, 2009]