Phytonutrients are nutrients concentrated in the skins of many vegetables and fruits, and are responsible for their color, hue, scent, and flavor . To a lesser extent, they are also found in grains and seeds. Examples of foods rich in these nutrients include: tomatoes, red onions, green tea, grapes, red cabbage, broccoli, parsley, spinach, raspberry, blackberry, garlic, and the list goes on.
Phytonutrients ("phyto" means plant) are biologically active compounds in plants.
They work to benefit our health and longevity. Dietitians and nutritionists are clear that eating a balanced diet rich in plant foods will help reduce the risk of long-term diseases such as heart disease, stroke, cancer, and cataracts.
Phytochemical is a more recent evolution of the term that emphasizes the plant source of most of these protective, disease-preventing compounds. A true nutritional role for phytochemicals is becoming more probable every day as research uncovers more of their remarkable benefits. In fact, the term phytonutrient better describes the compounds' "quasi-nutrient" status. Someday, phytochemicals may indeed be classified as essential nutrients.
Phytonutrients are different from these more familiar food components and are not technically not "nutrients." Instead, they are classified as "non-nutient" compounds - only because there is no clear in-the-lab evidence they're "essential to life."
In the last few years, phytonutrients have been getting greater attention, as more and more research uncovers just how powerful these nutrients are for our health. They are potent antioxidants that can neutralize free radical damage. Free radicals are highly reactive chemical substances that, if left unchecked, can lead to premature aging and disease.
Unlike vitamins and minerals, phytonutrients do not have any RDA (Recommended Daily Allowance) set. However, people should avoid those foods and phytonutrient supplements to which they have a known allergy.