Phytonutrients (aka, phytochemicals) are substances that plants produce to guard their integrity, such as protection against ultraviolet radiation or destruction from insects. Researchers estimate there are more than 25,000 different phytonutrients, which makes it a bit challenging to identify which ones you should be sure to focus on in your diet.
Phytonutrients are highly desirable for humans as well because of their antioxidant and anti-inflammatory powers and their ability to enhance immune function, eliminate carcinogens, and repair DNA that has been damaged by toxins. In fact, the US Department of Agriculture has stated that following a diet that is rich in phytonutrients can be effective in lowering your risk of heart disease and cancer.
Yet at the same time, it is also difficult to pinpoint the exact health benefits you can get from specific phytonutrients because of the complexity of each plant’s biological makeup and active compounds. According to Louis Premkumar, a professor of pharmacology at Southern Illinois University School of Medicine, “The levels of active ingredients [in each plant] can vary, depending upon where the plant is grown, the amount of fertilizers used, whether they are cooked on uncooked, and so on.”
We want to make the task of identifying important phytonutrients easier by introducing you to six candidates—some groups and some individual– you should include in your diet. Although all phytonutrients are found in plant foods, there are specific fruits, vegetables, nuts, grains, and seeds that are especially rich in certain phytochemicals, so be sure to vary your diet as much as possible.
Lignans. These phytonutrients are in a class known as phytoestrogens, which means they mimic the effects of estrogen. Lignans are present in excellent levels in flaxseeds and in high levels in apricots, broccoli, kale, oat bran, poppy seeds, rye, sesame seeds, and strawberries. Lignans reportedly can help prevent hormone-related cancers, such as ovarian, breast, and endometrial.
Resveratrol. This stilbenoid phytonutrient is typically associated with red wine and red grapes, although it is also found in blueberries, coca, cranberries, and peanuts. Resveratrol has been studied for its heart-healthy traits as well as helping with aging, diabetes, and cognitive decline. Some research has shown, for example, that resveratrol may improve insulin sensitivity and glucose tolerance and improve blood flow to the brain.
Carotenoids. This is a huge family—more than 600 members in all. That’s because they include the pigments that colour plants, including red, yellow, and orange. You probably recognize some of the more common carotenoids, such as lycopene, beta- carotene, lutein, and alpha-carotene.
The more brightly coloured the fruit or vegetable, the more potent the carotenoid. Generally, these potent antioxidants support and promote immune system activity, help reduce cancer and cardiovascular disease risk, benefit vision, and facilitate communication between your body’s cells. Some of the foods richest in carotenoids include carrots, bell peppers, citrus, kale, mangos, papaya, sweet potatoes, tomatoes, and yams.
Ellagic acid. Ellagic acid is present in plants as ellagitannin, which is a combination of ellagic acid and glucose. Foods rich in ellagic acid include blackberries, cranberries, grapes, pecans, pomegranates, raspberries, strawberries, and walnuts.
The ellagic acid in all of these delicious foods may help eliminate carcinogens from the body, lower blood pressure, and improve glucose metabolism. Some research also suggests ellagic may assist in fighting cancer by changing the structure of tumour cells.
Flavonoids. The large group of flavonoids includes numerous subgroups, such as anthocyanins, isoflavones, flavones, and flavonols. Overall, flavonoids are associated with protection against cardiovascular disease, cancer, and aging. Some of the more well-recognized members of this group are kaempferol and quercetin, the latter of which is found in red wine.
In a large, 25-year study of flavonoids (the Seven Countries Study), researchers found that eating foods with flavonoids was significant associated with longer life. Some of the best sources of flavonoids include apples, berries, broccoli, buckwheat, cabbage, carrots, dark chocolate, coffee, grapefruit, kale, leeks, parsley, red wine, and tomatoes, among others.
Written by Deborah Mitchell. Deborah Mitchell is passionate about personal health and the well-being of animals and the planet. She has authored, coauthored, and ghostwritten more than 40 books, contributes regularly to several websites, and shares information on physical, emotional, and spiritual health on her blog, deborahmitchellbooks.com.
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