Phytonutrients,” “phytochemicals” and “antioxidants” have become the bigbuzzwords in the ongoing search for better health and longer life in recent years—we see these terms in advertising and news articles and hear them from the popular health gurus, but what does all the hype mean in real terms?
Phytochemical and phytonutrient are both broad terms that describe a variety of nutrients that occur naturally in plant foods. These foods are loaded with the basic nutrients that we all learned about back in school—vitamins, minerals, fiber, protein and such—but they are also packed with a huge array of other compounds that protect and enhance health. Researchers have identified hundreds of phytonutrient components, but are only beginning to unlock all their secrets.
Phytonutrients have many different roles; some reduce the risk of various types of cancer, some are important for good cardiovascular health, some enhance brain function and others may strengthen the immune response, regulate hormones or just work to keep us generally healthy.
We all recognize phytonutrients, we just might not know it—carotenoids and flavonoids add color to foods; terpenoids and sulfur compounds are responsible for the characteristic scents; terpenoids and tannins contribute flavors. These sensory components help us know whether a fruit or vegetable is ripe or spoiled, and to some extent whether it is raw or cooked. The scents of cinnamon and ginger are clues to the warming tendencies of these spices, while the pale hues of cucumbers and melons evoke expectations of moisture and coolness. The rainbow colors of fruits and vegetables attract our attention and beg us to touch and arrange produce into beautiful salads or artful displays.
Some of the best-known phytonutrients belong to a class known as antioxidants. This is a powerhouse group that works to neutralize free radicals in our bodies. When our cells burn fuel to produce energy, oxygen is also burned as part of the process. This oxygen, along with environmental pollutants, tobacco smoke, radiation and ultraviolet light, create unstable free radicals. Free radicals can damage or destroy cells and tissue or cause cellular mutations and these negative changes result in the formation of more free radicals. The cycle keeps repeating in the same way that browning spreads across the cut surface of an apple or pear. Antioxidants help reduce and repair the damage of free radicals, keeping our immune systems and our DNA strong and healthy.
The earliest recognized antioxidants were probably vitamins C and E. Hippocrates was the first person to describe the nutrient-deficiency disease we know as scurvy. By the mid-eighteenth century sailors were aware of the need to stock fresh fruits and vegetables on their ships to prevent scurvy from decimating the crews, even if they had never heard of vitamin C or antioxidants. Citrus fruits were a popular choice when available, and ships sailing from northern countries would often carry barrels of sauerkraut in their provisions. The reduction of scurvy among crews eating fresh produce was so great that many routes were planned to take advantage of ports where fresh fruits and vegetables could be replenished. In 1860 the Royal Navy commanded that all of its sailors and officers would receive daily doses of lime juice from British plantations in the Caribbean to prevent scurvy.
In more recent times, Linus Pauling championed the ability of vitamin C to help prevent illness and aging. He also did extensive research on the use of mega-doses of intravenous vitamin C to treat cancer. His work was controversial with mainstream medical practitioners and researchers, but did much to open the public’s eyes to the potential benefits of supplement use. In 2007 Canadian researchers presented new evidence supporting Pauling’s findings for vitamin C’s role in cancer therapy.
In addition to its rolein supporting the immune system, vitamin C is vital for forming collagen. Collagen makes up the connective tissues that literally hold our bodies together and give us shape. Collagen is part of the wound-healing process and aids in hormone and neurotransmitter production.
The human body, like those of other primates, does not have the ability to make vitamin C as many other animals do, so it must be included in our daily diet. Vegetables and fruits, especially citrus fruit, are rich sources of this vitamin. In addition to citrus kiwi, tropical fruits, berries, red and green peppers, broccoli, cabbage, leafy greens and tomatoes are good choices for vitamin C. It is important to include raw vegetables and fruit in the diet because vitamin C can be easily destroyed during the cooking process.
Vitamin E has been included in skin care products for many years to reduce or eliminate stretch marks, scars, wrinkles and age spots. Whether it will truly make you look younger or not, topical applications of vitamin E do help protect skin from free radical damage caused by ultraviolet light, pollutants and smoking. In fact, vitamin E is sucha powerful antioxidant that it is often included in fish oil supplements, packaged foods and vegetable oils to prevent them from becoming rancid. When vitamin E is included in sunscreens it helps to prevent skin cancer; other vitamin E preparations help heal eczema and psoriasis. Vitamin E is important for good cardiovascular health and may be useful in preventing Alzheimer’s disease and relieving inflammatory conditions.
Vitamin E is made up of tocopherols and tocotrienols; if you read the label on a bottle of supplements it will usually state “mixed tocopherols” or “d-alpha tocopherols,” but some research indicates that tocotrienols might be the more important part of this antioxidant. Tocopherols occur naturally in corn, soybeans and olive oil, while tocotrienols are found in rice bran, palm and barley oils. Many other whole grains, nuts, and seeds contain good amounts of vitamin E. Pecans are especially high in gamma tocopherols, which help to increase levels of “good” cholesterol and reduce the “bad.” Eggs, organ meats and cold-pressed vegetable oils are other good sources of vitamin E.
Our bodies normally produce the antioxidant coenzyme Q10. It is needed for energy production and is found in greatest concentrations in the organs that have the most energy use, notably the heart. Research has shown that CoQ10 supplements can be helpful in treating a variety of cardiovascular problems; it is also known that statin medications reduce the body’s ability to manufacture CoQ10 and many health experts now recommend taking CoQ10 supplements if you take a statin. A few studies have also shown that CoQ10 can be beneficial to migraine sufferers. Research is underway to study this nutrient’s effect on diabetes and cancer. CoQ10 occurs naturally in oily fish and organ meats as well as nuts and sesame seeds.
Carotenoids are one of the most familiar groups of antioxidants. These are the substances that add green, red, yellow and orange pigments to food. Some of the best known include beta-carotene, lycopene, zeaxanthin and lutein.
The liver uses beta-carotene to make vitamin A, which is important for supporting the immune system and for the health and maintenance of mucous membranes. This nutrient is abundant in sweet potatoes, winter squash, carrots, peppers and romaine lettuce. Guava and papaya are good fruit sources of vitamin A.
Lycopene is a potent cancer-fighting carotenoid, being especially important for the prevention of the growth of abnormal cells. It seems to be particularly useful for the prevention of prostate cancer in men. It also protects against stomach and lung cancer and inhibits the growth of breast tumors. Research has shown that people with high blood levels of lycopene are about one-third less likely to develop heart disease than those with low levels. Think red when you are searching for lycopene—it is responsible for those rich red pigments in vegetables and fruits. Tomatoes are a good source of lycopene, especially when cooked and eaten with a bit of oil, so ask for extra sauce on your pizza and enjoy pasta or vegetables with marinara sauce, or enchiladas baked in ranchero sauce. Lycopene is also found in watermelon and pink grapefruit, but guava is the lycopene superstar in the fruit world.
Lutein is a carotenoid that is beneficial to the eyes. It protects against age-related macular degeneration. According to the National Eye Institute, age-related macular degeneration is one of the leading causes of vision loss in people over 60. Lutein was also found to help prevent colon cancer in a study conducted at the University of Utah Medical School. Dark leafy greens are the best sources of lutein, especially spinach. It is also found in cruciferous vegetables like broccoli, kale and Brussels sprouts and in legumes and egg yolks.
Zeaxanthin often occurs together with lutein and is also valuable against age-related macular degeneration. Zeaxanthin and lutein are the only carotenoids that research has identified in the macula. It is interesting to note that Mother Nature has coupled these nutrients in many food sources including dark leafy greens, corn and kale. Zeaxanthin also helps strengthen the immune system and fights free radicals throughout the body.
Flavonoids are another familiar group of antioxidants. Scientists have identified over 4,000 of these plant-based nutrients. Flavonoids perform many different functions in the body including immune system support, toxin removal, support of the cardiovascular system, and risk reduction for estrogen-related cancer. Flavonoids also enhance the workings of vitamin C.
Anthocyanins are flavonoids that show up in purple-red pigmented foods. They may be the most powerful flavonoids studied so far. Anthocyanins guard against free radical damage; they help build collagen and reduce the risk of age-related macular degeneration. Blueberries are one of the best sources of anthocyanins, but they are also abundant in cranberries, bilberries and other berries. Anthocyanins can be found in eggplant, tomatoes and red grapes and in cherries, beets, and pomegranates—virtually all vibrantly colored fruits and vegetables contain anthocyanins. Acai berries seem to be one of the best sources of anthocyanins known so far, but they grow only in the Amazon rainforest and are very perishable. They have only recently become sensationally popular; how this berry’s new status will affect the indigenous peoples of the Amazon and the health of the rainforest remains to be seen.
Catechins are flavonoids that are abundant in white and green tea, cocoa and some chocolate, wine and grape juice, and are somewhat less available in black, white and oolong tea. Catechins help to reduce plaque buildup in the arteries and laboratory tests indicate that they may reduce the growth of cancerous cells. Some researchers believe that consuming catechins may help slow the aging process; others call this an “essential” nutrient—there has even been a move to have catechins reclassified as a vitamin group.
Sulphoraphane, a phytonutrient found in broccoli and other cruciferous vegetables, made headlines several years ago when it was found to have a strong impact on cancerous cells. A study at Johns Hopkins University School of Medicine in Baltimore, MD identified broccoli sprouts as containing the highest concentrations of sulphoraphane and showed that they were very effective at stopping the growth of Helicobacter pylori, which is a bacterium responsible for the stomach inflammation leading to ulcers. A new study out of UCLA shows that sulphoraphanes can reduce respiratory inflammation that can cause asthma and chronic obstructive pulmonary disease.
Phytoestrogens are a class of nutrients that are protective against estrogen-related cancers. The most highly publicized-and most controversial—are the phytoestrogens found in soybeans and products made from them; they are also known as isoflavones. Many experts believe that isoflavones can help balance female hormones, relieve menopausal symptoms, protect from heart disease and prevent estrogen-related cancers of the breast, prostate and colon in men and women. Other experts caution against high-dose isoflavone supplements and processed foods created from soybeans, saying that over-consumption of soy can be the cause of a variety of health problems ranging from allergies to thyroid disease and cancer. Most agree that women with breast cancer should be cautious; genistein is a component of soy isoflavones that seems to accelerate the growth of breast cancer cells in laboratory tests.
Lignans are food components that are converted into active phytoestrogens by bacteria in our digestive tracts. In recent years ground flaxseed has become a popular source of this nutrient, but lignans are available in a variety of foods including whole grains, fruits and vegetables. Flaxseed has the additional benefit of supplying alpha-linolenic acid, a good vegetarian source of Omega-3 fatty acids. Studies show that women who consume more lignans have lower rates of breast cancer; phytoestrogens from lignans have been shown to reduce hot flashes in menopausal women and help to balance hormones during perimenopause. Lignan consumption has also been linked to better cardiovascular health and reduced risk of insulin resistance. Whole flaxseed remains mostly intact when it passes through the body, but a small coffee grinder turns the seeds into meal quickly. The oils in flaxseed are unstable; to prevent rancidity grind the seeds in small quantities and store ground flaxseed, tightly sealed, in the refrigerator. If you buy pre-ground seeds, choose a brand that is vacuum-sealed, store it as noted above and use it quickly.
Allicin is a powerful compound found in garlic, and in lesser amounts in onions and other members of the Allium plant family. In the past decade, studies have confirmed that allicin seems to be beneficial for reducing cholesterol levels, blood pressure and atherosclerosis. Garlic—and the allicin it contains—has been a folk remedy for all kinds of viral and bacterial illness for centuries and modern research indicates that allicin does have significant anti-inflammatory and antibacterial properties. As with other phytonutrients, allicin seems to be most effective when consumed as a food, rather than a supplement. To get the most benefit, chop raw garlic and let it rest for ten minutes or so before using it.
There are thousands of other phytonutrients in food and the study of them will go on as long as benefits are uncovered. With each new health discovery you can expect to see more processed foods enhanced by the addition of the “super food” of the moment—over 300 antioxidant-enhanced products hit U.S. stores last year—but most experts recommend that we get our phytonutrients from whole foods. In many studies, supplementing with phytonutrients has not produced the same results as dietary intake, and“functional foods”—those with phytonutrients added—often do not contain enough of a compound to provide any measurable benefit. In many cases, the natural components in food work together, or may even be dependent on each other, to provide nutritional benefits. The best way to get the health benefits of phytonutrients is to eat an assortment of fruits, vegetables, nuts and seeds every day. Eat foods of various colors, but try to include dark leafy greens and orange vegetables daily and vary the foods you choose regularly. Many health experts now suggest that we should fill half of our plate with vegetables and divide the remaining space evenly between a whole grain and a lean protein source; others recommend eating at least four cups of vegetables daily or two vegetable servings at each meal including breakfast.
The best fresh produce around can be found here at the Co-op, thanks to our picky Produce staff—the buyers are always on the lookout for newly available fruits and veggies at the most reasonable price, the Produce receivers make sure that we have top-quality choices for you and the stockers get it out on the sales floor in all its glory. The whole team works quickly so you can get the maximum benefit from those fruits and vegetables. The Produce staff is always happy to answer any questions you might have about ripeness or preparation, too. Stop in the Bulk aisle to stock up on fresh nuts, seeds and grains to complement your produce choices. The Bulk aisle is the place to find herbs and spices loaded with phytonutrients too; more herbs and a wide variety of teas can be found in the Health and Wellness department. And, as the ad slogans say, remember to “eat a rainbow everyday!”