Eat Your Phytochemicals and be Healthy

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Phytochemicals are found in all plants, they protect the plants from bacteria, viruses, fungi and the ultraviolet of the sun. Phytochemicals also protect us when we eat them.

Phytochemicals are found in all plants, they protect the plants from bacteria, viruses, fungi and the ultraviolet of the sun; and they are healthy for us. More than 1,000 phytochemicals have been identified and more will be. There are 99 phytochemicals in wheat kernels alone.

The Different Types and Actions of Phytochemicals

Antioxidants: Most phytochemicals have antioxidant properties. Antioxidants protect our cells from oxidative damage. Oxidative damage to our cells is linked to many diseases including Alzheimer’s disease.

Oxidative damage is cause by too much oxygen. For example when you cut an apple and leave it out, exposing it to the oxygen in the air, it turns brown; that is oxidative damage. If you had put lemon juice on this cut-open apple, it wouldn’t have turned brown like that, because lemon is an antioxidant to the apple cells.

Oxidation sometimes produces what are known as free radicals that can cause damage to cells. When you hear of a "free radical scavenger", this means something that finds and gets rid of these free radicals. Oxidation is a normal process, so we need antioxidants to balance out this process. Free radicals can cause cancer, cardiovascular disease, macular degeneration, cataracts and Alzheimer’s disease. These phytochemicals keep us healthy from oxidation.

Healthy fruit and vegetables from farmers market. Photo by Whitney in Chicago

Flavonoids (bioflavonoids) are antioxidant phytochemicals. Some have as much as 50 times more antioxidant activity than vitamin C and E, and red grapes are more than a thousand times more powerful than vitamin E as an antioxidant. Flavonoids have been reported to have anti-viral, anti-inflammatory, anti-tumor, anti-allergic and anti-platelet benefits. Flavonoids are found in fruits, vegetables, wine, green tea, onions, apples, kale and beans. Here is a list of the more common flavonoid phytochemicals.

  • Quercetin: These phytochemicals protects the lungs from pollution and cigarette smoke, reduces inflammation from allergies and inhibits the growth of head and neck cancers. Quercitin is found in apples, pears, cherries, red wine, grapes, kale, onions, garlic, lettuce and green tea.
  • Anthocyanins: These phytochemicals protect against aging. Studies with blueberries have shown that anthocyanins might improve balance, coordination and short-term memory. Cranberries have been shown to prevent urinary tract infections. Anthocyanins are mainly found in blueberries, cranberries, cherries, strawberries, kiwi and plums.
  • Reservatrol phytochemicals could reduce the risk of cancer, heart disease, blood clots and stroke. Reservatrol has been found to reduce the growth of cancer cells and could possibly aid in changing malignant cells back to normal cells. It is found in red wine, red grapes and red grape juice.
  • Catechins are the phytochemicals that have been found to inhibit the growth of antibiotic-resistant Stapphylococcus infections. Studies have shown catechins can reduce the rate of stomach and lung cancer, prevent DNA damage, prevent gum disease and retards the onset of atherosclerosis. Studies in Japan with green tea have shown that catechins can cause people to lose body fat. Foods high in catechins are green teas, grapes, grape juice, wine and especially red wine.
  • Tangeretin may help prevent cancers of the head and neck, lowers cholesterol and has neuroprotective properties, which can help with Parkinson disease. It is found in citrus fruits and citrus juices such as lemons, limes, tangelos, grapefruit, mandarins and oranges.
  • Carotenoids are the phytochemicals that are what gives vegetables the bright red, yellow, orange and dark green colors. Carotenoids are also very powerful antioxidants and contain anti-cancer and anti-aging properties. Carotenoids also stimulate cell-to-cell communications, which is important for maintaining cells and keeping cells from turning cancerous. The carotenoids alpha and beta-carotene convert into vitamin A in the body and enhance the immune system. Large doses of vitamin A can be harmful to you, but you cannot get too many carotenoids from plant foods.
  • Alpha-carotene is more powerful than beta-carotene when it comes to inhibiting tumor growth and protects the skin, eyes, liver and lungs against cell damage. It is found in cooked carrots, carrot juice and pumpkins. This is a healthy low-sodium vegetable soup recipe.
  • Beta-carotene, like alpha-carotene, it is an antioxidant cleaning the body of the free radicals. Beta-carotene is also believed to promote a healthy reproductive system in women. A meta-analysis showed that beta-carotene could protect the skin against sunburn. It also keeps the eyes healthy, preventing night blindness and general health of the eyes. Studies [1] have shown that women with the highest blood levels of beta-carotene had an 80% reduction in cervical cancer. Foods include carrots, pumpkins, sweet potatoes, spinach, collards, kale, winter squash and cabbage.
  • Lutein is a strong antioxidant that protects the eyes against macular degeneration. It also reduces the clogging of the arteries. Foods high in Lutein include spinach, collard greens, kale, summer squash and most other greens.
  • Lycopene is the photochemical that has become commonly known for reducing the risk of prostate cancer. It has many other benefits as a powerful antioxidant, it protects against stomach, lung, colon and skin cancers. Lycopene has been found to be an antibacterial and an antifungal, reducing gum disease and Candida albicans. Lycopene helps protect against vascular disease and infections in people with diabetes. It is also an antitoxic and may protect against toxins like cadmium, aflatoxin and cyclosporine. Foods high in lycopene include anything with tomatoes. Cooking tomatoes into paste or sauce releases more lycopene. Other foods are watermelon, guava, pink grapefruit and red oranges. Here is a healthy tomato soup recipe.

Healthy phytochemicals from berries.                                 Winter squash soup and almonds. Photo: Shawn Henning

Other Phytochemicals

Indoles are phytochemicals that inactivate estrogens and stimulate the production of an enzyme that causes estrogen to be less effective reducing the risk of hormone-dependant cancer like some forms of breast cancer. Foods with these phytochemicals are the cruciferous vegetables including cabbage, radishes, broccoli, kale, Brussels sprouts, bok choy, turnips and cauliflower. These groups of phytochemicals are powerful cancer fighters.

Isoflavones are converted to plant estrogens (phytoestrogens) and may help to inhibit the growth of hormone-dependent cancers. An isoflavone from soy is genistein, which has anticancer and antioxidant properties and can only be found in soy foods such as miso, soymilk and tofu. They also help to protect us against heart disease, lower cholesterol, and to ease menopausal symptoms.

Phenolic Acids include capsaicin. This is the chili pepper family of vegetables. These can relieve symptoms of arthritis and improve flexibility. It also protects the stomach membranes and can protect against certain ulcers.

There are many other phytochemicals including alkaloids, coumestans, hydroxycinnamic acids, lignans, coumarins, curcumins, monophenols, monoterpenes, phytosterols, saponins, tritepenoids and xanthophylls that we get in all plants foods that are healthy for us.

Conclusion on Phytochemicals

Eating a variety of phytochemicals is what keeps us healthy. Phytochemicals are in all plants; in the roots, leaves, grains, grasses, spices, herbs, mushrooms, fruits and vegetables. The best way to be healthy is to eat a wide variety of edible plant foods and there are many ways to include plant foods and phytochemicals into every meal.

© 2009 Sam Montana


[1] J.A. Wylie-Rossett et al., “Influence of vitamin A on Cervical Dysplasia and Carcinoma In Situ,“ Nutrition and Cancer 6 (1984): 49-57; R.W.C. Harris et al, “Cancer of the Cervix Uteri and Vitamin A,” British Journal of Cancer 53 (1986): 653-659: K. Brock et al, “Nutrients in Diet and Plasma and Risk of In Situ Cervical Cancer, “Journal of the National Cancer Institute 80 (1988): 580-585

Linus Pauling Institute

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David Swardlick
Posted on Jul 19, 2012
Molly Buckle
Posted on Sep 4, 2009
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Sam Montana
Posted on Sep 3, 2009
carol roach
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Steve Feller
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