Free Radicals
Free radicals are reactive substances produced by oxidation that cause damage to the cells. They are produced continuously in the body either from normal essential metabolic processes, or from external sources such as cigarette smoke, ultraviolet light, environmental pollutants, radiation and certain drugs, pesticides and industrial solvents. Research suggests that free radicals are involved in the formation of several degenerative diseases associated with aging, including cancer, cardiovascular disease, cognitive impairment, Alzheimer’s disease, immune dysfunction, cataracts, and macular degeneration. Chemical reactivity from free radicals that are not inactivated can damage cellular molecules such as proteins, carbohydrates, lipids and nucleic acids. Antioxidants have the capability of stabilizing harmful free radicals before they can react and cause damage to cells. While the human body has several built-in defense mechanisms to protect against free radical damage, aging, poor diets, and increased amounts of oxidative stress cause these defense mechanisms to become less effective. This creates the potential for accelerated aging and reduced well-being (Lobo, et al., 2010).
Phytochemicals
Phytochemicals are biologically active compounds found in plants. While they are not classified as nutrients like vitamins and minerals, they have a major impact on our body systems, helping to increase health and prevent illness and disease. While thousands of phytochemicals have been identified by scientists, only a fraction of them have been studied closely for their role in human health. Research has shown that some phytochemicals are powerful antioxidants, immune boosters and hormone stabilizers, and thus they have been promoted to help prevent and treat many health conditions, such as cancer, diabetes, heart disease, and high blood pressure (ACS, 2013).
Super-Foods Offer Super Protection
Phytochemicals are not stored in the body, and thus it is necessary to consume phytochemical-rich foods on a regular basis. Super-foods such as Acai berry, Mangosteen, Goji berry, Pomegranate, Green tea leaf, and Grape seed and skin are especially concentrated sources of protective antioxidant phytochemicals.
Acai berry is the fruit of a palm tree native to Central and South America. When ripe, the berries are dark purple in color and about the size of a blueberry. The pulp and skin of acai are rich in anthocyanidins, proanthocyanidins, and polyphenolic compounds. Acai berry has been shown in studies to exhibit significant antioxidant capabilities (Schauss, et al., 2006). The antioxidants in acai are able to enter human cells in their fully active form where they quench free radicals. The berry also has anti-inflammatory properties, inhibiting COX-1 and COX-2 activity.
Mangosteen is a tropical plant native to Southeast Asia. Studies reveal that xanthones from the fruit hulls of mangosteen have antioxidant, antibacterial, antifungal, and anti-inflammatory properties (Pedraza-Chaverri, et al., 2008). A recent study examining the effects of a mangosteen xanthone extract on colon-cancer cells showed the extract to induce cancer cell death and inhibit further tumor growth (Aisha, et al. 2012).
Goji berries are rich in beta-carotene, zeaxanthin, polyphenols and polysaccharides. A study on cancer patients in China revealed that patients given Goji berry polysaccharides along with conventional cancer treatment had a 40.9% response rate to the treatment, while patients receiving conventional treatment without Goji berry supplementation had only a 16.1% response rate (Cao, et al., 1994). Additionally the Goji berry-supplemented patients experienced longer remissions and had a significant increase in natural killer cell activity. Another study showed that daily supplementation of Goji berry for 14 days has positive effects on mood, feelings of well-being, neurological performance and digestive function (Amagase, et al., 2008).
Pomegranate contains thousands of phytochemicals including anthocyanadins, ellagic acid, catechins, procyanidins, flavonols, fatty acids and sterols. Human studies show that pomegranate polyphenols and their metabolites are readily absorbed into tissues where they offer protection against elements of various diseases (Seeram, et al., 2006). Pomegranate increases nitric oxide production in the endothelial cells of the vascular system protecting against cardiovascular disease. Studies show consumption of the juice benefits patients with carotid artery stenosis, those with hypertension, and those with coronary heart disease (Aviram, et al., 2004). Pomegranate has also been studied in the treatment of various types of cancer. In one study when men with aggressive prostate cancer were given pomegranate juice daily after treatment by surgery or radiation, the rate of PSA rise was reduced by 50% over the course of just one year. In addition cancer cell proliferation was reduced and apoptosis was increased (Pantluck, et al., 2006). Another study examined the effects of pomegranate on colon cancer cells and found that the polyphenolic phytochemicals contained in the fruit suppressed inflammatory cell signaling proteins and inhibited colon cancer cell growth and proliferation (Adams, et al., 2006).
Green Tea leaf contains abundant amounts of a well-researched antioxidant called epigallocatechin gallate (EGCG). Peer-reviewed scientific research has consistently shown that EGCG is a potent antioxidant, deactivating free-radicals and protecting cells from oxidative damage (Khan, et al., 2006). By virtue of its antioxidant effects, EGCG has been shown to exert a number of beneficial activities, such as reducing inflammation and normalizing cell and tissue functions in the body. Epidemiological studies examining green tea intake on cardiovascular health show an association between increased green tea consumption and reduced risk of hypertension, endothelial dysfunction, and cardiac cell damage. Green tea also has positive effects on body weight, BMI, subcutaneous fat, and waist circumference (Sandhya, et al., 2013). Other studies have shown that EGCG has a benefit in normalizing blood glucose and protecting the pancreas from oxidative damage (Wolfram, 2007).
Grape skin and seed are abundant in a group of polyphenols called procyanidins. Procyanidins are strong antioxidants, lipid peroxidation inhibitors, and free radical scavengers. They have antimutagenic effects, meaning they can counteract environmental mutagens, which are thought to be one of the causes of chronic degenerative diseases. Procyanidins also increase circulation making them helpful for conditions such as venous insufficiency, a condition in which the veins have trouble sending blood from the legs back to the heart (Feringa, et al., 2011). Due to procyanidins positive effects on circulation, grape skin and seed extracts are also helpful for numerous vision disorders.
References:
Adams LS, et al. Pomegranate juice, total pomegranate elagitannins, and punicalagin suppress inflammatory cell signaling in colon cancer cells. J Agric Food Chem. 2006 Feb 8;54(3):980-5.
Amagase H, et al. A randomized, double-blind, placebo-controlled, clinical study of the general effects of a standardized Lycium barbarum (Goji) Juice, Go Chi. J Altern Comp Med. 2008 May;14(4):403-12.
Aisha AF, et al. In vitro anti-colon cancer effects of Garcinia mangostana xanthones extract. BMC Complement Altern Med. 2012. Jul 20;12:104.
American Cancer Society (2013). Phytochemicals. Retrieved November, 2013, from http://m.cancer.org/
Aviram M, et al. Pomegranate juice consumption for 3 years by patients with carotid artery stenosis reduces common carotid intima-media thickness, blood pressure and LDL oxidation. Clin Nutr. 2004 Jun;23(3):423-33.
Cao GW, et al. Observation of the effects of LAK/IL-2 therapy combining with Lycium barbarum polysaccharides in the treatment of 75 cancer patients. Zhonghua Ahong Liu Za Zhi. 1994;16:428-31.r
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Khan N, et al. Targeting Multiple Signaling Pathways by Green Tea Polyphenol EGCG. Cancer Res. 2006 March;66:2500.
Pantluck AJ, et al. Phase II study of pomegranate juice for men with rising prostate-specific antigen following surgery or radiation for prostate cancer. Clin Cancer Res. 2006 Jul 1;12(13):4018-26.
Pedraza-Chaverri J, et al. Medicinal properties of mangosteen (Garcinia mangostana). Food chem Toxicol. 2008. Oct;46(10)3227-39).
Sandhya K, et al. Polyphenols: Benefits to the Cardiovascular System in Health and in Aging. Nutrients. 2013 Oct; 5(10): 3779-3827.
Schauss AG, et al. Antioxidant capacity and other bioactivities of the freeze-dried Amazonian palm berry, Euterpe oleraceae mart. (acai). J Agric Food Chem. 2006 Nov 1;54(22):8604-10.
Seeram NP, et al. Pomegranate juice metabolites are present in human plasma and some persist in urine for up to 48 hours. J Nutr. 2006 Oct;136(10):2481-5.
Wolfram S. Effects of green tea and EGCG on cardiovascular and metabolic health. J Am Coll Nutr. 2007 Aug;26(4):373S-388S.
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