Although pomegranates have been cultivated for thousands of years, the health-promoting properties of this "superfruit‖ have only recently come to the attention of the American public. Recent published research has focused on pomegranate’s ability to enhance the immune system and its potential benefits for helping prevent and treat cardiovascular disease, diabetes, and various forms of cancer.[1] Natural compounds in pomegranates may even thwart osteoarthritis, according to new findings published in The Journal of Nutrition.[2]
Pomegranates grow on shrubs or small trees, and are believed to be native to the Middle East and India. The reddish-colored pomegranate fruit is one of the seven food staples of the land of Israel mentioned in the Old Testament.
Endorsed by Nutritional Experts As Miami cardiologist Dr. Arthur Agatston, creator of the South Beach diet, explains, ―There’s a lot of science behind [pomegranate's] health benefits.‖ Dr. Agatston is said to recommend pomegranate to all of his patients.[3]
World-renowned nutritional expert Steven Pratt, M.D., senior staff ophthalmologist at the Scripps Memorial Hospital in La Jolla, California, counts pomegranates among the ―superfoods‖ for optimizing health.[4]
Navindra Seeram, Ph.D., points out that among exotic fruits, pomegranate’s health benefits are supported by an explosion of peer-reviewed research.[5] Dr. Seeram is assistant director of the UCLA Center for Human Nutrition and editor of a new book entitled Pomegranates: Ancient Roots to Modern Medicine. According to Dr. Seeram’s co-editor, Dr. Risa Schulman, ―the pomegranate is truly a twenty-firstcentury natural medicine.‖[6] Furthermore, pomegranate’s safety has been confirmed in a number of experiments.[6,7]
Unique Active Compounds The health benefits of pomegranate are attributed to the high levels and diversity of the fruit’s unique phytochemicals. Of these natural protective ingredients, punicalagins have been established as the chemical marker compounds that should be used for the authentication, quality control and standardization of pomegranate products.[5]
Commercial pomegranate juice has been shown to have a higher antioxidant activity than tea (Camellia sinensis), red wine (Vitis vinifera), and other fruit juices. Unfortunately, the antioxidant content of pomegranate juice can vary widely due to processing and storage techniques. Another possible drawback to using pomegranate juice, for some consumers, is its high sugar and caloric content.[8,9]
Thankfully, the recent development of proprietary extraction methods now makes it possible to consistently obtain the benefits of the whole pomegranate fruit, without the sugar and calories. This clinically-tested, natural-spectrum pomegranate whole fruit extract is standardized for both punicalagins and total polyphenol content.[8] In addition to ensuring the content and ratio of active constituents, the development of this special, natural-spectrum extract offers consumers the advantages of convenience and economy.
The High Costs of Cardiovascular Disease Cardiovascular diseases such as heart attack and stroke are among the top causes of death in the industrialized world.[10,11] Not everyone who suffers a heart attack or stroke will die. The World Health Organization estimates that worldwide, at least 20 million people survive heart attacks and strokes every year, thus requiring medical care that is very costly. Stroke, in fact, is the leading cause of serious long-term disability.
Pomegranates May Help Shield Against Stroke Damage For those who suffer from stroke-induced brain injury, few treatment options are available. A large portion of stroke research must be conducted on animals, because stroke events cannot be mimicked satisfactorily in test tube experiments. Stroke is typically associated with hypoxia-ischemia damage to the brain. Ischemia refers to blood flow to cells and organs that is not sufficient to maintain their normal function, whereas hypoxia means ―deficient in oxygen.‖ The structure within the brain called the ―hippocampus,‖ important for learning and memory, is especially vulnerable to brain cell death caused by lack of blood flow to the brain.
A recent study using animal models found a dramatic reduction in hypoxia-ischemia damage to the hippocampus (33 to 93%) when rodents drank pomegranate polyphenols. The longer the feeding period and the higher the dose of ingested polyphenols from pomegranate, the more profound the neuroprotective effects. Animals whose diet had been supplemented for two weeks with the highest dose of pomegranate polyphenols had 68% fewer cells damaged than in the brains of control animals.[6]
This study also found the brain-protective effect seen with pomegranate polyphenols to be far more significant than that of blueberries. The maximum brain-protective effect seen with blueberries was a 57% reduction of hypoxia-ischemia damage, whereas pomegranates reduced damage by as much as 93%. A small body of evidence suggests that continuing a diet of pomegranate polyphenols after a stroke is also beneficial.[6]
A Safeguard Against Cardiovascular Diseases Atherosclerosis comes from the Greek words athero (meaning gruel or paste) and sclerosis (hardness). It’s the name of the process in which deposits of fatty substances, oxidized LDL cholesterol, cellular waste products, calcium and other substances build up in the inner lining of an artery. This buildup is called ―plaque.‖[12]
Immune cells called macrophages engulf and ingest damaged, oxidized LDL particles in large numbers leading to the formation of ―foam cells,‖ a key event in atherosclerotic lesion development.[13,14] Oxidized LDL cholesterol is thought to play a key role in the inflammatory response in the arterial vessel wall.[15] Polyphenolic antioxidants, such as those found in pomegranate, are associated with the inhibition of LDL oxidation and and macrophage foam cell formation. A recent study reported on the long-term effects of pomegranate juice consumption on men and women with ―severe atherosclerosis‖ (defined as 70-90 percent narrowing of the internal carotid arteries). The carotid arteries are the main arteries in the neck that supply blood to the brain. Carotid artery disease is a major risk factor for ischemic stroke.[16,17]
Those ingesting pomegranate juice for one year experienced substantial improvements in carotid artery anatomy and function. Atherosclerotic lesions in the carotid artery were reduced by 35% in those who consumed pomegranate juice for one year. These improvements were accompanied by a 130% increase in total antioxidant status along with a 21% reduction in systolic blood pressure. By comparison, carotid artery narrowing in those who did not consume pomegranate juice increased by 9%.[16]
Researchers at the Preventive Medicine Research Institute in Sausalito, California, directed by Dean Ornish, M.D., gave pomegranate juice or a comparable beverage daily to 45 patients with coronary artery disease. After 3 months, pomegranate juice drinkers had a 17 percent improvement in blood flow compared to an 18 percent worsening in the control group. This benefit was irrespective of changes in cardiac medication, blood pressure, weight, or other factors. The study team concluded that the antioxidants in pomegranate juice may help prevent the formation of fatty deposits on artery walls.[18]
Other research confirmed that pomegranates reduced the effects of stress on human blood vessel cells by stimulating the production of nitric oxide. Human endothelial cells that line blood vessels were exposed to excessive physical stress, such as might occur with high blood pressure. Cells that were treated with pomegranate juice had less evidence of damage from the stress. In addition, animal experiments showed that pomegranate juice significantly slowed hardening of the arteries which developed from high cholesterol.[19,20] Researchers concluded that pomegranate juice not only appears to prevent hardening of the arteries by reducing blood vessel damage, but the antioxidant-rich juice may also reverse the progression of this disease. Similar results were seen with the administration of a pomegranate fruit extract.[21]
In another recent study with Type 2 diabetic patients, pomegranate antioxidants reduced the uptake of oxidized ―bad‖ LDL cholesterol by immune cells, which is a major contributing factor to atherosclerosis.[22]
Protection Against Prostate Cancer Prostate cancer is the second leading cause of cancer related deaths among U.S. males, with a similar trend in many Western countries. Even a modest delay in disease progression, however, could significantly impact the quality of life of these patients.[23] A 2007 study, published in the Journal of Agricultural and Food Chemistry, reports that the growth of prostate cancer cells was significantly inhibited by the pomegranate ellagitannins and their metabolites, showing the fruit’s potential against the disease.[24]
The authors of the study, led by UCLA researcher Dr. Navindra Seeram, wrote: We have shown that pomegranate ellagitannins metabolites are concentrated to a high degree in mouse prostate tissues. The current study contributes to the increasing body of evidence demonstrating the prostate cancer chemopreventive potential of pomegranate ellagitannins.[24]
Punicalagins in pomegranate account for much of the fruit’s antioxidant ability and the observed anticancer effects observed in this study. It appears that phytochemicals in pomegranate may also play a role in prostate cancer protection.[24]
Although conventional treatment for prostate cancer is often successful, a third of patients are reported to have rising levels of prostate-specific antigen (PSA) in their blood after treatment. Of these men, 34% progress to deadly, metastatic prostate cancer within 15 years.[25] UCLA researchers led by Allan Pantuck, MD, conducted a study on men who had undergone surgery or radiation, but quickly experienced increases in prostate-specific antigen or PSA, a biomarker that indicates the presence of cancer. The researchers measured ―doubling time,‖ how long it takes for PSA levels to double, a signal that the cancer is progressing. The men’s overall PSA doubling time was nearly four times slower after they began drinking pomegranate juice. Sixteen of the 46 patients had a decrease in PSA levels — and in four, PSA levels dropped by half.―I was surprised when I saw such an improvement in PSA numbers,‖ Dr. Pantuck said in a news release. ―This is not a cure, but we may be able to change the way prostate cancer grows.‖[26] Pantuck also believes that pomegranate juice may allow 65- to 70-year-old men treated for prostate cancer to outlive their risk of dying from their cancer.
Pomegranate Fruit Extract May Help Prevent Osteoarthritis Findings from preliminary lab tests show that natural antioxidants in pomegranate fruit may thwart osteoarthritis. In a recent study, published in the Journal of Nutrition, pomegranate fruit extract was pitted against osteoarthritis in lab tests and the results were impressive. Pomegranate fruit extract reduced levels of an inflammatory chemical called interleukin – 1β (IL-1β). It also curbed enzymes that erode cartilage.[2] Improved Immunity
The antimicrobial properties of plants are being studied by researchers worldwide. As a result, extracts or purified compounds from pomegranate are now known to possess antibacterial, antifungal and antiviral activities.[6] Pomegranate extract was found to act synergistically with antibiotics used to treat methicillin-resistant and methicillin-sensitive Staphylococcus aureus. Significant synergistic activity was detected between pomegranate and the five antibiotics tested: chloramphenicol, gentamicin, ampicillin, tetracycline, and oxacillin. Authors of the study concluded that pomegranate extract ―offers an alternative for the extension of the useful lifetime of these antibiotics.‖[28] More recently, findings from the Department of Pharmacognosy at the University of Mississippi have linked the daily intake of pomegranate antioxidants to beneficial effects for the human immune system.[29]
Choose a Natural-Spectrum Pomegranate Extract As previously mentioned, the health benefits of pomegranate are attributed to the high levels and diversity of the fruit’s unique phytochemicals. Of these natural protective ingredients, punicalagins have been established as the chemical marker compounds that should be used for the authentication, quality control and standardization of pomegranate products.[5]
Unfortunately, levels of pomegranate’s important antioxidant ingredients can vary widely in juices, depending on the fruit cultivar as well as processing and storage conditions. Also, there are limitations to using pomegranate juice for those concerned about sugar and caloric intake.[8] A clinically-tested, natural-spectrum pomegranate extract is now available, offering several advantages to consumers. This whole fruit extract, standardized for punicalagins, consistently provides the benefits of pomegranate without the sugar and caloric intake.
References 1. The Power of the Pomegranate: Biblical Fruit with Medicinal Properties, Horowitz S, Alternative & Complementary Therapies, 12(3): 121-6, 2006. 2. Punica granatum L. extract inhibits IL-1betainduced expression of matrix metalloproteinases by inhibiting the activation of MAP kinases and NF-kappaB in human chondrocytes in vitro, Ahmed S, et al, J Nutr, 135(9):2096-102, Sept 2005. 3. Trends: Join the fruit club, Barrett J, Newsweek, (10) January 23, 2006. 4. Pratt S, MD, Matthews K, Superfoods Healthstyle: Proven Strategies for Lifelong Health. New York: William Morrow, 2006. 5. Impact of Pomegranate Juice on Human Health and Diseases, WORLDNUTRA 2006, Reno, NV: 7th International Conference and Exhibition on Nutraceuticals and Functional Foods, Nov 7, 2006. 6. Seeram NP, Schulman RN, Heber D (Eds), Pomegranate: Ancient Roots to Modern Medicine, Boca Raton, FL: CRC Press & Taylor and Francis Group, 2006. 7. Pomegranate juice does not impair clearance of oral or intravenous midazolam, a probe for cytochrome P450-3A activity: comparison with grapefruit juice, Farkas D, et al, J Clin Pharmacol, 47(3):286-94, Mar 2007. 8. Absorption, metabolism, and antioxidant effects of pomegranate (Punica granatum l.) polyphenols after ingestion of a standardized extract in healthy human volunteers, Mertens-Talcott SU, et al, J Agric Food Chem, 54(23):8956-61, Nov 15, 2006. 9. Antioxidant Effects of Pomegranate in Healthy Volunteers, Milot B, HerbClip (HC 110161-318), American Botanical Council, Dec 15, 2006. 10. Cardiovascular disease: prevention and control, WHO, http://www.who.int/dietphysi calactivity/media/en/gsfs_cvd.pdf (Last accessed on Nov. 6, 2007). 11. The Top Ten Causes of Death, Fact Sheet, WHO, http://www.who.int/mediacentre/factsheets/fs310.pdf (Last accessed on Nov. 6, 2007). 12. What is atherosclerosis?, American Heart Association, http://www.americanheart.org/presenter.jhtml?identifier=4440 (Last accessed on Nov 6, 2007). 13. Guyton JR, MD, Atherosclerosis – A Story of Cells, Cholesterol, and Clots, http://www.lipid.org/clinical/patients/1000005.php (Last accessed on Nov 15, 2007). 14. Webb N, PhD, Arteriosclerosis, Thrombosis and Vascular Biology Annual Conference, American Heart Association, http://www.americanheart.org/presenter.jhtml?identifier=3043775 (Last accessed on Nov 15, 2007). 15. Plasma oxidized low-density lipoprotein, a strong predictor for acute coronary heart disease events in apparently healthy, middle-aged men from the general population, Meisinger C, et al, Circulation, 112(5):651-7, Aug 2, 2005. 16. Pomegranate juice consumption for 3 years by patients with carotid artery stenosis reduces common carotid intima-media thickness, blood pressure and LDL oxidation, Aviram M, et al, Clin Nutr, 23(3):423-33, Jun 2004.
