Of Spices and Fruits and WineFrom the UMKC Department of Surgery, Kansas City, Missouri Correspondence: Charles W. Van Way II, MD, UMKC Department of Surgery, 2301 Holmes Street, Kansas City, MO 64108. Electronic mail may be sent to vanway.charles{at}tmcmed.org. In this issue is a review by Bengmark,1 which catalogs the many and varied actions of curcumin. Now, curcumin is a common spice—it's found in curry powder and turmeric—yet it appears to have a wide variety of metabolic actions. Dr Bengmark communicates his enthusiasm for its beneficial actions in several chronic diseases. Curcumin may be an ingredient of folk remedies across Asia. But to us in the West, that's considered, as my old partner used to say, "woo-woo medicine." This is a scientific journal. Why should we, as nutrition scientists, be concerned about such things? Let us look a little farther. In a recent paper, dietary phytoestrogen intake has been shown to confer a remarkable degree of protection against the development of lung cancer, even in heavy smokers.2 This lowers the risk of lung cancer by up to 50%. Even nonsmokers appeared to lower their (already tiny) chances of contracting lung cancer. Significantly, dietary phytoestrogens were found to work proportionately; that is, risk reduction was greater in each quartile of progressively increasing intake. Consider that phytoestrogens are found in fruits and vegetables, for the most part. So should all smokers gorge on fruits? Eat cranberries with cigarettes? The images don't fit. The thing is, we already know how to reduce the chance of lung cancer: just don't smoke. The significance of the findings about dietary phytoestrogens is not that fruits and veggies are good for you but rather that a specific substance in them is beneficial in a very specific way. This is of considerable interest. Phytoestrogens are a family of compounds that share estrogenic properties. Not only does this finding have immediate clinical applicability, it points research on the pathogenesis of lung cancer in a new direction. As an example, it was found that women taking estrogens appeared to obtain an additive effect. Estrogen receptors have not been a prominent subject for lung cancer research, yet perhaps they should be. OK, let's get to red wine. More than 10 years ago, Renaud and de Lorgeril3 coined the phrase "the French paradox" to reflect the seeming contradiction between high levels of saturated fats in the French diet and low levels of ischemic heart disease. Although this was attributed by Renaud and de Lorgeril3 to the antiplatelet effects of alcohol, it is appears to be more specifically due to red wine. Across Europe and America, it has been established that the more red wine is consumed, the lower the observed mortality from ischemic heart disease.4 But what makes red wine different? It turns out that red wine contains high levels of polyphenols, both flavonoids and nonflavonoids. As compared with white wine, red wine contains around 1.8 g/L of these polyphenols, whereas white wine contains only 0.2–0.3 g/L. Specific polyphenols have been shown to induce lipid peroxidation of low-density lipoprotein, inhibit smooth muscle proliferation, decrease platelet adhesiveness, and even relax the small arteries.4 A number of these compounds have been studied individually. One of the nonflavonoids, resveratrol, appears to be particularly effective on platelets and also appears to have antioxidant activity. In a study from Turkey, resveratrol was found to be highly protective in a rabbit model of spinal cord ischemia.5 Its effect was attributed to its antioxidant activity and its stimulation of nitric oxide. There is considerable interest in this area. A PubMed search revealed 193 papers in the past 15 years on various aspects of red-wine polyphenols. Mining folk medicine for valuable drugs is an old story. Drugs like digitalis and quinine were known and developed long before the days of modern biomedical research. But the methods that are now available for the study of these agents are far more powerful and sophisticated than the observational tools available to our professional ancestors. We are now in a position to dissect out individual compounds from the many components of foods as complex as spice or red wine, or to determine beneficial components of a whole class of foodstuffs. There is a great deal that is yet to be discovered both in terms of potential therapeutic agents and expanding our understanding of how diet can affect disease. Or, putting it another way, the mechanism by which these food components act is a fruitful subject for nutrition research. Received for publication October 10, 2005. Accepted for publication October 10, 2005.
Journal of Parenteral and Enteral Nutrition, Vol. 30, No. 1,
61-62 (2006)
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cyclooxygenase-2, lipooxygenase, and inducible nitric oxide synthase
inhibitor: a shield against acute and chronic diseases. JPEN J Parenter
Enteral Nutr 2006;30:45
–51.