University of California

Nutraceuticals: Separating the wheat from the chaff


Andrea T. Borchers
Carl L. Keen
Judy S. Stern
M. Eric Gershwin

Authors Affiliations

A.T. Borchers is Postdoctoral Fellow, Department of Nutrition, UC Davis; C.L. Keen is Chair and Professor, Department of Nutrition, UC Davis; J.S. Stern is Professor, Department of Nutrition, UC Davis; M.E. Gershwin is Chief and Professor, Division of Rheumatology, Allergy and Clinical Immunology, UC Davis.

Publication Information

Hilgardia 54(5):26-32. DOI:10.3733/ca.v054n05p26. September 2000.

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Foods provide nutrients such as vitamins, minerals, protein, carbohydrate and fat and a host of other nonessential nutrients that may confer health benefits. Some “nutraceuticals” have been found to boost the immune system, enhance memory function and possibly slow the aging process. For example, flavonoids — which are found in red wine, purple grape juice, green tea and cocoa products — exhibit potent antioxidant activity in laboratory experiments and have been postulated to protect against coronary artery disease and reduce the risk of cancer. Recognizing potential health benefits from flavonoids and other plant extracts, some manufacturers are creating “functional” foods by fortifying, bioengineering and otherwise modifying foods so that they contain higher than normal concentrations of these components. With the exception of echinacea, St. John's wort and Ginkgo biloba, there is a paucity of scientific data for the majority of botanicals sold in health food stores and supermarkets. At the same time, adverse reactions to some botanicals have been documented in humans. Many would argue that government regulation of botanicals is inadequate. Further studies and comprehensive databases are needed to establish the safety and efficacy of popular and widely consumed dietary supplements.


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Borchers A, Keen C, Stern J, Gershwin M. 2000. Nutraceuticals: Separating the wheat from the chaff. Hilgardia 54(5):26-32. DOI:10.3733/ca.v054n05p26
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