The Role of Phytoestrogens in the Prevention and Treatment of Osteoporosis in Ovarian Hormone Deficiency

Abstract

Ovarian hormone deficiency is a major risk factor for osteoporosis in postmenopausal women. Hormone replacement therapy (HRT) is perhaps the most effective treatment, as it has been demonstrated to both reduce the rate of bone loss and risk of fracture, including hip fracture. However, not all women who may benefit from HRT are willing to initiate this treatment due to fear of cancer and contraindications. Other therapeutic agents currently available are also associated with certain adverse effects. As a result, postmenopausal women are more inclined to use natural remedies to alleviate postmenopausal symptoms and help reduce their risk for chronic diseases such as osteoporosis. Recent reports support the notion that certain bioactive constituents, e.g., phytoestrogens, in plants play a role in maintaining or improving skeletal health. The main consumable plant sources of phytoestrogens include isoflavones and lignans found mainly in soybeans and flaxseed, respectively. Although this paper primarily focuses on the effects of soy protein or its isoflavones on bone, additional statements regarding the role of flaxseed and dried plums, a rich source of polyphenols, with respect to bone will be made.

• soy protein
• isoflavones
• flaxseed
• dried plums
• osteoporosis

Key teaching points:

• Isoflavones are a diverse group of compounds that have weak estrogen-like properties and are often referred to as phytoestrogens.

• Soybeans are a rich source of the isoflavones genistein and daidzein.

• Flaxseed is the richest source of mammalian lignan precursors, enterodiol and enterolactone.

• Dried plums are a good source of dietary fiber and contain a number of phenolic compounds that may act as powerful antioxidants.

Key teaching points:

• Isoflavones are a diverse group of compounds that have weak estrogen-like properties and are often referred to as phytoestrogens.

• Soybeans are a rich source of the isoflavones genistein and daidzein.

• Flaxseed is the richest source of mammalian lignan precursors, enterodiol and enterolactone.

• Dried plums are a good source of dietary fiber and contain a number of phenolic compounds that may act as powerful antioxidants.

These studies have been supported, in part, by grants from NIH R03-AG16487-01, Illinois Soybean Program Operating Board, and California Dried Plum Board.

Notes

Presented in part at Ross Products Research Conference on Medical Issues, “Synergy in Medical and Nutritional Therapy,” November 6–8, 2000, Key Largo, Florida.