However, Independent Study Finds That All Isoflavone Supplements are Not Created Equal

(ARA) - As baby boomers age, large numbers of women are entering menopause. Doctors often prescribe hormone replacement therapy (HRT) to alleviate symptoms associated with menopause. However, more and more women prefer to try other therapies as an alternative to conventional HRT.

"Many women are turning to products containing phytoestrogens in an attempt to reduce menopausal symptoms such as hot flashes, night sweats, as well as slow the rate of bone loss and reduce cholesterol," said Lila Nachtigall, M.D., professor of OBGYN at the New York University School of Medicine, and director of the NYU Medical Center's Women's Wellness Center. "Phytoestrogens come from plants including soybeans and red clover. Isoflavones are a type of phytoestrogen that resembles human estrogen. They may help offset the drop in estrogen and regulate its fluctuations that occur at menopause."

Because it is difficult for a woman who eats a typical American diet to consume enough isoflavones through food alone, many women turn to supplements to get to beneficial levels. According to the National Consumers League, women in the United States spend approximately $200 million per year on non-prescription dietary supplement therapies for menopausal symptoms.

Unfortunately, it can be almost impossible for consumers to know what they are getting in their supplements.

Recent studies show that many dietary supplements are mislabeled and have different amounts of active ingredients from what the manufacturer claims on the label. Unfortunately, according to a recent study, this practice holds true for some dietary supplements containing isoflavone-based ingredients. The results of an independent study, funded by the National Institute of Health, were reported in a recent peer-reviewed article in the Journal of Nutrition. To confirm that the manufacturers label claims were accurate the study analyzed the isoflavone content of known active phystoestrogens for 33 products sold in the U.S.

"It is evident that for a high proportion of these products, the consumer should have little confidence in what they are purchasing," say the authors of the study.

"These supplements are intended to provide phytoestrogen support to women," said Dr. Nachtigall.

However according to the study, just seven of 33 products were within 10 percent of their label claim and only one -- Promensil -- delivered the isoflavones in the readily bio-available form.

Women taking many of these products may be receiving phytoestrogens well below effective levels and possibly of no true benefit. "Our studies of a selection of commercially available over-the-counter phytoestrogen supplements show that there is a wide variation in composition and that no two supplements appear to be the same. This poses some difficulties for the consumer as to what supplement is 'best' to purchase," according to the study.

Promensil, manufactured by Australia-based Novogen, contains isoflavones derived from specially cultivated red clover. Promensil is standardized to deliver the claimed dose in every tablet. Products that are not standardized can vary significantly in the amount of active ingredient. Additionally Promensil provides four important dietary plant estrogens: formononetin, biochanin and the two contained in soy: genistein and daidzein.

The NIH-funded study also found that a number of the labels for the supplements promote soy content, and yet only a very small percentage of content appears to come from soy plants. A close review of the labels reveals that many contain isoflavones derived from kudzu (often identified by its Latin name, pueraaria lobata root extract). While there may be some soy isoflavones in these products, the major source of isoflavones is likely kudzu, the pest plant seen strangling natural vegetation in the Southern United States.

Consumers need to be informed to ensure they are making wise health decisions, including the safe and effective use of dietary supplements. Promensil can be purchased in the dietary supplement section of pharmacies and health food stores nationwide. For more information on Promensil, call (877) 4-1-Promensil (417-7663).