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By the way, doctor: Do breast-enhancement supplements work?

By the way, doctor

Do breast-enhancement supplements work?

Q What can you tell me about natural hormonal and herbal preparations advertised to enlarge breasts? Do they work, and are they safe?

A Dietary supplements for enhancing breast size are often marketed with compelling testimonials and results from so-called scientific studies. But no clinical trial data have been published on any of these products, so we have no proof that they work.

Estrogen and progesterone are the only natural hormones we know of that increase breast size. But as you may know, studies have linked excess estrogen and progesterone with breast cancer, heart disease, and stroke in postmenopausal women. These hormones may be prescribed in medications such as oral contraceptives and postmenopausal hormone therapy, but they’re not approved for breast enhancement.

That leaves a variety of “natural” breast-enhancement products that don’t require a prescription or FDA approval. The ingredients usually fall into one of several categories: phytoestrogens (plant-derived chemicals such as soy, flaxseed, red clover, alfalfa, and fennel), alleged aphrodisiacs (such as damiana or oat straw), and herbs traditionally used for women’s menstrual or reproductive complaints (including blessed thistle, motherwort, black cohosh, chaste-tree berry, and saw palmetto).

Of these plant products, phytoestrogens are the ones most likely to actually affect breast size because they attach to estrogen receptors on cells, producing weak estrogenic effects. But in premenopausal women, such effects could theoretically interfere with normal estrogenic stimulation and growth of breast tissue.

Phytoestrogens may increase breast size in postmenopausal women, whose baseline estrogen levels are low, but it may be at a price: Any supplement containing enough phytoestrogen to stimulate breast tissue growth might also increase the risk of breast cancer.

There are other potentially harmful effects. Some herbs may cause bleeding, which can be dangerous for women taking blood-thinning medications such as warfarin (Coumadin). Others can affect blood sugar levels. And many herbal ingredients interact with other medications.

In sum, we have no evidence that breast-enhancement supplements work or that they can be taken safely. We’ll probably never know the truth, because supplements such as these aren’t required to undergo rigorous evaluation, as conventional drugs are, before they can be approved for widespread use.

— Celeste Robb-Nicholson, M.D. Editor in Chief, HWHW

Last updated:	August 21, 2006