Recently, there has been a rise in the number of Internet ads promoting herbal breast enlargement. The ads are enticing, offering a non-surgical, "natural" way to increase breast size and firmness. They cite health experts and scientific research.

Does it sound too good to be true? Let's examine the issue:

1. What are some of the claims?

"Our formula is based on scientific research and has been proven to be effective."
"...a fuller, firmer, more beautiful bust-line, with no adverse side effects."
"By balancing and regulating hormones, this herbal formula works with your own body to safely regenerate real tissue growth internally, producing larger, fuller, firmer, and healthier breasts."
"This mastogenic effect has long been known and used in various cultures throughout the world dating back to the harem girls in the middle east."
"When you want a natural breast enlargement formula for a fuller, firmer, more beautiful bust line hormone balancing is the first step every woman should take."
"Within eight weeks, busts became firmer; fuller and increased at least one bra cup size."
"Let's be honest -- appearance is much more important today than many people would like to believe."

2. How do they work?

The products use herbs and food plants containing compounds that have hormone-like activity, either directly or upon being metabolized. One key ingredient is saw palmetto (Serenoa repens), a herb that is best known as a treatment for benign prostate enlargement in men.
Saw palmetto has also been noted to increase breast size but its effects on the female body are poorly understood. Saw palmetto's ability to increase breast size is believed by some to be augmented when combined with other herbs such as wild yam, fennel and fenugreek.

3. What research has been done on these products?

There are very few published research studies examining the side effects and risks of using these herbs. Some companies claim to have conducted their own research, however, this information has not been published in medical journals so the quality and details of the studies are not known.

4. What are the side effects and risks?

We know that excess exposure to hormones such as estrogen promotes cancer. Although plants with hormone-like effects often protect against cancer, the herbs in these products have not been shown to be safe at the doses that these companies are recommending.

One study found that after consuming fennel seed for 10 days, the mammary gland weight of female rats increased. Higher doses increased the weight of the uterus.

So it is not known whether these products taken at their recommended doses can promote endometrial tissue growth or increase the risk of breast or endometrial cancer. If so, women with endometriosis, gallbladder disease, fibrocystic breast, women who are pregnant, nursing, at risk of breast cancer or taking oral contraceptives or hormone replacement therapy may have an even greater risk.

The verdict is? Until research studies examining the short- and long-term risks are published, herbal breast enlargement products should be avoided.