Parabens are preservatives that are commonly used in skin care products. They have come under fire by some groups in recent years because they have weakly estrogenic activity. That means that they have qualities that weakly mimic estrogen, one of the predominant female hormones. A few small studies have found traces of parabens in breast cancer specimens. The methodology of these studies has been criticized by numerous scientists.
To put things in perspective, the estrogenic activity of various parabens is thousands of times less than that of estrogenic substances found in foods such as soybeans or chickpeas, and about 10,000 times less than that of estrogen that is naturally produced in the body. Numerous toxicology tests have shown that parabens have low toxicity. They are also non-irritating and have a low risk of causing allergic reactions. The FDA states that levels of parabens used in all products do not come close to unsafe levels.
Preservatives like parabens are important because they extend the shelf-life of our products. Parabens work by stunting the growth of bacteria and fungi. Without preservatives, skin-care products would become overgrown with these organisms and would spoil quickly.
In response to public interest, many companies now offer paraben-free products. If you choose to avoid parabens in skin care products, you can do so by checking labels. Commonly used parabens found in skin care products include propylparaben, ethylparaben, methylparaben and butylparaben. It should be noted, however, that parabens in "paraben-free" products are frequently replaced by preservatives known as "formaldehyde releasers", which may be more likely than parabens to cause allergic reactions.