Marmur Medical Blog

Parabens: Fact or Fiction?

Parabens are conspicuously “not” everywhere. Walking down any pharmacy aisle, one is assaulted by the number of labels boasting “paraben-free” labels. In an earlier article I had tackled the issues and non-issues regarding a number of other cosmetic additives and realized my glaring error in omitting parabens. Are parabens really dangerous enough to remove from all cosmecuticals?

Parabens are chemical derivatives of para-hydroxybenzoic acid. They are often used in products such as cosmetics, moisturizers, toothpaste, shampoo, and shaving gel. In addition to these regular consumer products, parabens may often be found as an ingredient in topical prescription drugs (drugs in lotion or drop form). However, paraben addition is not just limited to the cosmetic world, in fact, parabens can be found in many processed foods as well as naturally in others (blueberries have a relatively high content of nethylparaben). When combined with other preservatives, parabens are active discouragers of bacterial and fungal growth, thus protecting both the product and the user from microbial infection. By using a combination of preservatives, it allows manufacturers to use less parabens and decrease any associated risks.

The three most common parabens in cosmetics are methylparaben, propylparaben and butylparaben. Animal studies have indicated that paraben toxicology overall is minimal as these compounds are absorbed and then excreted as modified metabolites with very complicated, long names (so for our purposes we will know them as M1-M4). However, though they are excreted, the mere fact that the parabens are first absorbed means they can exert some biological effect on the human body.

Estrogens are the primary female sex hormones responsible for the onset of puberty and growth of hormone-sensitive/hormone-receptor positive breast cancers. Parabens happen to be xenoestrogens and therefore have the capability to act on the same cellular signaling pathways as estrogen. This being said, parabens have a greatly-reduced biological activity compared to inherent human estrogens. For instance, butylparaben, widely considered the most potent estrogen-imitator has an activity 10,000 to 100,000 times less than estradiol (a naturally produced estrogen compound), when used at concentrations 25,000 times less than found in cosmetics. Furthermore, it was found that these studies conducted outside the body had three times higher estrogen activity than when conducted within the body. To sum this science stuff up, it means at concentration way below those found in cosmeceuticals, the estrogen-like properties of parabens exert little to no effect in the human body.

So here comes the big question: do the use of parabens in cosmetics (and other products, let us not forget) put consumers at a higher risk for breast cancer? The short answer is maybe. The long answer involves studies showing that there is indeed parabens present in breast tumors (especially methylparaben) and that these parabens were most likely from a topical origin (i.e. paraben-containing creams, cosmetics, deodorant, antiperspirants). In addition, the use of paraben-containing deodorant and shaving under the arms may result in a diagnosis of breast cancer at an earlier age. There seems to be an association between paraben-containing products and breast cancer development and some scientists believe that the increased amount of parabens in consumer products may be correlated to the overall rise in the incidence of breast cancer.

In addition to breast cancer, some studies point to increased keratinocyte harm with exposure to UVB when using topicals containing methylparaben. Sunlight exposure causes altered metabolism of methylparaben by skin esterases, producing photo-metabolites such as 3-hydroxy methylparaben. These metabolites are further broken down causing oxidative DNA damage in skin cells. As I have harped on for many months, with sun damage and DNA mutation comes skin cancer. There may be an association between paraben-containing products and skin cancer though more research must be done on the subject to reach any conclusions.

However, it is prudent to note that government bodies dedicated to researching toxicity of additives have found that consumer safety is ensured if paraben content in cosmetics is below 25%, (in 2005 and later 2008, the safety of parabens was reassessed and it was found that there was no need to redefine parameters due to the continued low paraben-content of cosmetics). Actually, cosmetics contain 0.01%-0.3% paraben, levels well below that dictated by governmental regulations. With the low concentration of parabens in cosmetics, it is unlikely that parabens will penetrate the skin barrier to accumulate in tissue without being rapidly metabolized and excreted. Based on the maximum possible daily exposure limits of parabens, and taking into account that most cosmetics are well below these limits, it is thought that the health risks of paraben exposure from cosmetics are minimal.

As with any research subject regarding additives and the human body, there needs to be more research completed to really determine if there are paraben-related detrimental effects. So with that, it does no harm to go paraben-free. However, choices do become limited when you eliminate one of the most common cosmetic additives in the industry. Taking into account the extremely low dose of paraben in any cosmeceutical, it is probably safe to continue your life of guilt-free makeup.

Written by:
Margit Lai Wun Juhasz
Mount Sinai Medical Student