Preservatives in Skin Care and Their Alternatives

Preservatives are widely used in skin care products to prevent bacterial, fungal, and mold growth, ensuring that products remain safe and effective for longer periods of time. However, preservatives – particularly parabens – have been a controversial topic due to rising concerns about potential health risks of these ingredients. As a result, many brands have shifted toward “paraben-free” products, using different preservatives instead of parabens. This, however, raises questions around the safety and efficacy of non-paraben preservatives.

Here, we break down the latest research on the role, safety, and efficacy of several types of preservatives to help you decide if paraben-free skin care is the best choice for you.

Preservatives are chemical compounds added to skin care products to prevent the growth of microorganisms such as bacteria, fungi, and mold. Because most skin care formulations contain water, they are susceptible to contamination, making preservatives essential for product safety and shelf stability. Without preservatives, many creams, serums, and lotions would have very short lifespans and could pose health risks due to bacterial growth.

Some of the most frequently used preservatives in skin care include:

• Parabens, such as methylparaben, propylparaben, butylparaben, ethylparaben - Once widely used, parabens are now controversial due to concerns about their estrogenic effects.

• Phenoxyethanol - This is a common paraben alternative that is effective against bacteria but does not prevent yeast and mold growth. Can cause skin irritation. 

• Benzyl alcohol - This is a naturally occurring preservative found in some essential oils. While it has natural antimicrobial properties, benzyl alcohol can be irritating to sensitive skin.

• Sodium benzoate and potassium sorbate- Often used in natural or organic skin care, these preservatives are more effective against fungi than bacteria.

• Formaldehyde-releasing preservatives, such as DMDM hydantoin, quaternium-15, imidazolidinyl urea, and diazolidinyl urea. These preservatives are highly effective but have raised safety concerns due to their potential to release formaldehyde , a known skin sensitizer and allergen.

Preservatives play an important role in maintaining the integrity and safety of skin care products. One of their primary functions is to extend the shelf life of products, preventing spoilage and ensuring that products remain effective over time.

Because most skin care products contain water, they create an environment where bacteria, yeast, and mold can thrive. Preservatives help to prevent microbial contamination, which could otherwise lead to infections, allergic reactions, or other adverse effects. Without them, many skin care products would need to be refrigerated or would have a much shorter shelf life, making them less practical for daily use – not to mention difficult and expensive to manufacture, store, and ship.

In recent years, preservatives like parabens have been under scrutiny for their potential adverse effects. As a result, many brands have reformulated their products to be paraben-free. However, the effectiveness of alternative preservatives varies, and some may not offer the same level of microbial protection. The challenge in formulating safe and effective skin care products lies in finding preservatives that balance both safety and efficacy without causing irritation or compromising product stability.

Parabens are a specific type of preservative that have been widely used in personal care products for decades. They are alkyl esters of p-hydroxybenzoic acid , found naturally in foods like raspberries, carrots, and cucumbers.

Despite their long history of safe use, parabens have come under scrutiny due to concerns about their ability to mimic estrogen, leading to fears about potential links to breast cancer and reproductive health issues. However, the latest research has found that this estrogenic activity is very weak , and there have been no established reports of an estrogenic-related adverse event in humans caused by parabens (3)

While many skin care brands have removed parabens due to consumer demand, the alternatives are not always better. Some commonly used replacements such as benzyl alcohol can cause skin irritation, while others may be less effective at preventing microbial contamination.

• Effectiveness. Parabens are highly effective at preventing bacterial and fungal growth, whereas many paraben-free alternatives struggle to provide the same level of protection.

• Allergic reactions. Despite concerns, parabens have one of the lowest rates of allergic reactions among preservatives. In fact, the American Contact Dermatitis Society named parabens the “(non)-allergen of the year” in 2019 due to their low irritation potential (4). Many paraben-free preservatives, such as formaldehyde releasers, are more likely to cause contact dermatitis.

• Safety on intact skin. Parabens are safe for use on healthy, intact skin. However, they should not be applied to damaged or broken skin, where they can cause irritation. This also applies to other types of preservatives.

The safety of preservatives depends on the type used, the concentration, and the specific formulations. While parabens in particular have come under fire for safety risks, the latest research shows that parabens are likely much safer than has been recently thought, and paraben alternatives may pose greater safety risks.

Some non-paraben preservatives, for example, can release formaldehyde, while others are less effective at eliminating bacteria, yeast, and mold, which can cause other health risks.

While some parabens have been shown to exhibit some estrogenic effects in vitro (in test tubes), studies have shown that these effects are very weak – 10,000 times weaker than natural estrogen. Thus, the Cosmetic Ingredient Review (CIR) panel concluded in 2018 that there is no substantial evidence linking parabens in reproductive harm or skin cancer (5).

It is, however, important to note that parabens and other preservatives should only come into contact with healthy, intact skin to minimize the risk of irritation and potential allergic reactions.

Recent research has clarified some of the misconceptions surrounding preservatives in skin care:

• Parabens do not accumulate in the body. They are absorbed through the skin and excreted quickly through urine (5).

• Parabens have a lower allergenic potential than many paraben-free preservatives (6).

• There is no proven link between paraben use in skin care and cancer. The geographic distribution of breast cancer cases does not correlate with paraben exposure levels (5, 7).

• New preservative options are being developed that have reduced allergenic potential and no estrogenic activity.

• Organic products without preservatives are improving in efficacy, but they still have a shorter shelf life and higher risk of microbial contamination.

Many products are now paraben-free. As we discussed above, however, you still have to be on the lookout for other preservatives that can cause allergic reactions and other unwanted side effects. However, if buying paraben-free skin care is important to you, the good news is you have a growing list of great brands to choose from. Just a few top paraben-free products include:

While preservatives are essential for keeping skin care products safe, not all preservatives are created equal. Parabens, despite their bad reputation, remain one of the safest and most effective preservatives in skin care. Many paraben-free alternatives are more likely to cause allergic reactions and may not protect against bacteria, yeast, and mold as effectively.

If you have sensitive skin, the best approach is to choose products carefully, paying attention to preservatives in the ingredient list. Always use skin care products on intact skin to avoid irritation, and be sure you are using products that are correct for your skin type.

1. Weisberg E., Baumann L. Preservatives in Ch. 44 of Baumann's Cosmetic Dermatology Ed 3. (McGraw Hill 2022)
2. Baumann, L. Cosmeceuticals and Cosmetic Ingredients (McGraw Hill 2015)
3. Soni MG, Carabin IG, Burdock GA. Safety assessment of esters of p-hydroxybenzoic acid (parabens). Food Chem Toxicol. 2005;43(7):985-1015.

4. Fransway AF, Fransway PJ, Belsito DV, Warshaw EM, Sasseville D, Fowler JF Jr, et al. Parabens. Dermatitis. 2019;30(1):3-31.

5. Heldreth B. CIR Conclusion: Parabens Are Safe. Cosmet Toilet. November 16, 2018. https://www.cosmeticsandtoiletries.com/regulatory/region/northamerica/CIR-Conclusion-Parabens-Are-Safe-500174801.html.

6. Sasseville D. Hypersensitivity to preservatives. Dermatol Ther. 2004;17(3):251-63.

7. Darbre P. Underarm cosmetics and breast cancer. Eur J Cancer Prev. 2004;13:153.