Style Skincare 12 Common Skincare and Cosmetic Ingredients Derms Want You to Avoid How many of these harmful ingredients are lurking in your favorite products? By Sharon Feiereisen Sharon Feiereisen Sharon Feiereisen is a freelance lifestyle writer. Her work has been published in Time Out, Newsday, The Knot, Teen Vogue, Business Insider, and Hamptons Magazine among many other print and online outlets. Real Simple's Editorial Guidelines Updated on November 10, 2022 Fact checked by Danielle Slauter Fact checked by Danielle Slauter Highlights: * Has worked as a fact checker for Real Simple since 2022 * Worked as a staff writer for Mochi Magazine * Currently runs and operates the United States blog for Student Beans Our Fact-Checking Process Share Tweet Pin Email When shopping the aisles for beauty products, remember one thing: Just because it's sold on a shelf in a reputable store doesn't make it safe. (Let's not forget the long history of lead being used in the cosmetic industry.) It can be difficult to navigate and decipher the long list of ingredients on most beauty product labels. Thankfully, there are sites and apps that can help make the process easier. EWG's Skin Deep database allows you to search for cosmetic ingredients and products to see if they meet the non-profit's strict criteria. There are also apps, like Yuka, that allow you to scan a product to find out if it contains any endocrine disruptors, carcinogens, allergens, or irritants. Unfortunately, it doesn't cover all products, so when in doubt, rely on this dermatologist-backed cheat sheet of harmful ingredients before reaching for your credit card. 01 of 12 Chemical Sunscreen A recent study showed that six common chemical sunscreen ingredients absorb into the bloodstream and greatly exceed levels considered safe. "One ingredient—oxybenzone—showed an absorption rate 188 times the safe level after one application," says Dennis Gross, MD, a dermatologist and dermatological surgeon. "After four applications, absorption increased 500 times the safe level. All chemicals stayed elevated in the blood anywhere from one to 21 days, depending on the chemical sunscreen ingredient." It has been well established that oxybenzone is an endocrine disrupter, which can have serious consequences on fertility. Moreover, chemical sunscreen should be avoided during pregnancy as it has been linked to birth defects. The American Academy of Pediatrics also recommends that parents don't use sunscreens with oxybenzone on kids. Instead, Dr. Gross recommends opting for mineral sunscreen, which sits on the surface of the skin and isn't absorbed. The active ingredients in these safe sunscreens are zinc oxide and/or titanium dioxide. RELATED: 15 Best Mineral Sunscreens 02 of 12 Methylisothiazolinone Methylisothiazolinone is a preservative found most often in water-based products like shampoos and cleansers. "Even though it's used in small concentrations, it's still a strong allergen and can cause burning, itching, or even hives," says Marie Hayag, MD, a dermatologist and founder of 5th Avenue Aesthetics. "Those with sensitive skin should avoid this ingredient altogether, especially when it comes to leave-on products." 03 of 12 Sodium Lauryl Sulfate Sodium lauryl sulfate is a very common cleansing agent. "It's found in a wide array of personal care items, including shampoos, cleansers, and body washes," says Dr. Hayag. "It frequently causes irritation and can also elicit an allergic response in the skin. If SLS is not washed off properly, its residue can leave your skin dehydrated and reduce the levels of ceramide in your skin." She suggests looking for products that have fatty alcohols instead. "Castile-based soaps or cleansers are good alternatives," she says—a great body wash to try is Seven Minerals. When it comes to makeup brush cleaners, choose one like Ecotools which uses citric acid instead to wick away dirt and impurities. 04 of 12 Acrylates (Ethyl Acrylate, Ethyl Methacrylate, and Methyl Methacrylate) Acrylates are mainly found in artificial nail products and false eyelashes where they're used as adhesives. They can cause contact allergies in a relatively high number of people, according to Dr. Hayag. "Different acrylates are also associated with different concerns, including possibly being carcinogenic," she says. "Since practically all artificial nail products contain some form of acrylate, it's best to either avoid them altogether, or at least lower your use of them." 05 of 12 Parabens Parabens are one of the best-known no-no ingredients, and yet these preservatives, derived from petroleum, are still incredibly pervasive. Not only are there links to breast cancer, they are known endocrine disruptors, meaning they mimic estrogen in the body, which can lead to hormonal imbalances and infertility. "Parabens can be listed under different names, but the most common are methylparaben, propylparaben, butylparaben, and ethylparaben," says Debra Jaliman, MD, a dermatologist and author of Skin Rules: Trade Secrets from a Top New York Dermatologist. According to Dr. Jaliman, parabens are particularly common in makeup and moisturizers. 06 of 12 Coconut Oil Coconut oil has been widely touted as an effective spot treatment for acne (among many other things), but Howard Sobel, MD, founder of Sobel Skin and attending dermatologist and dermatologic surgeon at Lenox Hill Hospital, says it actually makes the breakout worse by clogging surrounding pores. While he advises against applying pure coconut oil, he also advises against products—like face masks and moisturizers—formulated with coconut oil. "Even in those small concentrations, it can still be irritating, so it's better to just avoid altogether." 07 of 12 Fragrances Many of us consider a good smell a deciding factor when choosing skincare, but we should actually be making sure that no synthetic fragrances have been added before sniffing anything. "The vast majority of products contain purely chemically produced fragrance compositions, which have been shown to cause allergic reactions on the skin, along with headaches, allergies, dizziness, rashes, cough, skin irritation, pigmentation, and hyperactivity," says Anne-Claire Walch, PhD, pharmacology expert and founder of Brûmée. "Manufacturers use thousands of fragrance components in their products, and unfortunately, there's no regulation to make it mandatory to list all components." If you have sensitive skin, particularly around the delicate eye area, look for an eye cream Avène, which is fragrance-free. 08 of 12 Formaldehyde Formaldehyde is popular in hair straightening products, nail polish, and other cosmetics, but Dr. Sobel says it should definitely be avoided, especially in skincare. "It's sometimes used as a chemical preservative to prevent bacterial growth, but if humans are exposed to high amounts of this, it has been thought that it puts you at higher risk for developing cancers," he says. 09 of 12 Toluene Toluene is a chemical commonly found in nail polish and hair dyes. "It's a volatile petrochemical solvent that can be toxic to the immune system and can cause birth defects," says Michele Green, MD, a cosmetic dermatologist. 10 of 12 Phthalates Used in cosmetics, primarily in fragrances, phthalates can also be found in skincare products. "They're known endocrine disruptors, which also cause hormonal and reproductive problems and birth defects," says Dr. Green. 11 of 12 Triclosan Triclosan is something many of us have been heavily exposed to, as it's found in antibacterial soaps. "Triclosan should be avoided because it causes antibiotic-resistant bacteria, and it's also known to disrupt the endocrine system," says Dr. Green. 12 of 12 Mineral Oil This common ingredient found in your makeup, SPF, and cleansers is a byproduct of petroleum. "It can contain carcinogenic chemicals, which as we've learned from formaldehyde, is thought to put humans at a higher risk for cancer if used in high amounts," says Dr. Sobel. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit Sources Real Simple is committed to using high-quality, reputable sources, including peer-reviewed studies, to support the facts in our articles. Read our editorial guidelines to learn more about how we fact check our content for accuracy. 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