What Is Dimethicone & Is It Bad For Skin & Hair? Let's Investigate The Ingredient
When it comes to buzzy beauty ingredients, there's one famous (or infamous, depending on your worldview) player found in a slew of beauty products but isn't always referred to as the good guy. Enter, dimethicone. It sounds science-y (note: It is), and chances are if you do a quick Google search, you'll find a ton of conflicting information that will leave you a bit unsure.
Should you steer clear of this ingredient altogether or hoard every product that has it listed on the label? (Spoiler: While not harmful, we believe you should treat it with caution.)
Below, we tapped experts to get to the bottom of the dimethicone debate.
What is dimethicone?
According to cosmetic chemists Victoria Fu and Gloria Lu, founders of Chemist Confessions, dimethicone is a type of silicone. "It can come in various polymer sizes and range from a thin fluid to a thick and gooey consistency," they say. They continue that it's often used to help create an elegant formula that feels great on the skin (and hair).
Board-certified dermatologist Dendy Engelman, M.D., agrees: "It's popularly used in hair and skin care products as a smoothing and occlusive ingredient," she says. "You may be able to recognize the presence of dimethicone in your products by the silky-smooth texture that it adds." Essentially, it helps the formula to feel and perform more luxuriously.
Why is dimethicone in my skin care products?
The main reason? Texture, texture, texture. Soft, smooth, and silky texture makes a skin care product super appealing, and it makes the experience of using it more, well, luxurious and enjoyable.
Engelman says it's also used to create a protective barrier on the skin that blocks external agents like arid air and pollutants from reaching the skin while locking in moisture. In fact, one study found that a majority of skin care products use dimethicone for its moisturizing capabilities1—while it doesn't deliver any benefits from a skin-health perspective, per se, it forms an occlusive layer to keep moisture in and helps keep the surface of the skin soft and smooth.
Why is dimethicone in my hair care products?
When it comes to hair care, this silicone is a powerhouse at detangling and smoothing. "Dimethicone smooths down and binds the cuticles to the hair strand and gives the hair a silky texture and shine," Engelman says. (A coveted hair goal, no?) Not to mention, it's pretty inexpensive to formulate with—so it's no surprise that it's a popular ingredient among a wide range of hair care formulas.
Is it bad for skin and hair?
There's lots of talk about the good, bad, and ugly of including silicones like dimethicone in your beauty routine. And the truth is: Not all silicones are created equal. See, some silicones (cyclosiloxanes D4 and D5, specifically) are shown to be potentially hazardous for human health and can also bioaccumulate in our water supply2. But researchers were able to develop water-soluble silicones that are generally fine to use: They are easier to remove, aren't as sticky of an occlusive, and don't bioaccumulate. Dimethicone falls into that latter category.
However, there are a few reasons even water-soluble silicones can get a bad rap—one of the most commonly cited is because of its occlusive properties.
"Dimethicone is often accused of 'suffocating' skin," Fu and Lu say, which isn't always the case—for some, especially those with drier skin types, locking in moisture is just what they need. (Of course, natural oils can effectively do the same thing and simultaneously feed the skin with antioxidants, fatty acids, and amino acids. But a product with dimethicone can provide occlusive benefits.)
Although, Engelman adds that dimethicone can irritate those with sensitive skin since silicones can cause irritation; and for those with acne-prone skin, it can create the perfect environment for breakouts. "Breakouts can occur when silicone builds up on the skin's surface and traps bacteria, dirt, and pollutants in, clogging your pores," Engelman warns. She continues that it can also interfere with natural processes like sweating and releasing unwanted dirt and bacteria from the pores since it creates a film over the skin.
As for the hair, Engelman says using silicones, like dimethicone, can build up easily in the hair and block water and nourishment from getting past the protective outer cuticle. This eventually can make the hair dry and brittle, and it may even weigh the hair down and make it appear flat. "Those with curly hair and fine hair should be careful of this," she warns.
As Ron McLaughlin, vice president of research and development at Living Proof, previously told mbg about silicone buildup in hair care: "The obvious drawback of all this is that you end up with hair that gets weighed down or greasy, so you are more likely to shampoo and style more often. This perpetuates what we call the cycle of damage. The more you wash and style, the more damaged your hair is, so the more you will feel like you need to reach for a silicone to get that soft feeling again. It's a vicious cycle."
So, should you steer clear of dimethicone?
Well, it's hard to say. We need more research to make the call, but all three experts agree that dimethicone is (generally) nothing to worry about, so long as you make sure you're properly cleansing your hair and skin to avoid buildup. "The amount of dimethicone in your beauty products is often very minimal and not harmful to the body," Engelman says. "Although an excess of this ingredient is not recommended, you don't need to be alarmed if you see it in your products."
Fu and Lu add, from a formulator perspective, dimethicone is a great ingredient to include for its silky texture: "It can help create a beautiful moisturizer suitable for oily skin types as well as create fantastic conditioners that really help to protect the hair." Again, just be mindful that it can be difficult to remove and causes buildup over time since it does create a film over the skin and hair.
And if you do find that you're experiencing an allergic reaction or breakouts from this ingredient, it's probably best to avoid it and talk to your dermatologist or hairstylist.
There's also the argument that the sort of things you put on your skin should be beneficial—instead of filler or sensorial additives. This is an argument we can certainly get behind, as there are many products out there formulated without silicones that use occlusive materials with additional skin-supporting properties (things like natural oils and butters). Ultimately, the choice is yours—and we just want you to be informed about the things you put on your skin.
Here's what we know: Dimethicone can help skin and hair care products feel rich, smooth, and silky; locks moisture into the skin; and keeps knots and tangles at bay. However, its occlusive properties create a film over hair and skin, which can accumulate and cause buildup over time. And if you have an adverse reaction to it, avoid the ingredient entirely until you talk to a dermatologist.
Andrea Jordan is a beauty and lifestyle freelance writer covering topics from hair and skincare to family and home. She received her bachelor's in Magazine Journalism from Temple University and you can find her work at top publications like InStyle, PopSugar, StyleCaster, Business Insider, PureWow and OprahMag. When she's not writing, you can find Andrea tackling new recipes in the kitchen or babysitting one of her many nieces and nephews. She currently resides in New Jersey with her husband and cat, Silas.