What is polydimethylsiloxane?
Polydimethylsiloxane, also known as polydimethylsiloxane, is a substance derived from silicones. Organosilicon comes from silica, a natural compound found in sand, sandstone, granite and quartz. Manufacturers produce silicone by heating sand with carbon at high temperatures of up to 2,200°C (3,992°F). Therefore, it can be difficult to tell whether an ingredient like methane is natural or lab-created. Many cosmetics contain polydimethylsiloxane. It changes the texture of the formula, giving them a silky, velvety feel. It's also odorless, colorless, hypoallergenic, and non-comedogenic, which means it has a low risk of clogging pores.
Main points
Ingredient Type:
Emollient
Main functions:
It gives the product a silky texture, locks in moisture and protects the skin.
Who should use it:
It's safe for people of all ages and recommended for those who want to prevent dry, rough, scaly skin.
How often do you use it:
every day.
Applies to:
Moisturizers and active ingredients that cause dryness and irritation.
What products not to be used with:
Dimethicone works well with most other ingredients.
Chemical
The chemical formula of polydimethylsiloxane (also known as polydimethylsiloxane or PDMS) is CH3[Si(CH3)2O]n Si(CH3)3, where n is the number of repeating monomer units [Molecular formula =(C2H6OSi)n]. Silica (silica) is the basic material from which organosilicon is derived.
Products containing polydimethylsiloxane
This medication is used as a moisturizer to treat or prevent dry, rough, scaly, itchy skin and minor skin irritations (such as diaper rash, skin burns from radiation therapy). Emollients are substances that soften and moisturize the skin and reduce itching and flaking. Some products (e.g., zinc oxide, white petroleum jelly) are primarily designed to protect the skin from irritation (e.g., moisture).
- moisturizer
- sunscreen
- fake tanner
- Shampoo and conditioner
- Detangle products
- Head lice removal products
- Cosmetics, such as primers and foundations
- sexual lubricant
Polydimethylsiloxane also has medical uses. Some medicines for flatulence or irritable bowel syndrome may contain simethicone, which is a mixture of silicone and simethicone. This can help relieve trapped wind and bloating.
Application of polydimethylsiloxane in cosmetics
What is polydimethylsiloxane used for?
Dimethicone helps create a "slip" or "glide" feel when applying skin care products, making them easy to apply on the skin. Additionally, dimethicone coats the skin, helping to moisturize it by reducing moisture loss and providing softness and coverage to the skin—without feeling heavy.
Who should use polydimethylsiloxane?
Mild and non-comedogenic (when used to cleanse the skin), methicone is an effective moisturizing ingredient for all skin types. As a skin protectant of sorts, dimethicone is particularly useful for those whose skin needs an extra barrier to help prevent moisture loss. Dry, itchy, and rough skin may benefit from skin care products containing dimethicone.
Benefits for skin and hair
Polydimethylsiloxane has several properties that make it useful in skin and hair products, it:
- Creates a barrier: Dimethicone sits on top of the skin and hair, creating a temporary barrier. This means it provides some protection against exposure to irritants or allergens.
- Retains moisture: By forming a barrier on the skin, methicone can also reduce the amount of moisture lost from the skin.
- Improve texture: Dimethicone smoothes surfaces by filling gaps. This includes enlarged pores and fine lines. In hair products, dimethicone coats the hair cuticle, making it feel smoother. Dimethicone also gives the product a "slipperier" texture, making application easier.
- Matte finish: Primers and moisturizers for oily skin often contain dimethicone because of its matte finish. Dimethicone also helps seal in moisture without the need for heavier ingredients like oils and butters, which can be comedogenic (can clog pores).
Can I use dimethicone on my body?
Dimethicone is a gentle, effective moisturizing ingredient for face and body. It helps provide long-lasting skin smoothing effects and is ideal for areas prone to rough, dry skin, such as knees, elbows, hands and feet, and can help treat certain skin conditions such as eczema.
Is polydimethylsiloxane safe?
Experts generally agree that polydimethylsiloxane is safe for humans. Dimethicone contains large molecules, which means it is primarily found on the top of the skin or hair. A 2021 safety report confirmed that simethicone had low absorption through the skin in laboratory studies. Past animal tests have also found no evidence that polydimethylsiloxane is toxic. The U.S. Food and Drug Administration (FDA) approves dimethicone as the active ingredient. This means that a review of the product's effectiveness data found that its benefits outweighed any potential risks. Cimethicone is safe for adults to use within recommended doses, including when pregnant or breastfeeding. A 2022 article noted that researchers did not find any significant drug interactions.
Cimethicone Side Effects and Risks
Dimethicone has few known side effects or risks. However, there is evidence that it may not be as effective as other ingredients in hair care.
A 2018 study on untreated hair found that products containing vegetable oils had a greater impact on hair strength and shine than silicone-based products. This suggests that while vegetable oils can actively improve hair health, silicones have only a superficial effect on improving hair texture.
Regular use of some silicones can also cause the substance to build up in human hair. Occasionally using a clarifying shampoo, or switching to silicone-free products, may help.
There is little evidence that polydimethylsiloxane causes adverse skin reactions. In past animal studies, some animals experienced redness when researchers applied polydimethylsiloxane to their skin. However, this was temporary and quickly resolved when the researchers stopped applying it.
If any product causes the following symptoms, wash it off with a mild cleanser and stop using it:
- redness or inflammation
- itching
- swelling
- burning or stinging
If symptoms do not resolve after a few days, a person should contact their doctor or dermatologist.
Are silicones harmful to the environment?
Although silicones come from natural sources, the chemical engineering used to make them makes them harmful to the environment. Silicone adheres to skin and hair rather than sinking into it. This means that when someone removes them, they wash down the drain. From here, they enter water systems and eventually rivers and oceans. In small numbers, this won't have a significant impact. However, the widespread use of silicone cosmetics has attracted the attention of environmental scientists. According to a 2021 report, approximately 4.7 tons of certain organosilicon enter surface waters in the EU each year. The report states that these emissions mainly come from the use of flushing products. Scientists have found organosilicon in the blood of fish, birds and mammals. Some organizations say organosilicon are toxic to ecosystems and are bioaccumulative, meaning they accumulate in the environment without breaking down. The EU restricts the addition of some silicones to products, but not all. The 2021 report calls for closer monitoring of the use of silicones and their release into the environment.
Alternatives to Polydimethicone
There are alternatives to silicone-based products available. These include silicone-free shampoos, conditioners and hair products. People can look for "silicon-free" on the label or read the ingredient list. Ingredients ending in "-cone" or "-siloxane" are most likely silicones. Replacing silicones in hair care products is fairly easy because vegetable oils and butters also create a barrier around hair follicles. They retain moisture, improve shine, and, unlike silicones, strengthen hair. In skin care and other products, replacing silicones can be more difficult. Not many have the same combination of properties as polydimethylsiloxane. However, there are ingredients that can replicate one or more of its benefits, such as: Moisturizers: Moisturizers pull moisture to the skin and trap it there, adding moisture. Glycerin and hyaluronic acid are two natural humectants that help moisturize skin without the need for oil. Colloidal Oatmeal: Made from ground oatmeal, this emollient softens and smoothes the skin. The FDA approved it as a skin protectant, and a 2020 study found that 1% Colloidal Oatmeal Eczema Cream significantly improved skin's pH, barrier function, and hydration. Squalene: This is a fat molecule that can come from plants or animals. It moisturizes the skin and helps it retain moisture, but is also lightweight and non-comedogenic, similar to dimethicone. Kaolin Clay: This clay absorbs excess oil from the skin and helps it stay matte throughout the day.
generalize
Dimethicone is a type of organosiloxane, a substance created by heating sand and carbon at high temperatures. In cosmetics and personal care products, dimethicone forms a barrier on the skin or hair, reducing moisture loss and smoothing out bumps and pores. This ingredient is safe for human use and has a low likelihood of causing any adverse effects. However, when dimethicone is flushed into water systems, it can accumulate and cause harm to the environment. Silicones also may not be the most effective ingredient for strengthening hair. While they do add shine, the effect can be superficial. For those who want to avoid these substances, silicone-free alternatives are available.
Polydimethylsiloxane FAQ
Is dimethicone safe for sensitive skin?
Dimethicone is recommended for anyone with skin types who want to prevent dry, rough skin. But as with any new product, if irritation occurs, you should stop using it or see a doctor.
Does polydimethylsiloxane clog pores?
Dimethicone is a silicone, so it may clog pores. It’s best to do a patch test first to see how it will interact with your skin type.
Can I apply dimethyl silicone oil before applying makeup?
Yes. In fact, it provides a matte texture.
