There are numerous forms of silicones used in cosmetic products, particularly leave-on skincare products and all manner of hair-care products. Common forms of silicone are cyclopentasiloxane and cyclohexasiloxane; other forms include various types of dimethicone and phenyl trimethicone.
Claims that silicones in any form cause or worsen skin concerns have not been substantiated in published research, nor have reports that silicones are sensitizing to or “suffocate” skin. Almost all of these claims are either myths or based on anecdotal evidence, which isn’t the best way to determine the safety or efficacy of any cosmetic ingredient. How do we know that silicones don’t suffocate skin? Because of their molecular properties they are at the same time porous and resistant to air. Think of silicones in a skincare formula like the covering of a tea bag. When you steep the tea bag in water the tea and all of its antioxidant properties are released.
Silicones remain on the surface of your skin and the other ingredients it’s mixed with “steep” through. All ingredients must be suspended in some base formula; some of the ingredients remain on the surface, some are absorbed. The intent is for the “actives” to get through.
What is Dimethicone?
Dimethicone is what the chemists like to call a silicon-based polymer—”polymer” meaning it’s a large molecule made up of several smaller units bonded together. Simply put, it’s a silicon oil, man-made in the laboratory and used in personal care products as an anti-foaming agent, skin protectant, and skin and hair conditioner.
Manufacturers like it because it makes products easily spreadable, so you get that feeling of the lotion or cream gliding over your skin. Dimethicone also helps form a protective barrier on the skin, and can fill in the fine lines and wrinkles on the face, which is why it’s often used in makeup primers.
Is Dimethicone Safe?
The FDA has approved the use of dimethicone as a skin protectant ingredient in over-the-counter products, and the Cosmetic Ingredient Review (CIR) panel has assessed it as safe to use in personal care products. Some studies have found it to soothe and help improve chronic hand dermatitis, and to help reduce inflammation and irritation. The Skin Deep Database also lists it has have a low hazard risk.
For me, though, this is not a good ingredient to be using in your daily skin care. Like petroleum products, silicone oils can actually make dry skin worse over time. Instead of sinking into your skin and nourishing it from the inside out, like healthy ingredients do, it forms a sort of plastic-like barrier on the outside of skin.
Why Dimethicone is Bad for Your Skin
That artificial coating on the outside of skin causes several issues:
It traps everything under it—including bacteria, sebum, and impurities—which could lead to increased breakouts and blackheads
The coating action actually prevents the skin from performing its normal activities—like sweating, temperature regulating, sloughing off dead skin cells, etc.
Prolonged exposure to dimethicone can actually increase skin irritation, due to the coating property and because dimethicone is listed as a possible skin and eye irritant
Those with sensitive or reactive skin are at risk of an allergic reaction to dimethicone
On top of all this, dimethicone is a non-biodegradable chemical—bad for the environment
I also believe that using these types of ingredients on your skin can actually exacerbate skin aging. Why?
You’re inhibiting skin’s natural processes
You’re creating a dependency on the coating product, disrupting the skin’s own hydrating processes, which in the end increases dryness, making fine lines and wrinkles more noticeable
The coating properties may increase breakouts, particularly if you’re susceptible to acne, which will lead to scars and older-looking skin
You’re doing nothing to boost the health and vitality of the skin, thus letting aging take its toll
Much better to use nourishing ingredients that help keep your skin hydrated naturally! (Speaking of, check out my new skin care line here!)
To avoid this ingredient, stay away from all dimethicone and similar ingredients like cyclomethicone, dimethiconol, and phenyl trimethicone.
Based on their mechanism of action, topical sunscreens can be broadly classified into two groups, chemical absorbers and physical blockers. Chemical absorbers work by absorbing ultraviolet (UV) radiation and can be further differentiated by the type of radiation they absorb, UVA or UVB, or both UVA and UVB. Physical blockers work by reflecting or scattering the UV radiation.
Sunscreen agents are used to prevent sunburn. Limiting your exposure to the sun and using sunscreen agents when in the sun may help prevent early wrinkling of the skin and skin cancer. There are two kinds of sunscreen agents: chemical and physical. Chemical sunscreen agents protect you from the sun by absorbing the ultraviolet (UV) and visible sun rays, while physical sunscreen agents reflect, scatter, absorb, or block these rays.
Sunscreen agents often contain more than one ingredient. For example, products may contain one ingredient that provides protection against the ultraviolet A (UVA) sun rays and another ingredient that protects you from the ultraviolet B (UVB) sun rays, which are more likely to cause sunburn than the UVA sun rays. Ideally, coverage should include protection against both UVA and UVB sun rays.
The sun protection factor (SPF) that you find on the label of these products tells you the minimum amount of UVB sunlight that is needed with that product to produce redness on sunscreen-protected skin as compared with unprotected skin. Sunscreen products with high SPFs will provide more protection against the sun.
Sunscreen products are available with and without your doctor’s prescription. If you are using this medicine without a prescription, carefully read and follow any precautions on the label.
This product is available in the following dosage forms:
Studies have shown that UVA impairs the antigen presenting cell (APC) activity of the epidermal cells and thereby causes immune suppression, thus contributing to the growth of skin cancer. Sunscreening agents have shown to provide significant protection against epidermal APC activity induced by high UVA dose.6 Mutation occurring in human melanocyte due to damage caused to DNA by UVA radiation is one of the proposed reasons.7 In summary, UVA radiation can cause nuclear and mitochondrial DNA damage, gene mutations and skin cancer, dysregulation of enzymatic chain reactions, immune suppression, lipid peroxidation (membrane damage), and photoallergic and phototoxic effects.
To find a list of what chemicals are used in sunscreen agents, please click HERE.
Avobenzone, Mexoryl, Oxybenzone, Benzophenone:
Sunscreens commonly include ingredients that act as “penetration enhancers” and help the product adhere to skin. As a result, many sunscreen chemicals are absorbed into the body and can be measured in blood, breast milk and urine samples.
The most common sunscreens on the market contain chemical filters. These products typically include a combination of two to six of these active ingredients: oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate.
The Centers for Disease Control and Prevention has detected oxybenzone in more than 96 percent of the American population, based on a representative sampling of children and adults (Calafat 2008). Participants who reported using sunscreen have higher oxybenzone exposures (Zamoiski 2015). Oxybenzone can cause allergic skin reactions and may disrupt hormones (Rodriguez 2006, Krause 2012).
Titanium dioxide is a naturally occurring mineral that is mined from the earth then further processed and purified for use in consumer products. Also known as titanium (IV) oxide or titania, it is the naturally occurring compound comprised of the metal titanium and oxygen. Titanium dioxide is safely used in many products from paint and food to drugs and cosmetics. It also plays a critical role in some sunscreen products as a way to protect skin from the sun’s harmful ultraviolet radiation.
Titanium dioxide is an important active ingredient used in some sunscreen products. Sunscreens are regulated by the U.S. Food and Drug Administration (FDA) as over-the-counter (OTC) drugs. As such, they must be shown to be safe and effective and must comply with all other requirements listed in the FDA’s OTC sunscreen monograph. Individual sunscreen active ingredients are reviewed by FDA and only those that are on FDA’s monograph approved list may be used in sunscreen products marketed in the U.S.
Cancer (Inhalation Exposure Only)
The International Agency for Research on Cancer designates titanium dioxide as a carcinogen, largely due to studies in animals that have found increased lung cancers due to inhalation exposure. Evidence to date does not demonstrate increased cancers when exposures occur through the skin or swallowed. Human studies, mostly occupational studies TiO2 inhalation, have demonstrated mixed findings.
Nano Titanium Dioxide
The prevailing data indicate that nanoized TiO2 does not pose hazards that are unique from those of larger particle TiO2. One concern about nanomaterials is possible skin penetration. The literature investigating this suggests that because nanoized TiO2 forms clusters, it does not penetrate the skin, particularly to the deeper (dermal) layers of skin. In response to concerns that nano TiO2 might more readily penetrate damaged skin, researchers applied nano-based sunsreens to pigs ears that had been sunburnt. TiO2 did not reach the deeper levels of the skin in the sunburnt tissue. Nevertheless, toxicological testing of nanomaterials needs to take into account the effects on particle size on the ways that dose is estimated because smaller particles will have greater surface area by volume.
Inhalation of nano Titanium dioxide is of concern, given the cancer concerns for TiO2 of any size. One study assessed the likely inhalation exposure of TiO2 from cosmetic powders and found that most nano particles of TiO2 were inhaled either as clusters of nanoparticles (agglomerates) or attached to larger TiO2 particles. This meant the particles were inhaled into the upper parts of the lungs but did not reach the alveoli (the part of the lungs where oxygen is exchanged). Many toxicological studies of nanoized Titanium Dioxide inhalation assume alveoli exposure, so studies should explore effects on the upper parts of the lungs.
Paula’s Choice – Silicone
Dr Frank Lipman – The Truth Behind The Common Cosmetics Ingredient, Dimethicone
DermNet New Zealand – Classification of sunscreens
Mayo Clinic – Sunscreen Agent (Topical Application Route)
NCBI – Sunscreening Agents
Just About Skin – List of Sunscreen Agents (UV Filters) in the U.S.
EWG – The Trouble With Oxybenzone and Other Sunscreen Chemicals
Cosmetics Info – Titanium Dioxide
Campaign for Safe Cosmetics – Titanium Dioxide