Ingredient Spotlight: Cyclopentasiloxane

Ingredients, Skin Care

Cyclopentasiloxane is a silicone. Yes, I’m holding a cube of silicone and standing in front of a periodic table. I’m just cool like that.

Circa 1998, my beauty routine probably consisted of something like a Noxzema cleanser (conditioner), 10-Oh-6 Toner (solvent), and the old Clinique Dramatically Different Moisturizing Lotion (hydrator). That’s because, well, I was young and just learning about skin care. More importantly, this was because there were essentially two types of ingredients before the 2000’s: drying and non-drying.

Enter silicones. Found in beauty products with names like cyclopentasiloxane, cyclohexasiloxane, dimethicone, and phenyl trimethicone, silicones are quadruple threats, acting as silky moisturizers, conditioners, solvents, and delivery agents for other skin care ingredients. It wouldn’t be possible to have a makeup primer or a BB/CC cream without silicones; the entire concept of having a product simulataneously hydrate, protect, and prime the skin for additional product is all attributable to silicones.

How Do Silicones Work?

Silicones have a specific set of chemical properties, including a large size and significant spacing between each molecule, that enable them to form a molecular lattice on the skin.

This lattice will allow the silicones to set on the surface of your skin as a moisturizer and conditioner, while enabling ingredients like antioxidants, AHAs, fatty acids, and plant extracts to reach the surface of your skin. While beneficial ingredients will eventually traverse through heavier products, like the new skin care oils and older products with petrolatum and mineral oil bases, it is a shorter process with silicones, so the effects happen faster, and with less occlusion (suffocating) of the skin. On the other hand, beneficial ingredients reach the skin even faster when they are embedded in a solvent like alcohol, but low-molecular weight alcohols do not have hydrating properties for the skin. So silicones can provide a happy medium that is suitable for just about all skin types.

What are the Best Silicones for the Skin?

It depends on your skin type. Those with dry skin would probably prefer products with dimethicone, which is a heavier silicone that protects and hydrates the skin a little better than the others. On the other hand, those with oily skin would benefit most from products with cyclopentasiloxane or cyclohexasiloxane, which are not only lighter and silkier, but also are the most common to find in products.  If you have a mixed skin type – oily T-zone, dry patches on your cheeks, etc. – then any silicone will probably work. This is because the difference in chemical properties between dimethicone and cyclopentasiloxane/cyclohexasiloxane are fairly minimal when imparted to the skin. In general, you’ll notice more slip with lighter silicones like cyclopentasiloxane and cyclohexasiloxane and more hydration with dimethicone.

What are the Best Silicone-Containing Products for the Skin?

Some of the best silicone-containing products for the skin are:

Hourglass Mineral Veil Primer – Amazing for Oily Skin! ($69.99,

Primers used to be like being in the “cool” clique in high school: if you have oily, acne-prone skin, it’s harder to be included. Thankfully, Hourglass Mineral Veil Primer gets with the program, with lightweight silicones and alumina, one of the most absorbent materials on earth (GlobalSpec).  Alumina is so absorbent that it is used as a desiccant (drying agent) commercially to dry out gases.  If it can do that to 10,000 gallon jugs of water, imagine what it can do for your skin!

I’m also a fan of Hourglass Mineral Veil Primer because it contains two forms of physical sunscreen, titanium oxide and zinc oxide.  Unlike chemical sunscreens, which allow UV light to hit your skin and then transform it into another form of energy that won’t hurt your skin, physical sunscreens provide a barrier so UV light doesn’t hit your skin from the start. Zinc oxide blocks a significantly longer length of rays than titanium oxide in the aging UVA spectrum, so I’m happy this primer contains more zinc oxide than titanium oxide (Skin Pharmacology and Physiology, 2005).

Ingredients in Hourglass Mineral Veil Primer:  Titanium Dioxide: (2.45%).  Zinc Oxide: (4.20%).  Cyclopentasiloxane, Isododecane, Polysilicone-11, Polymethylsilsesquioxane, Hexyl Laurate, Peg-10 Dimethicone, Polyglyceryl-4 Isosterate, Stearic Acid, Alumina.

Smashbox Photo Finish Foundation Primer – Amazing for Dry to Normal Skin! ($33.95,

I can actually remember the first time I was introduced to Smashbox Photo Finish Foundation Primer. I was in college, and one of my friends wanted to go to Ulta and pick up some makeup.

“What’s this?” I asked, picking up the box. It was all sleek, black packaging, and clear, minimalist labeling. I was intrigued.

“Ohmigod, it’s a primer,” my friend replied. “You don’t use a primer?” You would’ve thought I told her I didn’t know who the president was or something.

So I tried Smashbox Photo Finish Foundation Primer on my cheek, and I was dazzled by how smooth my cheek felt to the touch. It was really something.

The vain side of me immediately wanted to start using it, but the scientific side of me wanted to do more research first. Hence how I came to know about dimethicone and silicones in general, and also how I now will not leave the house without using a primer or our vitamin CE serum as a primer. Truth. Which brings me to this, actually:

FutureDerm CE Caffeic 16+2 Silk Serum: Great for All Skin Types ($89.00,

So I designed FutureDerm Ce Caffeic 16+2 Silk Serum to be a 2-in-1 treatment serum and primer for the skin, designed for use prior to moisturizer and/or sunscreen. Since 15% vitamin C and 2% vitamin E have been shown in independent scientific studies to boost UVA/UVB protection by up to 400% (Acta Dermato Venerelogica, 1996), use of these synergistic vitamins each morning under a moisturizer with sunscreen and/or a sunscreen is excellent indeed. Plus, the lightweight silicone mix in our FutureDerm Ce Caffeic 16+2 Silk Serum is designed to allow your skin to breathe and beneficial ingredients to reach your skin.

The best part of our FutureDerm Ce Caffeic 16+2 Silk Serum is how we use the silicones: the vitamin C in FutureDerm Ce Caffeic 16+2 Silk Serum is microencapsulated within silicones to ensure a slow, sustained release of vitamin C for approximately 8 hours. This simultaneously makes the vitamin C in our product more effective, and better for sensitive skin types. [Read more: FutureDerm to the Rescue: A Vitamin C for Sensitive Skin Types on My Beauty Bunny] The vitamin C contained in the product also won’t readily degrade upon exposure to light, air, or heat, unlike the vast majority of our competitors’ products. So you won’t ever see FutureDerm Ce Caffeic 16+2 Silk Serum turn yellow, orange, or have a funky smell like a lot of other vitamin C serums out there do after repeated usages over time. It’s really great, and it of course comes with a money back guarantee!

Are Silicones Safe and Non-Comedogenic?

The answer to both is yes. Silicones have both water-binding and water-resistant molecules in their composition. So when silicones lay atop the skin, they are able to bind to the skin and provide a protective covering, and simultaneously bind to moisture in the air and hold it to the skin. Because silicones generally will form a base that is non-viscous (sticky), beneficial ingredients are also usually able to easily traverse the distance through the silicones and reach your skin in a reasonable amount of time.

Silicones also have wide spaces between each molecule. This forms a molecular lattice that allows for air to get through, in what some would say allows your skin to “breathe”. The only issue? Don’t get silicones in your eyes: Cyclopentasiloxane may cause mild skin and eye irritation, according to the ingredient’s material safety data sheet. Some are concerned that silicones can be absorbed into the lowest layer of the skin, the dermis, but silicones have not been shown even then to traverse the blood vessels and get into the bloodstream. Silicones are, however, effective in allowing other beneficial ingredients to traverse through them and into the skin.

Bottom Line

Cyclopentasiloxane is a silicone that allows the skin to breathe, while simultaneously hydrating the skin and delivering beneficial ingredients to it. Cyclopentasiloxane is a more lightweight silicone than dimethicone, so think of cyclopentasiloxane if you have normal to oily skin, or dry skin that is otherwise well-managed. In terms of recommendations, I suggest trying Smashbox Photo Finish Foundation Primer if you have dry skin, Hourglass Mineral Veil Primer if you have oily skin, and our FutureDerm Ce Caffeic 16+2 Silk Serum if you would be interested in having a 2-in-1 treatment serum and primer.

What are your thoughts on cyclopentasiloxane? Let me know in comments below!
Looking for the best skin care? FutureDerm is committed to having its customers find — and create — the best skin care for their individual skin type, concern, and based on your ingredient preferences. Learn more by visiting the FutureDerm shop!

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