Last updated: Friday July 12th 2019

They’ve been around for over sixty years, and their usage is still increasing. When it comes to beauty products, silicones are everywhere. Shampoos, conditioners, styling products, sunscreens, primers, foundations, lipsticks, mascaras and more all contain them.

So what exactly are silicones? And why have they become so ubiquitous in the beauty world?

Silicones are made by synthesising the element silicon with oxygen and other elements, such as carbon and hydrogen. Because silicon binds readily with oxygen, it is rarely found in a pure state in nature, and most commonly exists as silicon dioxide or silica. Silica is found in high abundance in quartz (sand). And, sure enough, it is sand that is frequently used to make silicones.

As for their enduring popularity, silicones have a range of properties that make them perfect additions to beauty formulas. They smooth and improve product application, increasing ‘slip’ and spreading; protect against water loss; provide water resistance and durability; help to repair skin or hair damage; add gloss; improve the appearance of lines and wrinkles; create breathable barriers; and can act as delivery systems for other ingredients.

To utilise these diverse qualities, silicones come in different forms, including fluids, waxes, polyethers and elastomers. One of the most commonly used is cyclomethicone, as its rapid rate of evaporation makes it a useful carrier for active ingredients that are designed to be absorbed by the skin. Cyclomethicone has come under regulatory scrutiny recently, however there are alternatives available in the form of short-chained dimethicones. Dimethicone and dimethicone copolyol work by forming a breathable film over skin which then enables other ingredients to stay on the surface. They are frequently used in BB and CC creams, where they help to maintain even pigment tone.
Crosslinked silicones, otherwise known as elastomers, are among the newest types of silicone on the market and are typically found in anti-aging products. They create a ‘soft-focus’ blurring effect that helps to conceal imperfections, lines and wrinkles by reflecting and diffusing light. Silicone elastomers have a distinctive dry, silky feel on the skin and also act to absorb excess oil, mattifying and evening out skin tone.

In sun care products, silicones add water-resistance, providing protection for longer periods while avoiding the stickiness associated with many organic sunscreens. Acrylates siloxanes are particularly suitable to provide these properties; They play a similar role in cosmetics, making mascaras waterproof and long-lasting, and giving additional staying power to lipsticks, eyeliners, foundations, eyeshadows and blushers, as well as enabling them to be applied more smoothly.

And silicones aren’t just good for use in skin products– they have long been used in hair formulations where they feature in shampoos, conditioners and styling products. They have the ability to repair the surface of damaged hair, coating it to make it feel softer and smoother, as well as imparting extra shine. In addition, resin blends have been shown to be excellent de-frizzing agents. Silicones also stay in place to help strengthen hair and safeguard against further damage and humidity.

Although they cannot be termed ‘natural’, they are derived from natural ingredients and are biologically inert and degradable. They are also suitable for vegan products and are not derived from palm oil. They often perform better than natural oils and waxes too. For example, the smaller molecule size of vegetable, nut and seed oils mean they can penetrate the skin and clog pores, while silicone molecules are too large to be absorbed, making them non-comedogenic. In fact, The American Academy of Dermatology suggests silicone-based cosmetics might help those suffering from cystic acne and rosacea.

When you consider their many benefits, it’s no wonder silicones appear on the labels of so many beauty products, and that they’ve been doing so for so long. Not bad for something that started life on a beach…