Silicones are a tricky topic. They are widely used in cosmetics, and you will find ‘cones on many a cosmetic label, both in high-end and drugstore products. However, you will also have likely seen an increasing number of products advertised as ‘free of silicones’. Does that mean that silicones are harmful and should be avoided? If you have already done your research, you will know that the truth is somewhat complicated and confusing. Regardless, we are here to separate some facts from fiction in order to help us make better choices for ourselves.
What are silicones in beauty products?
To begin with, what are silicones? Silicones are synthetic polymers made up of silicon, oxygen, and combinations of other elements. They’re easy to spot on a product label because their names end in in -cone or -siloxane; such as Amodimethicone, Cyclopentasiloxane and Dimethicone (the most common beauty ‘cones).
They are often included in cosmetic formulations to make our products feel good: smooth, fluid and spreadable. They add softness and a velvety yet matt texture to serums and moisturizers, and act as an occlusive to keep moisture locked into our skin. They fill in pores and fine lines and have a reflective quality which adds a glow. They add shine and luminosity to our hair, and help to detangle and reduce breakage. All wonderful things.
This all sounds great so far. So, are silicones actually bad?
There is some misunderstanding here, and it depends on what your expectations are. In skincare products, silicones form a firm yet breathable barrier over the skin. Their molecular structure is large with wide spaces in between, allowing them to form a long-wearing, waterproof film that protects against moisture loss yet doesn’t feel heavy or greasy. It is this same property that gives them that velvety smooth feel and makes them great primer ingredients. This molecular structure is also what makes them non-comedogenic – they are unable to penetrate the skin, sitting on top of it instead.
However, these properties are also why they fall under criticism. Silicones add a silky texture to skincare products which make them feel as if they’re working and making improvements to the skin, however it is a temporary and superficial effect. In reality, silicones add no benefits to the skin’s general texture or condition. While this doesn’t cause any harm, it could be misleading to a consumer who isn’t necessarily aware of the effects that silicones have in their products.
Another reason why this property has given silicones a bad name is because this barrier not only locks in moisture, it can also lock in excess oils, dead skin cells and bacteria onto the skin’s surface. This can lead to a dull appearance, congestion and breakouts. So, unless you are diligently double-cleansing you may start to experience these side-effects with regular use of silicone-heavy products. However, everyone’s skin has a different level of tolerance so there is no clear-cut limit, and again, not all silicones are made equal.
Silicones in haircare products
When it comes to hair products, silicones coat the hair strands and create a wonderful slip which detangles and reduces frizz. The downside of this is that product build-up can accumulate if they are used frequently, which over time can weigh the hair down and give it a dull appearance. This can also mean that the sealed strands are prevented from absorbing oxygen and other nutrients, weakening it and leading to breakage.
On the other hand, silicones are often what create a smooth and manageable finish, reducing the likelihood of breakage. Additionally, lightweight silicones (such as PEG-7 dimethicone, dimethicone copolyol, cyclomethicone, or cyclopentasiloxane) are less likely to lead to build-up in the hair and on the scalp, and with the occasional use of clarifying shampoo, moderate use of hair products formulated with silicones is unlikely to do any damage.
Are silicones bad for your health or the environment?
For the most part, silicones are widely used in medicine due to their stable, non-reactive and non-irritating properties which overall make them very safe for use in cosmetics.
There are concerns that some types of cyclic silicones, including cyclotetrasiloxane (D4), cyclopentasiloxane (D5), cyclohexasiloxane (D6), and cyclomethicone, may act as endocrine-disruptors, essentially interfering with hormonal and reproductive systems in certain doses, although its not clear exactly what those are. Additionally, in order to be harmful, these compounds would have to be absorbed into the body, which they typically aren’t as they are included in formulations to promote fast evaporation. Overall, it has been determined that formulations with low concentrations of these silicones are likely to be harmless. Linear silicones, such as dimethicone, have a larger, more stable molecular structure and are also known to be harmless.
When it comes to environmental concerns, there is an equal amount of misunderstanding. Silicones are derived from the naturally-occurring substance silica (sand), which is abundant and sustainable. They are also vegan and cruelty-free, as they are not derived from animal sources.However, once the silicones typically used in cosmetics are formed, many are not biodegradable. There are concerns that over time, some silicones used in rinse-off products may be bio-accumulative (i.e. build up) and be potentially toxic in aquatic environments, although there is no clear evidence to substantiate this. Furthermore, these particular silicones (D4, D5, and D6 as above), are not usually used in rinse-off formulations so the overall risk is low.
What the use of silicones really comes down to is preference. There is no evidence that silicones are actually harmful to personal health and as long as you are cleansing – both your hair and skin – properly, you are unlikely to be at any risk. What silicones don’t do is add any actual benefits and this can sometimes disguise poor performance, so just be sure to read the label and understand what is in your beauty products.