Skincare Absorption Pt. 1: Skincare is an important part of our daily routines. But have you ever wondered where all that skincare goes? Does it penetrate our skin and enter our bloodstream? Let us find out what science has to say about skin penetration.
Wanting to look and feel our best is not a new concept. In fact, people have been applying cosmetics to their skin for at least 10,000 years. Historically, humans have used cosmetics to lighten or darken their skin, enhance certain features, distinguish between social classes, and provide important ceremonial rites. It seems that applying substances to our skin is a natural part of human existence. It maybe to alter our appearances or to provide relief from pain and irritation.
We spend billions of dollars every year on products for our skin. Advertising of skincare do not solely target women any longer. It is no secret that we put a lot of things on our skin–sunscreen, lotion, anti-aging creams, makeup, and more. Sometimes, those substances protect our skin and help it heal. Other times, those substances are neutral–they neither help nor harm. Occasionally, people have been harmed or even killed by substances they put on their skin, as was the case with lead-based makeup. Even clothing has been harmful in the past because people did not understand skin penetration. Many women suffered when dresses dyed green with arsenic were all the rage, for example. Clearly, it is important to understand what our skin can absorb.
Understanding your skin
Your skin is made up of layers. Some skin products, like sunscreen, work on the surface of the skin, while others need to reach deeper layers of the skin to be effective. That is the case for antioxidants and products that work by reducing fat. It is important that the products we use reach only the intended layer of skin and not reach our bloodstream. That is a challenge continually faced by the scientists who develop cosmetics. However, now, we thankfully have regulatory laws preventing high concentrations of lead in our makeup and arsenic in our clothing today.
Despite our long history of skincare, we only started to understand skin penetration in the last 100 years. That knowledge is vitally important, particularly for products targeting deeper layers of skin. In the past, it was thought that the stratum corneum (outermost layer – figure 1) was the only barrier that prevented chemicals from entering the skin. However, we now know that deeper layers, like the viable epidermis and dermis also play a role in absorbing small molecules.
How do cosmetics get absorbed by the skin?
Our skin is our largest organ, and it plays an important role in protecting our inner organs and keeping contaminates out of them. As such, it can be difficult to get cosmetics to penetrate the skin deeply enough to work. In order to accomplish that goal, skin penetration enhancers are added. These can be chemical, enzymatic, or vesicular.
Scientists have found that several important factors impact the ability of substances to penetrate our skin. For optimal penetration, substances need to have a low molecular weight and have good solubility in both water and lipids, because our skin contains both water and fat. The choice of solvents, emulsifiers, and formula compositions are also important. Finally, it is crucial that the product does not accumulate in the stratum corneum or bind with it. That is especially important for coloured cosmetics.
Science behind safety in skincare
Every now and then, a story hits the news about the safety of our cosmetics. It is alarming to hear that something dangerous from the products we have applied could penetrate our skin.
In 2004, that happened with parabens. A study found parabens in 18 of 20 breast cancer tissue samples that were tested. The media reported this saying that parabens contributed to breast cancer growth and consumers began to avoid products that contained them. Notably, any chemical in the bloodstream likely exist in breast cancer tumours because there is a large blood supply to them. However, a direct link between parabens and development of tumour could not be determined with conclusive evidence. In contrast, studies show that the the body metabolized and excreted parabens without causing harm.
Triclosan was developed as a surgical scrub for hospitals and has also been used as a pesticide. It is in many products, including cosmetics and toothpaste. Studies have found that exposure to triclosan over time causes fibrosis and cancer in mice and that it can interfere with hormones and reduce our ability to fight bacteria. However, when used correctly, it has been proven to treat gingivitis and bleeding gums. We need further studies to gain a more complete understanding of any dangers posed by triclosan, so consumers may want to choose products that do not contain it until additional research is published.
Formaldehyde, Phthalates & Lead:
Substances like formaldehyde, phthalates, lead, and other metals may be harmful in large concentrations but are safer in small amounts. Formaldehyde occurs naturally in our environment, and it is in cosmetics in very small amounts. However, research has shown that some people may experience skin irritation even from the tiny amounts of formaldehyde allowed in cosmetics.
Some studies have found that pthalates interfere with the balance of hormones in our bodies, and other studies have found a link between phthalates and type 2 diabetes. In response, several governing authorities have banned specific types of phthalates from use.
We all know that lead is dangerous, so why is it in products we apply to our skin? Lead and other metals naturally occur in our environment, so they end up in a lot of the products we use. They are not specifically added to cosmetics. Studies have found that you will take in more lead from drinking water than wearing makeup. The scientific consensus is that the amount of metals in cosmetics falls within a safe range, but more research needs to be done, particularly for chromium.
How we, at Au Natural Skinfood can help to keep you safe
Understanding our skin is important when choosing what products, we want to apply to it. While it is great that we have regulatory authorities to help keep harmful chemicals out of our products, the science is always evolving, and consumers should be able to make informed decisions. Look for brands that are transparent about their ingredients, can back up their claims with science and that are natural practising clean beauty.
At Au Natural Skinfood we strongly believe that if we can strengthen the skins natural barrier function to be the best that it can be, then we can use our skins own defence system to fight environmental damage and external pollutants. Manuka honey has a large molecular structure and we do not use nano technology, meaning that our Au Natural products cannot penetrate the dermal layers.
We suggest supporting your skin with our Hair.Skin.Nails. collagen powder, it is a nutricosmetic which means that we feed your skin with the active ingredients that it needs from the inside, they transit through your digestive tract, are absorbed into your intestines and then circulate to cells that need them, fighting free radicals and in a nutshell your hair, skin and nails will be stronger, will have the nutrients to naturally repair themselves and look healthier. Our collagen powder is designed to support our skincare products to rebuild your skin in a hand holding approach.
Au Natural is committed to helping you create new healthy skin habits. No nasties, no nutrient-depleted fillers, just Au Natural Skinfood.
Tracy – Founder
- Skin Absorption and Natural Skincare Products: With regards to molecule size and depth of absorption e.g. https://www.essentially-yours.co.uk/blog/why-we-are-different-to-any-other-skincare-brand-/.
- The chemistry of cosmetics by Dr. Oliver Jones, & Prof. Ben Selinger, AM, at https://www.science.org.au/curious/people-medicine/chemistry-cosmetics.
- Milady Skin care and the cosmetic ingredients dictionary 4th edn (2014), by M. Varinia Michalun & Joseph C. Dinardo.