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Ingredient-led beauty -

Over the past few years, beauty consumers have become more conscious of the ingredients in their favorite skincare products.

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Ingredient-led beauty -

This has led to a rising trend called "ingredient-led beauty." People choose what to buy based on the presence of certain star ingredients.

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Ingredient claims -

For example, vitamin B3, or niacinamide, is reported to brighten dull skin. Vitamin A or retinol is prescribed for anti-aging, while vitamin C is claimed to brighten and protect the skin against environmental damage.

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Ingredient claims -

One of the most popular ingredients of recent years, hyaluronic acid is claimed to deeply moisturize and plump the skin, helping to reduce wrinkles and fine lines.

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Ingredient claims -

Vitamin E is claimed to heal and soothe. The touted benefits of these (and more) ingredients involve researchers employed by beauty companies.

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Skintellectuals -

According to COSSMA, the rise in beauty product research taking place online during the pandemic led to the phenomenon of ingredient-led skincare, as "skintellectuals" spent time in seclusion, investigating claims about beauty and personal care ingredients.

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Search surge -

Online luxury retailer Net-a-Porter reported a surge in ingredient searches on its website of almost 700% between 2020-2022.

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Search surge -

It's a trend that's continuing to grow. In 2023, one of the most Googled skincare questions in the UK was "What does retinol serum do?"

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Millennials and Gen Z -

Meanwhile in the US, 61% of millennial and 48% of Gen X beauty shoppers look for specific ingredients when buying skincare products, according to a 2022 study.

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Fad, or foresight? -

It begs the question though: can the skin even absorb these ingredients and soak up the myriad of benefits promised by beauty brands?

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Fad, or foresight? -

Are we intellectualizing skincare, without knowing if these ingredients work in practice; or do they even need to be absorbed to take effect?

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Research -

As scientific research gets more advanced, it's possible to know a lot more about what passes through the skin barrier.

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Skin layers -

The skin is the largest organ in our bodies, comprising three distinct layers. The first two are most relevant when it comes to the skincare we use.

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Skin barrier -

Your skin barrier is the outermost layer of the dermis, which protects the body. Harsh environments can damage it.

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Skin barrier -

The skin barrier (or epidermis) consists of tough skin cells called corneocytes. These are bound together by mortar-like lipids. Inside the skin cells, or "bricks," keratin and natural moisturizers are found.

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The middle layer: dermis -

Ninety percent of skin's thickness comes from the middle layer. This is where you will find the skin's collagen and elastin—the proteins that keep skin plump and smooth.

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The middle layer: dermis -

Good stores of collagen and elastin help avoid wrinkles and fine lines, making this layer the holy grail of anti-aging (or not).

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Biomolecules -

The majority of biomolecules never penetrate the skin barrier, and for good reason: the skin is our body's first line of defense, designed to keep things out.

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Biomolecules -

For this reason, substances found in many moisturizers, including oils, silicones, and waxes, are too big to slip through the epidermis.

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Emollients -

What these ingredients do is remain on top of the skin, acting as emollients, aka moisturizing agents. They seal water in, helping the skin remain smooth.

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Formulations -

But certain kinds of formulations can circumvent this process. Using nanoparticles, or encasing a water-loving compound in fat or oil, can help products penetrate the skin.

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Dermis layer absorption -

To enter the dermis, an ingredient must have similar properties to the skin itself, i.e. be slightly acidic (have a pH between 4.6 and 5.5) and fat-loving (aka lipophilic), as well as having a molecular weight smaller than 500 Daltons.

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Dermis layer absorption -

However, doing this comes with its own risk. In reaching the dermis, the skincare will also be absorbed into the body's circulatory system—which cosmetic products aren't meant to do.

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Retinol -

Retinol, for instance, has been found to pass through melanocytes, the bottom-most layer of cells on the epidermis. These cells are responsible for protecting skin from harmful ultraviolet radiation.

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Retinol -

By inhibiting the growth of these cells, retinol could make users more susceptible to sun damage. This potential light sensitivity is why it's advised to use retinol at night, and apply sunscreen the morning afterwards before going outdoors.

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Parabens -

Some studies suggest parabens may affect hormone production, but more research is needed. Pregnant women might want to avoid using them as a precaution.

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Peptides -

Certain kinds of peptides have the potential to travel through the skin, but this varies widely between different types.

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Vitamin C -

Pure vitamin C is very unstable, and breaks down quickly when added to creams or serums. Some derivatives, however, can travel deeper into the skin.

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Investigation -

Sebastian Björklund, an associate professor of physical chemistry at Sweden's Malmö University, is leading a study to investigate the topic. "Not many drugs can easily cross the trans-epidermal route because the chemistry behind it is quite difficult," says Björklund.

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Science vs. marketing -

Overall, a lot of skincare walks a fine line between science and marketing. There is still a lot scientists don't know about how much skincare is absorbed, and what the risks are. Tread carefully!

Sources: (BBC Future) (COSSMA) (Euromonitor) (Healthline)

See also: Common skincare mistakes you're probably making

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