What is a Serum and Why is it the Most Important Skincare Step
When skin care became a regular part of your daily routine, you probably learned to adhere to three general steps: cleanse, tone and moisturize. But these days, the almighty face serum has secured itself as an essential skincare staple, particularly for those seeking to take preventative and proactive measures against the telltale signs of aging: fine lines, wrinkles, discoloration, sagging and dryness, to name a few.
Typically lighter and more fluid in texture than a moisturizer, serums have become an indispensable addition to anti-aging rituals thanks to their high-performing actives. For this reason, serums are an excellent way to strengthen and supplement your overall skincare routine so it’s more comprehensive and tailored to your unique needs.
If you’re not yet convinced, here are the top reasons why using an anti-aging face serum is important and the best ingredients to look out for.
Serums offer higher concentrations of actives than moisturizers and creams
Because they’re usually designed to treat specific conditions, serums contain a higher ratio of actives, high-performance—oftentimes clinically proven or vastly studied—ingredients that typically serve to improve a condition like fine lines, wrinkles, dehydration, sagging or hyperpigmentation. This means you see visible transformation more dramatically and more quickly than using your run-of-the-mill cream.
Serums enable you to target specific skin conditions
Think of it this way: a standard moisturizer’s primary role is to hydrate; it’s secondary role is to treat with additional ingredients, like protective antioxidants. A serum, on the other hand, prioritizes treating skin conditions, whether it’s anti-aging, brightening, hydrating or alleviating dullness.
Even better? Say you want to address fine lines and hyperpigmentation. You can mix and match your serums depending on what your skin needs at any time, whether you want to switch them up from day to night, day to day, between seasons or during and after a vacation.
Generally speaking, you can layer two to three serums as long as you wait at least a minute or two for each to absorb into the skin. However, make sure you do your research and avoid combining actives that don’t mesh well together, as it will cause irritation or damage. Some ingredient pairings you should keep an eye out for include:
Retinol and alpha hydroxy acids
Certain forms of Vitamin C, such as L-ascorbic acid, have been shown to cause irritation when mixed with retinol or alpha hydroxy acids, or become less effective
Retinol and benzoyl peroxide
Note that these combinations aren’t a bad mix 100% of the time—so it’s important you do your research and reach out to the brand for more information.
Serums penetrate deeper into the skin
You’ll notice that most serums are more thin, watery and lightweight in texture. There’s a term used by cosmetic chemists called “viscosity” which, in simple terms, describes the thickness of a formula. Despite the prevalent myth that your skin “drinks up” everything you apply on it, skincare ingredients don’t always have an easy time getting through to work their magic. In fact, when a solution is too thick, the vast majority of it can simply sit on top of skin, essentially blocking other ingredients from entering. This is why serums are typically lighter and water-based—the formula contain smaller molecules that can actually penetrate skin and go deeper.
A note to bear in mind: More and more, brands are developing oil-based skincare products that are labeled as “serums.” Oils have a larger molecular weight, so it should be the final step of your skincare regimen to prevent it from impeding other ingredients from soaking through. Do not apply oils immediately after cleansing and toning.
Serums contain fewer bad ingredients
Because serums are potent fixer-uppers, they are concentrated with actives and complementary ingredients that work in synergy to boost performance or create a pleasant, usable texture. This means serums tend to have fewer ingredients that do not serve a function. Standard moisturizers and creams, on the other hand, are often formulated with controversial ingredients like silicones, thickeners and parabens, which can cause irritation for some. The downside of this is serums tend to expire more quickly, but that means you’re reaping the benefits of the actives at their most potent state.
Most Popular Face Serum Ingredients
When looking for the best face serum for you, you’re likely to run into these ingredients. Take a moment to learn about each and how they can help your unique skincare concerns:
Bioengineered epidermal growth factors (EGF)
All our bodies contain growth factors, which are specialized “signal molecules” that communicate with other cells and “tell” them to multiply or repair themselves. The growth factors that exist in your skin are called epidermal growth factors—and they diminish with age. Studies have shown that topical application of bioengineered EGFs (EGFs from sources like barley that simulate those made in human skin) can dramatically reduce the appearance of fine lines and wrinkles and skin texture.
Vitamin B3, also called niacinamide in its active form, is one of the eight B vitamins. When taken internally, these vitamins are essential for good health. Vitamin B3 also has some scientifically proven benefits for your skin. A 2005 study showed that vitamin B3 can improve the appearance of skin aging, including improving wrinkles, yellowing and skin elasticity. Another study from the State University of New York College of Medicine demonstrated vitamin B3’s anti-inflammatory effect on acne.
Vitamin C is a strong antioxidant that’s often used for its anti-aging properties. There are several types of vitamin C used in skin care, some of the most common of which are L-ascorbic acid and tetrahexyldecyl ascorbate. L-ascorbic acid is water-soluble, while tetrahexyldecyl ascorbate is soluble in lipids, or fats.
In a 2012 study, Chinese volunteers applied a solution of L-ascorbic acid to half of their faces for two weeks. Researchers found that 75 percent of volunteers were happy with the results, noting that L-ascorbic acid improved the appearance of fine lines and skin roughness. Another split-face study by Dermatology Associates of San Diego County found that applying a solution of L-ascorbic acid and tetrahexyldecyl ascorbate to half of their faces drastically reduced wrinkles after 12 weeks.
Vitamin E has been used in skin care for many years. It is a powerful plant-based antioxidant that is necessary for healthy skin. There are several benefits of applying vitamin E topically. Research from Northwestern University School of Medicine suggests vitamin E can protect the skin from harmful UV rays. Research from the University of California School of Medicine also showed that vitamin E, when combined with vitamin C, had a photoprotective effect on the skin.
Ferulic acid is a strong antioxidant found in plant sources. A 2008 study showed that ferulic acid, when combined with vitamin C and phloretin, protected skin from the UV rays that can cause damage such as photoaging and skin cancer. Another study from Duke University found that ferulic acid also protected skin when combined with vitamins C and E. Ferulic acid improved the chemical stability of the other two vitamins.
A study conducted in China also found that a mixture of ferulic acid, ginkgo biloba, lipohydroxyacid (LHA), niacinamide and thermal spring water effectively whitened skin for sufferers of hyperpigmentation due to sun damage.
A synthetic form of Vitamin A called retinol has long been used in skincare for its anti-aging properties. In 2007, the University of Michigan Medical School conducted a study on the effects of applying retinol topically on elderly volunteers. Researchers found that after 24 weeks, fine wrinkles were drastically reduced. Retinol was also found to improve skin damaged by UV radiation in another study.
Peptides are parts of proteins that are made up of amino acids. The peptides used in skincare are synthetic. A 2004 study from France found that a collagen-like peptide reduced the appearance of wrinkles for study volunteers. A 2017 review published in the journal Cosmetics summarized the scientifically researched benefits of topically applied peptides, including wrinkle reduction, UV protection, skin firmness, elasticity and skin tone.
Alpha hydroxy acids (abbreviated AHAs) are naturally derived from milk or plant sources. Two of the most common types of AHAs are glycolic acid and lactic acid. AHAs are often used to exfoliate skin and stimulate collagen production. A 2006 study conducted in Japan found that applying AHAs for six weeks rejuvenated skin that had been damaged by the sun. An Australian study on a skin cream containing AHAs, as well as vitamins B3, C and E, improved skin elasticity and decreased the appearance of wrinkles.
Salicylic acid is a compound extracted from plant sources such as white willow bark and wintergreen leaves. Several studies have shown the effectiveness of salicylic acid in treating mild to moderate acne. A 2013 study from China showed that antioxidant-optimized salicylic acid improved acne for 95 percent of study participants. An earlier study showed that salicylic acid was more successful at treating acne than benzoyl peroxide.
Ceramides are lipid molecules that occur naturally in your skin. Ceramides used in skincare are synthetic or extracted from plant sources. As an ingredient in face serum, their power seems to lie in their anti-inflammatory and moisturizing properties.
In a review published in the Journal of Clinical and Aesthetic Dermatology, a panel of dermatologists recommended moisturizers containing ceramides for acne patients. A 2011 study found that ceramides were an effective treatment for atopic dermatitis. A 2008 study also found that ceramides can effectively treat eczema.
Hyaluronic acid is a substance that occurs in your body naturally—mainly in your skin, joints and eye sockets. Its claim to fame is its astounding ability to hold 1,000 its own weight in water.
Hyaluronic acid has an anti-aging effect on skin. A 2011 study found that applying cream containing hyaluronic acid reduced wrinkles and increased skin hydration and elasticity for study volunteers. A 2016 study on the effectiveness of anti-wrinkle creams found that “The regular use of hyaluronic-acid containing anti-wrinkle creams for over three months showed clear and positive effects on wrinkle-depth and skin-tightness.”
Green tea extract is a concentrated form of green tea that has long been used in traditional Chinese medicine. It is a potent antioxidant, meaning that it fights against potentially damaging free radicals. Green tea extract’s antioxidant properties make it a gold-star ingredient in skin care. A study from the Medical College of Georgia found that green tea extract can actually rejuvenate dying skin cells. Green tea extract has also been shown to protect skin from UV radiation.
Green tea extract also has a moisturizing effect on skin. In a 2013 study, researchers applied a 6 percent solution of green tea extract to the forearms of volunteers. After 30 days of daily application, skin roughness decreased, while moisturization increased.
Bisabolol, also known as alpha-bisabolol and a-bisabolol, might sound like a scary chemical, but it’s actually a component of German chamomile. This ingredient is used in face serums because of its ability to calm and soothe sensitivity. It’s also well known for its strong antioxidant properties and its ability to help other ingredients penetrate your skin. A 2010 study from Korea found that bisabolol effectively whitened skin that had darkened due to hyperpigmentation. It is also sometimes used to naturally enhance the fragrance of beauty products.