A skincare routine is essential for maintaining skin health, enhancing appearance, and preventing future issues.
Within this regimen, moisturizers and serums are cornerstone products, each playing a unique role in achieving healthy, clear, and beautiful skin.
However, despite their shared goal of improving skin health, they differ significantly in formulation, purpose, texture, and how they should be incorporated into a skincare routine.
Therefore, in this article, I will delve deeper into these details and help you understand the differences between moisturizers and serums and how to use each product to achieve optimal skin health.
What is a Serum?
Serums are lightweight, highly concentrated formulations designed to deliver potent active ingredients deeper into the skin and initiate a biochemical reaction that will target specific skin concerns.
They are made up of small molecules that easily penetrate the outermost layers, offering solutions for skin concerns such as dryness, acne, lines and wrinkles, texture, or hyperpigmentation.
Serums are typically water-based, though oil-based options exist, catering to different skin types and needs.
What is a Moisturizer?
Moisturizers, on the other hand, are thicker, creamier formulations that aim to slow down transepidermal moisture loss by forming an occlusive barrier on the skin’s surface.
This barrier locks in moisture from the deeper layers of the skin and prevents it from evaporating while protecting the skin from environmental aggressors such as pollution and dry air.
These products are made with a blend of humectants, emollients, and occlusives and can have a thicker or lighter texture to suit various skin types and needs.
Ingredients: The Key Differentiators
Serum Ingredients
Serums are packed with active ingredients meant to solve specific skin issues.
Common ingredients in serums include:
Vitamin C: An antioxidant that protects the skin from free radicals in the environment and reverses cellular damage that leads to symptoms such as dullness, uneven skin tone, and pigmentary abnormalities.
Hyaluronic Acid is a humectant that brings moisture from the environment or the deeper layers of the skin to the surface, keeping the top layer of the epidermis hydrated, soft, and plump.
Niacinamide: An anti-inflammatory and antioxidant ingredient that helps improve the skin barrier’s function, resulting in smoother, more even-toned skin.
Retinol: A derivative of vitamin A that promotes cellular turnover and tackles skin concerns such as acne, wrinkles, texture, and pigmentary abnormalities.
Moisturizer Ingredients
Moisturizers contain ingredients that mainly aim to hydrate and protect the skin barrier.
These include:
Humectants like glycerin and hyaluronic acid, which draw water into the skin.
Emollients such as squalane, shea butter, and jojoba oil to smooth and soften the skin by filling in gaps between skin cells.
Occlusives like petrolatum and beeswax, which create a physical barrier to prevent moisture loss.
Texture and Consistency: A Tactile Difference
Serum Texture
Serums typically have a light texture, ranging from watery to gel-like, and are quickly absorbed into the skin, making them suitable for layering under other skincare products.
Due to their water-based formulation, some serums may feel slightly tacky or sticky upon application, but this feeling usually dissipates once the product is fully absorbed.
Moisturizer Texture
Moisturizers come in various consistencies, from light lotions to thick creams.
They are designed to be applied over serums and other treatments to lock in moisture and create a protective barrier on the skin’s surface.
The texture depends on the moisturizer’s formulation and the amount of water, oil, and other ingredients, making them versatile for different skin types and concerns.
The Effects on Skin
Immediate Effects
Serums: Due to the high concentration of active ingredients, serums have a more immediate effect on the skin, delivering quick and noticeable results, such as reduced acne, brighter skin tone, improved appearance of lines and wrinkles, and refined texture.
Moisturizers: Upon application, moisturizers provide an immediate hydrating effect, leaving the skin feeling soft, supple, and protected. Additionally, while moisturizers also contain active ingredients, they are not as concentrated as serums, so their effects may take slightly longer to become visible.
Long-Term Benefits
Serums: With regular use, serums can significantly improve the skin’s health and appearance, addressing concerns like lines, wrinkles, dark spots, acne, and overall skin texture.
Moisturizers: Continuous use helps maintain the skin’s hydration levels, prevents transepidermal water loss, and supports the skin’s barrier function, keeping it healthy and resilient against environmental stressors and pathogens that can exacerbate or trigger inflammatory skin conditions.
How to Use a Moisturizer and Serum Together?
Application Order
Serums should be applied after cleansing and toning but before moisturizing.
Their thin consistency allows them to penetrate deeply into the skin, where their active ingredients can be most effective.
Moisturizers are applied after serums to lock in the active ingredients from the previous product and ensure the skin remains hydrated and protected.
Application Frequency
Depending on their ingredients, both serums and moisturizers can be used daily.
Serums should be applied once or twice a day depending on the product’s potency and the skin’s tolerance.
For example, hydrating serums can be applied twice a day, while active serums containing ingredients such as exfoliating acids or retinoids should only be applied once a day (depending on the skin’s tolerance) as part of a nighttime skincare routine.
On the other hand, moisturizers should be used twice a day, in the morning and evening, to maintain optimal hydration levels and barrier health.
Choosing the Right Products for Your Skin
The selection of serums and moisturizers should be based on your skin type, concerns, and the results you hope to achieve.
Dry Skin
For individuals with dry skin, selecting a serum rich in hydrating ingredients such as hyaluronic acid, glycerin, and PCA is crucial, as these components help attract water into the skin and retain moisture.
On the other hand, avoid serums with high concentrations of alcohol or fragrances, as these can strip the skin and increase dryness and discomfort.
When choosing a moisturizer, those with dry skin should look for products rich in emollients and occlusives, such as shea butter, ceramides, and petrolatum, to nourish the skin and lock in moisture.
Avoid moisturizers with a high content of drying alcohols or those that are too lightweight, as they may not provide sufficient hydration or protection for dry skin.
Oily Skin
For individuals with oily skin, it’s beneficial to seek out serums that contain active ingredients such as glycolic acid or niacinamide.
These can regulate oil production, refine enlarged pores, and reduce shine.
On the other hand, oily skin should avoid oil-based serums or heavy oils, which can exacerbate oiliness and contribute to breakouts.
When selecting a moisturizer, those with oily skin should opt for lightweight, water-based formulas, often labeled as “non-comedogenic,” to ensure they won’t clog pores.
On the other hand, avoid heavy, occlusive moisturizers with ingredients like petrolatum or coconut oil, as these can be too rich and worsen oily skin concerns.
Sensitive Skin
For individuals with sensitive skin, it’s important to choose serums that contain calming and soothing ingredients, such as aloe vera, chamomile, panthenol, Centella Asiatica, etc., which are efficient at targeting inflammation and redness.
On the other hand, avoid serums with harsh exfoliants, high concentrations of vitamin C, or synthetic fragrances, as these can irritate sensitive skin, trigger adverse reactions, and even cause permanent skin conditions such as rosacea and dermatitis.
When selecting a moisturizer, those with sensitive skin should look for fragrance-free products that contain barrier-reinforcing ingredients, like ceramides and squalane, to nourish and protect the skin and reduce inflammatory reactions caused by environmental pathogens.
On the other hand, moisturizers with artificial colors, fragrances, or preservatives should be avoided, as these can exacerbate sensitivity and irritation.
Aging Skin
For individuals with aging skin, it’s advisable to select serums rich in antioxidants, such as vitamins C and E, and retinoids, which are known for their powerful anti-aging properties.
These ingredients help stimulate collagen production, reduce the appearance of fine lines and wrinkles, and improve overall skin tone and texture.
However, it’s important to avoid serums with harsh ingredients like high concentrations of alcohol or fragrances, which can irritate and dry out the skin.
When choosing a moisturizer, those with aging skin should look for products that contain hydrating and repairing ingredients like hyaluronic acid, peptides and ceramides to help restore the skin’s moisture barrier and improve its elasticity.
Avoid moisturizers that are too lightweight and do not provide adequate hydration or nourishment, as aging skin tends to be more prone to dryness.
My name is Simone and I am a certified skin specialist. I created this website to teach my readers how to take great care of their skin and I also like to occasionally share my honest opinions on skincare products I’ve tried. You can learn more about me here.
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