Moisturizer is a key part of most skin care regimens, but what does moisturizer do and how does it work, exactly? The benefits seem obvious—it moisturizes the skin to prevent dryness. You may moisturize every day, twice a day, but you may not understand exactly why it's such a healthy practice.

Moisturizer is not just for dry skin. Even if you have oily or acne-prone skin, you will likely still benefit from a balance of moisture and hydration. Here is how moisturizer works and why it's an important step in any skin care routine, regardless of your skin type.

What Is a Moisturizer?

A moisturizer is a skin care product that contains an emulsion of water, oil, and other ingredients, like antioxidants, preservatives, emulsifying agents, sunscreen filters, and more. Moisturizers tend to be creamy, but they can also have a gel-like texture.

The primary goal of a moisturizer is to increase and retain the moisture content of the skin. Although moisture may make you think of water, it actually refers to oil. The water content in skin is referred to as hydration, whereas moisture refers to the skin's oils or sebum. Compared to lotions that have a higher water content, moisturizers are formulated with both water and oils that add moisture and maintain hydration.

What Does Moisturizer Do?

According to Harvard Health Publishing, the way moisturizers work is simple: moisturizers supply water to the skin and contain an oily substance that seals it in.

Moisturizers are made with three main types of ingredients:

  • Occlusives: Oily substances that form a thin film over the skin and block the evaporation of water

  • Humectants: Ingredients that attract and pull water into the skin

  • Emollients: Moisturizing ingredients that soften dry, flaky skin

Research published in the Indian Journal of Dermatology suggests there is a fourth main moisturizing ingredient: squalene. Squalene is a lipid naturally found in the skin. The benefits of squalene include moisturizing properties for sensitive skin, antioxidant protection, and anti-aging benefits.

Though oil and water usually don't mix, moisturizers are uniquely formulated. If you take a look at the ingredients list on a moisturizer, you'll likely see water as the first ingredient. When you apply a moisturizer, some of that water evaporates. Thanks to the oils (a.k.a. occlusives) in the moisturizer, a lot of the water is held in and used to hydrate your skin.

Depending on the active ingredients, moisturizers can also help target specific skin concerns. For example, antioxidants like vitamin C and vitamin B3 (a.k.a. niacinamide) protect against free radical damage, improve hyperpigmentation, and reduce inflammation. You'll also find hyaluronic acid in many moisturizers because it helps pull the water content into your skin, effectively hydrating any dry skin. Some ingredients, such as amino acids, also help support skin barrier function.

Who Needs a Moisturizer?

Regardless of your skin type, you should moisturize every day. Although skin care is personal and your choices may depend on your unique skin concerns and preferences, nearly everyone can benefit from a boost of hydration.

Even if your skin is oily and does not appear outwardly dry, your skin's moisture and hydration may be imbalanced. Dehydration can lead to either excessive oiliness or excessive dryness. When skin is hydrated, it is less likely to appear dry or oily, so a moisturizer is key.

How to Use Moisturizer

When developing a skin care routine, a moisturizer should be the last step before sunscreen so that it locks in your previous products. To get the most out of your moisturizer, use it in the morning and evening on clean skin.

If you use other skin care products, this is the correct order of application: cleanser, toner, serum, spot treatment, eye cream, moisturizer, and sunscreen. The general rule of thumb is to apply your products from lightest to heaviest consistencies.

Like other cosmetics, moisturizers expire. Be sure to check the expiration information on your moisturizer package and use it within that time frame for best results.

What to Look For in a Moisturizer

When choosing a moisturizer, take a close look at the ingredients. A high-quality moisturizer will contain water to support the moisture barrier and soften skin.

Depending on your skin concerns and skin type, certain active ingredients may stand out to you. Hyaluronic acid and squalene help hydrate dry skin, whereas niacinamide and willow bark extract help balance oily skin.

It can be challenging for those with sensitive and acne-prone skin to find the right moisturizer, but the EltaMD Skin Recovery Light Moisturizer is a great choice. It's formulated to repair a damaged skin barrier, minimize irritation, and defend against free radicals.

Next time you apply your moisturizer, remember its benefits and appreciate all the good you're doing for your skin.


  • Lacey Muinos

    Lacey is a Southern California-based freelance writer who combines her passions—fitness, health, and a vegan lifestyle—with her work to help readers feel and be their best. Her work has been featured in Healthline, Livestrong, Verywell Fit, Eat This Not That, KinderBeauty, and more.

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