Water plays a central role in making sure your skin stays healthy, smooth and radiant, so it only makes sense that every skin care aisle is lined with products that promise to hydrate and moisturize skin. But what many of us may not realize is that although they are often used interchangeably, moisturizing and hydration are not exactly the same thing. While both are key in providing skin with much-needed nourishment, knowing the difference will help you make the best choice when targeting your skin’s specific needs.
What’s the Difference Between Hydrating and Moisturizing?

Moisturizers and hydrators both address the importance of making sure the skin is getting all the water it needs to fight dryness and dehydration, premature signs of aging and environmental damage. The difference, however, lies mostly in how they go about achieving these results.

“Hydration [refers to] the water content within the cells that leads them to swell and be plump and bouncy, thus reflecting light well. If water flows out of the cells and the cells are dehydrated, they can become shriveled, which leads to lackluster skin,” explains Dr. Anna Guanche, M.D., a board-certified dermatologist in Los Angeles. This means that when you’re using a topical hydrator, you’re infusing your cells with water and improving your skin’s ability to absorb moisture and nutrients.

On the other hand, moisturizing is about trapping and sealing in moisture to build the skin’s protective barrier, prevent water loss and keep the skin soft and smooth, says Dr. Tsippora Shainhouse, M.D., F.A.A.D, a board-certified dermatologist in Los Angeles.
How to Know if You Need a Hydrator, Moisturizer or Both

If your skin tends to be on the dry side, it’s easy to assume that a healthy dose of moisturizer is all it takes to restore its plump appearance and youthful glow. While this may be true at times, it’s also possible that your skin may not, in fact, be dry but dehydrated. And if the latter is true, then a hydrator is what you need to get the job done.

To know if your skin is dry or dehydrated, it’s important to take note of your skin’s condition. The skin has a natural lipid barrier that protects itself from damage and water loss. If you’re prone to having dry, flaky skin, it’s a tell-tale sign that it’s not producing enough lipid cells to form a protective barrier, making it unable to lock in moisture. And that’s where moisturizers come in.

“A moisturizer’s job is to reduce the amount of water that evaporates off of the skin to minimize transepidermal water loss. They lock in and seal in moisture,” explains Dr. Guanche. Moisturizing is particularly helpful for skin that is dry and peeling or flaking after undergoing a chemical peel, using Retin-A or during the winter, Dr. Guanche adds.

Meanwhile, if you’re dealing with a dull and lackluster complexion with fine lines and wrinkles becoming more noticeable, your skin may be battling dehydration. “Dehydrated skin means the cells are parched and starved of water. When this happens, they are not plump and volumized and appear shriveled collectively,” explains Dr. Guanche. “People can have hydrated but dry skin or dehydrated but moisturized skin. Ideally, we want hydrated, bouncy, swollen cells that have topical moisture locked into them,” she explains.
How to Pick the Right Hydrator or Moisturizer

Drinking plenty of water is still the easiest way to hydrate your skin, but those with dehydrated skin may want to supplement with a topical hydrator that binds and draws water into the cells, suggests Dr. Guanche. Natural humectants allow the skin to improve its ability to hydrate itself over time, so look out for products that contain hyaluronic acid, aloe, honey, alpha hydroxy acids and marine extracts. Synthetic humectants, glycerin, urea and propylene glycol are some of the ingredients you want to keep an eye out for.

“Hydrating ingredients are generally appropriate for all skin types. They are water-soluble, won’t clog pores and should be devoid of alcohols so they don’t actively dry out or irritate the skin surface,” adds Dr. Shainhouse.

As for moisturizers, there is a wide variety of options in terms of formula and ingredients. “Moisturizers can be lighter or heavier and formulated for different seasons and different skin types,” says Dr. Shainhouse. “Warm, sweaty spring and summer months may call for a lightweight gel or light lotion, while dry, cold and windy fall/winter weather may require heavier products with ceramides, oils (coconut, almond), butters (shea or cocoa) or dimethicone,” she notes. These ingredients are known not only for their moisturizing and nourishing effects but also for their ability to counter the signs of aging and free radical damage.

To choose which type of moisturizer is best for your skin type, Dr. Guanche says, “For acne-prone skin, a light, oil-free moisturizer works best, usually in the form of a lotion. These have less oil and more water content. For combination skin, a lotion or cream will do fine, while a serum or a more emollient cream is best for dry skin types.”

For best results, hydrators and moisturizers should be applied morning (before sunscreen) and night. “You can apply moisturizing lotions or creams after applying your hydrator so it doesn’t peel,” Dr. Guanche adds.