The Importance of Moisturizers

It feels like everywhere you turn today, you’ll see an ad trying to get you to buy something. Skincare ads are no different. They’re just trying to get you to buy skincare products. There’s a plethora of skincare products out there – cleansers, toners, serums, eye creams, retinoids, moisturizers, just to name a few.

Some of these products are explicit about their purposes in the skincare routine, but what about the moisturizer? Is it really necessary to include the moisturizer in your skincare routine if you think you drink enough water daily? Yes. The answer is yes. This is because moisturizers can help you maintain a healthy skin barrier.

Now, the skin is the largest organ in your body and one of its main functions is to act as a barrier, protecting the body from harmful bacteria, chemicals, and radiation. This barrier also serves to keep moisture in the body, preventing dehydration.

Anatomy of the Skin

To better understand how the skin functions as a barrier, we need to first understand the basic anatomy of the skin. I’m sure you remember from high school that the skin is divided into 3 layers: the epidermis (outermost layer), dermis and hypodermis (innermost layer).  The epidermis is further divided into 5 layers, but the only one we’ll talk about is the stratum corneum (SC), incidentally also the outermost layer in the epidermis, because it’s the most important layer when it comes to skin barrier function.

The SC is commonly conceptualized using the “brick and mortar” model. The skin cells known as corneocytes are considered as the “bricks”, while the intercellular lipids – fats – are considered as the “mortar”, holding the entire structure together. These lipids act as a waterproof barrier for the SC, and it is these lipids that are lost when you wash your face. This is where moisturizers come into play, by replacing the lipids that hold the entire structure of the SC together.

Despite the lipids acting as a waterproof barrier, some water is needed in the SC to allow the skin to be fluid. Think about it this way, if your SC was rigid, when you put your foot down on a hard surface and applied pressure, your skin would split. Whereas with a little bit of water, you get some flexibility and resilience in the skin. There’s certainly much more to that when it comes to the role of water in the SC, as it also controls the enzymes that help breakdown the corneocytes. Without water, the corneocytes accumulate, your skin becomes flaky instead of peeling off nicely, and the SC becomes disorganized and full of cracks instead of being tightly packed.

Ingredients in a Moisturizer

As mentioned earlier, moisturizers help replace the lipids that hold the structure of the SC together. When choosing a moisturizer, one would need to know what are the important ingredients in the moisturizer and how these ingredients help maintain and repair the SC. A good moisturizer should always include these 3 main ingredients:

• Occlusives

Occlusives act as an impermeable oily layer on the surface of the skin to prevent the evaporation of water. They tend to be thick, greasy substances such as petrolatum or waxes. Commonly used occlusives include cetyl alcohol, lanolin, lecithin, mineral oil, paraffin, and stearic acid. Silicone derivatives such as dimethicone and cyclomethicone can also function as an occlusive. Oil-free products depend on dimethicone as an occlusive instead of using mineral or vegetable oils.

• Emollients

Emollients are substances that fills in the spaces between the corneocytes, providing a smooth surface and shine to the skin. Common emollients include butters, oils, esters, lipids, and fatty acids. A lot of occlusives also double as an emollient, such as dimethicone and cyclomethicone. Most emollients also help nourish the skin, so think of them as healthy food for the skin.

• Humectants

Humectants are like sponges, theoretically they pull water into the SC from the deeper layers of the skin. This allows the skin to feel smoother as the water fills in the gaps in the SC. Hyaluronic acid is one of the popular humectants used in moisturizers as it is naturally found in the skin. Other common humectants include vegetable glycerin, honey, sorbitol, and lecithin. Humectants can potentially make the skin even drier by pulling water into a damaged SC that doesn’t hold moisture, so they’re always used with occlusives to trap the moisture in the SC.

The basic working foundation of a moisturizer is that firstly, the humectant draws water from the deeper layers of the skin (or from the environment if the ambient humidity exceeds 70%) to the surface of the skin. Then the occlusives trap the water in place while the emollients improve the skin surface aesthetically by filling in the gaps between the corneocytes.

Besides the three main ingredients listed above, sometimes moisturizers contain active ingredients to serve certain purposes. Some commonly used active ingredients in moisturizers include ceramides, colloidal oatmeal, and antioxidants.  There have been several studies that indicate moisturizers containing ceramides are significantly better at improving skin hydration and helps increase intracellular lipid levels in the SC. Meanwhile, moisturizers containing colloidal oatmeal have been found to significantly alleviate skin dryness and itchiness.

The bottom line

Moisturizing is a step that many people leave out of their skincare routine because they think it’s unnecessary. But this could not be further from the truth. By using your moisturizer, you are consistently making sure that your skin cells are hydrated, which will help prevent breakouts and ensure better complexion.

When choosing a moisturizer, first identify if there is any skin problem that needs addressing. If the problem is dry skin, consider looking for a moisturizer that contains ceramides and colloidal oatmeal. Otherwise, if you have normal, healthy skin, any moisturizer that contains the three main ingredients listed above should suffice. Taking care of your skin is crucial when it comes to self-love and using a moisturizer to keep your skin healthy should be an important part of your skincare routine.