What Are Your Skin’s Natural Moisturizing Factors?

As a dermatologist, it’s clear to me that skin hydration is crucial for maintaining healthy-looking skin. And at the heart of skin hydration lies a group of key molecules known collectively as natural moisturizing factors. These compounds, which include amino acids and urea, are naturally present in the outermost layer of the skin and help to maintain optimal moisture levels. Keeping the skin moisturized can not only help protect against dryness but also reduce the appearance of dry, fine lines and make skin appear smoother. By understanding NMFs and their hydrating effects, you can better care for your skin.

• NMFs are a group of naturally occurring molecules found in the top layers of your skin. These molecules attract moisture to the skin and help maintain the skin barrier. 

• Amino acids, pyrrolidone carboxylic acid, lactic acid, urea, and electrolytes are all considered natural moisturizing factors.

• Age, environmental factors, and skincare habits can all affect the amount of NMF in skin.

• Natural moisturizing factors can also be found in nourishing skincare products like CeraVe Intensive Moisturizing Lotion.

Your skin's natural moisturizing facts are a combination of molecules contained in the top layers of your skin, known as the stratum corneum. The natural moisturizing factors consists of different molecules and acts as a humectant, meaning it attracts water, and is responsible for keeping your skin moisturized. It also plays a role in maintaining the skin’s natural moisture barrier. In simple terms, you can think of NMF as a soup of ingredients that help keep the outermost layer of the skin hydrated.

Initially, studies actually called NMF “naturally occurring humectants.”¹ It wasn’t until 1959 that the name “natural moisturizing factor” was published for the first time. Today, the mixture is known as NMF, and the different molecules are also referred to as NMFs.

Key components of NMF

As I touched on, the natural moisturizing factors aren’t just one molecule, but rather a mixture of different components. You can imagine them as a team that works together to keep skin hydrated. The main components of NMF include: 

•  Amino acids: These are the building blocks of the proteins in your skin. Amino acids present in the skin include arginine, glutamine, and histidine. 
• Pyrrolidone carboxylic acid: Otherwise known as PCA, pyrrolidone carboxylic acid is a naturally occurring hydrating agent.  
• Lactic acid: This alpha-hydroxy acid is considered an excellent moisturizer. 
• Urea: Urea is a water-absorbing molecule in the NMF. It helps maintain skin hydration and supports the overall function of the stratum corneum. 
• Electrolytes: These minerals (including sodium and potassium) help your body maintain balance. They are key in helping retain water in the uppermost levels of the epidermis. 

How Do NMFs Work?

Your skin produces NMF through a complex process that requires careful balance. The NMF forms when filaggrin—a protein found in the stratum corneum—breaks down. It splits into small molecules of amino acids, lactic acid, and other components of NMF. These molecules then draw in and retain moisture, hydrating the cells in the uppermost layer of the skin. And when the cells are hydrated, they expand and create a tighter seal. This helps enhance the skin barrier, contributing to its suppleness, elasticity, and general integrity.

NMFs are unique compared to other moisturizing ingredients because they work in harmony with your skin’s natural system.

What factors can affect NMF levels?

It’s possible for your skin’s NMF to become depleted. When this happens, it can increase the risk of dry or dehydrated skin. When NMF levels are low, your skin loses moisture more easily, leading to dryness and potentially worsening xerosis (the medical term for dry skin). If your skin feels less hydrated than usual, there could be a few reasons why.

•  Age: As you age, the water content in your skin can decrease. With less water, there’s less moisture for the compounds in NMF to hold onto.
• Environmental factors: Humidity, in particular, is closely tied to NMF levels. When humidity is lower, NMF has a thicker viscosity, which helps better prevent dehydration. 
• Skincare practices: Indulging in long baths and showers can dry out your skin. According to research, soaking in water can reduce the number of NMF molecules in your skin.² 
 
If you’re experiencing very dry skin, consult your dermatologist. 

How can you tell if you have extra dry skin?

You can often tell when skin is particularly dry based on how it looks and feels. Dry skin tends to look dull and may feel rough and scaly. It can also feel tight after cleansing and may sometimes be itchy and red. Below, find an overview of common signs of extra dry skin.

• Rough skin texture
• Flaky or scaly skin
• Tightness
• Itching due to dryness
• Redness

The molecules that make up your skin’s natural moisturizing factor can also be topical skincare ingredients. Amino acids, PCA, lactic acid, urea, and electrolytes can all be found in skincare products. Studies show that including NMF in skincare formulas can help manage dryness and promote healthy-looking skin.³ Researchers have also found that using products with both NMFs and ceramides can be particularly beneficial for boosting moisture.⁴

If you have dry to very dry skin, I recommend adding a product formulated with natural moisturizing factors into your body care routine. CeraVe Intensive Moisturizing Lotion is a great option for patients with extra dry skin. It contains three skin-identical ceramides—and 5% Hydro-Urea™, an innovative complex of NMFs that provide excellent hydration and help restore the skin barrier. This unique blend contains a potent combination of hydroxyethyl urea, glycine, alanine, serine, and sodium PCA to intensely hydrate and help reduce symptoms related to extra dry skin. 

The body lotion intensely moisturizes extra dry skin for up to 72 hours, helping relieve key signs of dryness, including itching, tightness, and flakiness.  In a clinical study 99% of consumers agreed that after use of the moisturizer twice daily for one week itch due to dryness on their legs was reduced.  

While this NMF moisturizer is made with dry skin in mind, anyone—even those with sensitive skin—can use it for noticeably smoother, softer, and healthier-looking skin. It’s also allergy-tested, fragrance-free, and pH-balanced.

How do you use CeraVe Intensive Moisturizing Lotion?

To use CeraVe Intensive Moisturizing Lotion, cleanse your skin and apply any treatment products. Then, apply a liberal amount of the lotion. You can repeat as often as needed, or as directed by a physician. I recommend starting with twice-daily application, once in the morning and once at night. Beyond that, listen to your skin. Pay attention to how it feels throughout the day, and if it feels dry, reapply.

The first step in managing dry skin is to focus on hydration. But moisturizer is just one step in any skincare routine. In order to care for dry skin, you’ll want to build a complete hydrating routine. Here are a few tips to keep in mind.

Take shorter showers and baths

As I mentioned, spending too much time in water can reduce the number of NMF molecules in your skin. To help relieve feelings of dryness, the American Academy of Dermatology recommends limiting showers and baths to 5-10 minutes.⁵ You can also try turning down the temperature and bathing in lukewarm water—higher temperatures can further dry out your skin. 

What you do after bathing matters, too. Pat your skin dry rather than rubbing it, and immediately apply a fragrance-free moisturizer while your skin is still damp to help trap moisture.

Use a body cleanser with ceramides

Ceramides are like the mortar between the bricks in your skin barrier and can help lock in moisture, and help protect your skin barrier. If your skin lacks ceramides, it can become more vulnerable to moisture loss, which may lead to dryness, tightness, and even itchiness due to dryness.

At CeraVe, you’ll find three essential ceramides in all our products. Remember, you want to apply skincare products to a clean canvas, and this is true for both face and body products.

Switch to fragrance-free products

Wear gloves to prevent scratching

Combat dry air with a humidifier

Unfortunately, there's no overnight cure for dry skin. But, using a humidifier while you sleep can help add moisture to the air and improve hydration. This can help keep your skin feeling comfortable and prevent further dryness.

For help choosing the right products for your specific skin type and skin concerns, use the CeraVe Find My Skincare Solution tool.