What Is An Occulsive Moisturizer?
Occulsive moisturizers are a category of moisturizer that is designed to form a barrier on the surface of the skin, trapping moisture and preventing water loss.
Occulsive agents physically prevent transepidermal water loss or water loss from the skin to the environment. The most commonly used occulsive ingredients is petrolatum, think petroleum jelly. Other occulsive agents are lanolin, mineral oil and silicones.
In order to understand how occulsive moisturizers work and whether your skin would benefit from using one, you need to understand a little bit about dry and dehydrated skin.
What Is Dehydrated Skin vs Dry Skin?
Dehydrated skin may feel dry and tight, but there may be other symptoms. Lack of water shows up as sunken eyes and under eye circles, as well as a dull complexion.
Fine lines and wrinkles may also be more noticeable, and the whole face may look shadowed. Inflammation as well as redness and congestion may also be signs of dehydration.
Dry and dehydrated skin are not the same thing. Dry skin is a skin type, while dehydrated skin is a condition. If you have dry skin, it means that you have fewer oil glands, and you were probably born that way or acquired it through aging. Without sufficient oil, the skin cannot retain moisture or create a strong barrier to protect itself. Dry skin tends to be flaky and tight- and most of the flaking happens around the eyebrows and around the nose. Dehydrated skin is caused by a lack of water, rather than oil.
Why Use An Occulsive Moisturizer?
Occulsive moisturizers work by providing the skin with a protective barrier that traps moisture and water in the skin, preventing transepidermal water loss or TEWL.
Transepidermal water loss or TEWL refers to the loss of water from the skin to the air, this often occurs in dry environments or in aging. As we age the ability of the skin to hold water decreases as the natural protective barrier of skin oils, ceramides, and amino acids decreases. This can often leave the skin feeling dry, tight and looking a little lakclustre.
Occulsive ingredients such as petrolatum or Vaseline, help to trap moisture in the skin, preventing it from being evaporated into the air. This helps the skin to maintain a healthy balance of water and support the healthy functioning of the skin.
The skin’s natural barrier is such a big part of how the skin protects itself and maintains moisture. When the skin barrier is damaged or not working as well as it could be the skin can become dehydrated, irritated or senstized. Occulsive ingredients help by acting as a protective barrier, doing some of the work that the skin’s natural barrier would usually be doing.
Now, occulsive ingredients aren’t just for skin that is dehydrated or needing a little protection, they may also help to generally improve the appearance of healthy skin as well. A number of studies have looked at the benefits of petroleum jelly for these benefits.
Petrolatum or petroleum jelly is considered to be the most effective occulsive moisturizer with its use reducing transepidermal water loss by more than 98%, 170 times more effective than olive oil.
The use of occulsive ingredients to improve the dewy, glowy look of the skin has become popular with the trend known as slugging. Slugging refers to the practice of using an occulsive ingredient over the top of a water-based serum and/or moisturizer to improve the water content and fullness of the skin.
What Are The Three Types of Moisturizers?
Occulsive
Occulsive moisturiziers create a physical barrier on the skin to prevent water loss to the air. Common occulsive ingredients include petroleum jelly, mineral oil, silicone, waxes and lanolin.
Emmolients
Emmolients are moisturizing ingredients that soften the skin, make it feel more comfortable and help keep the skin supple. Emmolients are ingredients such as butters and oils. Some emmolients have mild occulsive properties.
Humectants
Humectants are hydrating ingredients that help to pull water into the skin, think hyaluronic acid. Humectants need to have an emmolient or occulsive ingredient applied over the top to ensure that they provide the skin with the hydrating benefits.
Are Occulsive Ingredients Vegan?
Not all occulsive ingredients are vegan. Ingredients such as beeswax and lanolin are not vegan ingredients as they are derived from animal or animal byproduct ingredients. However, ingredients such as petroleum jelly, mineral oil and silicones are considered to be vegan ingredients.
How To Use Other Skincare Products With Occlusive Moisturizers?
As occulsive agents are used to trap water under a protective barrier on the surface of the skin, they are usually applied last at night and second last, before your sunscreen, during the day.
When layering your skincare products it’s best to start with the lightest product first such as serums or toners then move toward your heavier products. Occulsive moisturizers work best when the skin has been provided with moisture or water in the under layers. Using your serum or moisturizer under the occulsive moisturizer can help to trap water in the skin, helping to improve the appearance of the skin. This technique of layering water and moisture under an occulsive agent is called slugging.
As occulsive ingredients tend to be thick, most people will use them at night so that it doesn’t disrupt your makeup. However, if you have dry skin that needs that extra protection during the day, occulsive moisturizers can be used then too.
Can All Skin Types Use Occulsive Ingredients?
The best thing about slugging is that, depending on the occulsive ingredient that is being used, it can be used by all skin types, even congested skin.
If you have congested, oily or blemish-prone skin, petroleum jelly can be a good option as it is considered to be non-comedogenic or doesn’t clog pores. Some research has suggested that dehydration is linked to inflammation and breakouts.
Most skin types including, sensitive, dry, dehydrated, inflamed and congested are likely to benefit from using an occulsive moisturizer. The main thing to remember, particularly if you have congested skin is to cleanse well before application as you don’t want to trap makeup residue under the protective barrier that occuslive moisturizers provide.
Can I Put Retin A Over Occulsive Moisturizers?
This is a little bit of a tricky question. As tretinoin or retinol products can be irritating to the skin you may often be advised to use the on top of your moisturizer to reduce the associated senstivity.
However, occulsive moisturizers are likely to reduce the effectiveness of the active if they are applied after the occulsive ingredient. It may be best to apply it after the moisturizer and consult with your dermatologist or doctor about reducing the frequency or exposure time to the retinoids.
Occulsive ingredients can help to protect the skin and reduce the irritation that is associated with retinol or retinoid use.
What Are The Side Effects of Occulsive Moisturizers?
There are no specific side effects to the use of occulsive ingredients, they are considered to be safe for use. However, in some skin types and seasons, they may be too heavy for the skin. This may cause some milia or bumps to occur. If this is the case, reduce the frequency in which you use the occulsive moisturizer or stop its use altogether.
References:
Purnamawati S, Indrastuti N, Danarti R, Saefudin T. The Role of Moisturizers in Addressing Various Kinds of Dermatitis: A Review. Clin Med Res. 2017;15(3-4):75-87.
Sethi A, Kaur T, Malhotra SK, Gambhir ML. Moisturizers: The Slippery Road. Indian J Dermatol. 2016;61(3):279-287.