What Is An Occlusive?

Occlusives in skincare are ingredients that help prevent water loss from your skin.

You can think of occlusives as a kind of protective seal that sits on top of your skin. It helps trap moisture to lock in hydration. Usually this protective seal still allows the skin to breath - so occlusives are absolutely a great and necessary part of good skincare products.

Occlusives can also assist your skin barrier in keeping irritants and allergens out of your skin. The skin's own sebum (skin oil) could be considered in part, a natural occlusive agent.

Occlusives usually work hand in hand with humectants (ingredients that draw moisture into the skin) to keep skin hydrated.

All great moisturisers are formulated with this in mind and usually contain both occlusives and humectants. 

As occlusive agents are usually considered oils, products for drier skin types tend to have more occlusive agents in them, whereas products for oilier types tend to have less occlusive agents.

The process of your skin losing moisture to the environment is more formally called Transepidermal Water Loss (TEWL for short). You’ll usually see products that claim to reduce TEWL, or have extreme 48 hour moisture protection - it’s usually in large part due to the occlusives used in the formula.

An occlusive moisturiser is usually just a moisture that is formulated to prevent TEWL and barrier protection above almost all else.

The typical occlusive moisturiser is a barrier cream that is formulated for professions that work around harsh environments like mechanics - these creams are usually a bit over the top for regular skincare and cosmeceuticals, which seek to provide other benefits too.

The purest form of an occlusive ‘moisturiser’ is petrolatum - or Vaseline. Petrolatum is usually used as a super effective occlusive and emollient within a formulation these days.

Hydrocarbons - Petroleum jelly, paraffin, mineral oil, squalene, caprylic/capric triglyceride

Fatty acids - Stearic acid, lanolin acid, oleic acid

Fatty alcohols - Lanolin, cetyl alcohol, stearyl alcohol

Phospholipids - Lecithin

Polyhydric alcohols - Propylene glycol

Sterols - Cholesterol

Vegetable waxes - Candelilla, carnauba

Wax esters - Beeswax, lanolin, stearyl stearate

Most oils aren’t as occlusive as we are led to believe. Some of the more occlusive oils contain higher proportions of oleic acid within them (part of the fatty acid list above), which also make them a bit more greasy.

Some of the more occlusive plant oils include:

Olive oil, macadamia oil, castor oil, shea butter etc.