There’s a rumor floating around that slathering moisturizer on oily skin can help it feel less slick. Maybe you’ve heard it from your best friend or an esthetician; perhaps you’ve read it on a popular Instagram influencer’s feed. The theory really picked up steam when facial oils came onto the beauty scene, with some experts suggesting that excessively oily skin is actually dry skin that’s overcompensating. “It’s one of those myths that runs rampant on social media and it’s just not true,” says Linda Stein Gold, M.D., a dermatologist in West Bloomfield, Michigan, and an Acne Store advisory board member. But there’s more to it than that: Here, Stein Gold shares the science that debunks this popular misconception and explains the best way to de-grease an oily complexion. 

First, what causes oily skin?

What we call “oil” is actually called sebum, an oily, waxy substance pumped out by the sebaceous glands found in your hair follicles. Sebum serves an important purpose: to naturally moisturize and protect skin. It coats skin’s surface so irritants, bacteria, and other bad stuff has a harder time getting past the skin’s barrier where they can do damage. All complexions produce sebum, but dry skin may make less of it, and oily skin, of course, is likely producing too much. Besides making your complexion look greasy, all that oil can pool in your pores causing clogs and, possibly, breakouts. 

So what turns on the taps in your sebaceous glands? “Sebum is mainly influenced by hormones such as androgens [male hormones produced to some degree by both men and women],” says Stein Gold. If you have excess androgens in your body, chances are you have excess oil on your skin and scalp, too. Genetics, gender, and race can also play a role in determining how oily your skin is, she says. “Sebum production tends to rev around puberty. Then it stays fairly constant and declines later in adulthood.” It’s one of the reasons that skin tends to get drier with age. 

Can moisturizer reduce oil?

That’s a case-closed “no,” says Stein Gold. “Your sebaceous glands are unaware of what’s happening on the surface of your skin, and whatever you apply topically isn't going to affect the production of sebum.” There are, however, a number of prescription medications that can slow overactive sebaceous glands, decreasing sebum and potentially prevent acne. Those include oral isotretinoin (Accutane, for example), hormonal birth control, and spironolactone, a pill that helps lower androgen levels. “There’s also a new medication that was just FDA-approved called Clascoterone cream that binds with androgen receptors in the skin and in the sebaceous glands and has been shown to potentially decrease the production of oil,” adds Stein Gold. 

"When you have excess sebum, you’ve already got natural moisturization."

Do you need to moisturize oily skin?

If you have oily, acne-prone skin, there’s still the question of whether or not moisturize at all. We know moisturizer won’t make your complexion any less oily, but does your skin even need one at all?  Not necessarily. “When you have excess sebum, you’ve already got natural moisturization,” says Stein Gold. “You don't necessarily have to add another moisturizer on top unless you're using acne drugs that are drying out your skin.” In that case, you want to look for a lightweight lotion or facial moisturizer for oily skin that says “non-comedogenic” on the label. That means it’s been tested and proved to not cause breakouts, Stein Gold says. You’ve probably seen mattifying moisturizers and wondered if they can dial down your oil production. While they won’t stop the amount of sebum your sebaceous glands expel, they can help absorb some of the oil on the skin’s surface so it doesn’t look as shiny. 

Oily skin types should reevaluate moisturization based on the seasons

The decision about whether to moisturize your oily-prone skin may also change depending on the time of year or the specific climate you’re in, Stein Gold says. “In the summer, people tend to be oilier, whereas in winter, they feel a bit more dried out.” And if you live in a tropical or humid climate but travel to a drier one (think Florida to Arizona, for example), your usually slick skin may feel a bit more parched and require some moisture. 

The takeaway: No, internet, you can’t make your skin any less oily with moisturizer. In fact, you may make it worse. It’s a slippery slope, literally. Instead, skip it altogether and go straight to your treatment products, or start out light. The best moisturizer for oily skin is one that is super lightweight or mattifying, as they do not add additional moisture on top of natural oils.