How to Tell If Your Makeup Is Oil- or Water-Based

We've all been there: you've completed your hair and makeup routine, the outfit is flawless, and you're ready for a night on the town. However, by the time you get to your first destination, your base makeup looks like it's been on for no less than 24 hours — it's blotchy, has started to settle weirdly into dry patches, and generally looks worse for wear. The issue could stem from a multitude of causes, but more often than not, it's likely because you mixed oil- and water-based products.

"Oil and water, without the help of any emulsifiers, will separate," Krupa Koestline, founder and chief chemist at KKT Labs, tells POPSUGAR. For those unfamiliar, emulsifiers are ingredients that mix and trap oil and water together. "Oils have water-fearing chains that physically repel themselves from water. You see this when eating salad when you try to mix olive oil with balsamic vinegar. No matter how much you shake it, the two will not mix."

So, how does this translate to your makeup routine and is there a way to easily identify if your makeup products are oil or water-based? Koestline answers these questions and more, ahead.

The best way to tell if a makeup product is oil- or water-based is by looking at the ingredient list. "In terms of complexion products like foundation, most of them on the market are water or silicone-based," Koestline says. This applies to various items in the category that have a liquid consistency, like concealer, liquid bronzer, or blush. Still, for oil-based products, in particular, it's a little easier to decipher. "Usually, at least two to three oils will be in the top five to seven ingredients on the list," Koestline says. "For example, the Westman Atelier Vital Skincare Complexion Drops ($68), an oil-based foundation, lists avocado oil and pomegranate seed oil very high up on their ingredient list. The RMS UnCover Up Cream Foundation ($52) starts with jojoba oil, caster seed oil, and meadowfoam oil."

Westman Atelier Vital Skincare Complexion Drops

From

$68

$68 at Sephora

RMS UnCover Up Cream Foundation

From

$52

$52 at Amazon

Water-based products, on the other hand, will typically list a mix of emollients, emulsifiers, and humectants in the first five to seven ingredients. "Typical ones you'll see include various esters like coco-caprylate/caprate, ethylhexyl olivate, various types of palmitates, isododecane, and alkanes, like c9-12 alkane or coconut alkanes," Koestline says.

For good measure, if you're looking for a silicone-based foundation, it'll likely have top ingredients that end in "cone." "Think along the lines of dimethicone, trimethicone, etc," Koestline says.

There are numerous reasons why oil or water-based products are created, from market research to demographic intent. "Some ingredients are only solvent in oil (editor's note: this means that they can only be dissolved or dispersed in the substance), while others are only solvent in water," Koestline says. "Market demand for certain textures also have to be considered. Most foundations we see on the market today are water or silicone-based as they tend to have a lighter texture, are less likely to clog pores, and can be manipulated to be longer wearing without feeling heavy."

Still, there is a place for oil-based foundations, especially when you consider certain skin types and textures. "Some people have a preference for these or even more wax-based foundations," Koestline says. These people typically have dryer skin or are more mature and prefer the glow that an oil-based foundation leaves behind.

Your skin type will likely dictate whether or not you prefer oil or water-based products, but your lifestyle does, too. "People with normal-to-oily skin typically prefer the texture of water and silicone-based foundations," Koestline says."They feel lighter on the skin, more spreadable, and there is less fear about it being comedogenic." People who also wear foundation for long periods, like performers or entertainers, usually also fall into this camp. "They tend to like the lightweight texture of water and silicone-based foundations," Koestline says.

If you have dry or mature skin, you may find that oil-based foundations feel nourishing and extremely comfortable on the skin, so be sure to build the rest of your routine around that fact, as well.

Now that you have the inside scoop about the difference between oil and water-based makeup products, it's time for you to go forth and prosper. Remember, if you mix a water-based primer with an oil-based foundation (or vice versa), you won't get the benefits and results that you are looking for. Chemists can use various emulsifiers to manipulate oil into water or water into oil in a formula that holds up over time. At home, that's likely not an option, so keep an eye out during your next trip to Sephora so that you can have budge-proof makeup for wherever the night takes you.

Ariel Baker is the assistant editor for POPSUGAR Beauty. Her areas of expertise include celebrity news, beauty trends, and product reviews. She has additional bylines with Essence and Forbes Vetted.