The best way to determine if something is comedogenic is to put it on your skin and see how your skin reacts. Of course, there’s a pretty significant downside to this test: If the product is comedogenic, you’ll have clogged pores or breakouts to contend with. Instead, defer to the comedogenic scale.

The comedogenic scale is a scientific measurement of how likely specific ingredients are to clog your pores or trigger breakouts. To determine an ingredient’s comedogenicity, scientists test the ingredients on human volunteers or on rabbit ears to see how the skin reacts.I Countless studies have been conducted to test the comedogenicity of various ingredients. Sadly, no central database lists every skincare ingredient (probably because that would be close to impossible to compile). But there are some popular ingredients that scientists have found to be likely to clog pores, and others that research shows are safe even for those with blemish-prone skin.

Early studies showed that heavy, greasy ingredients, like lanolin, are typically among the most likely to clog your pores.I As such, people long assumed that all oily substances are acnegenic. But now we know that’s not the case: In fact, many botanical oils have anti-inflammatory and antibacterial properties that can help treat skin concerns like acne and dermatitis.

These beneficial, non-comedogenic oils are what we use in our skincare formulations, like the best-selling Midnight Recovery Botanical Cleansing Oil. This luxurious oil cleanser is formulated with a slew of lightweight plant oils, including olive-derived squalane. The non-comedogenic formula emulsifies with water to thoroughly melt away dirt, oil, and other impurities (even waterproof makeup) without over-drying the skin. The unique cleanser is suitable for all skin types and can be used nightly to promote softer, more supple skin.

Oils have been used since antiquity to help soften and smooth the skin. Olive oil, for example, was widely used for body care throughout ancient Greece (philosophers called it "liquid gold"), while traditional Ayurvedic practices utilized numerous natural oils and butters as cosmetic ingredients. The majority of oils are emollients and possess notable skin-softening and smoothing properties. Research shows that emollients help improve skin barrier function, reduce dryness, and promote an overall more even skin texture.^III

To reap these benefits, reach for richer face oils, like the top-rated Midnight Recovery Concentrate. This Kiehl’s best-seller contains a blend of emollient non-comedogenic oils, including olive-derived squalane, evening primrose oil, and fragrant lavender essential oil, which work together to hydrate and smooth the skin. The top-rated formula boosts radiance and helps refine skin texture within just one night, while continued use helps firm the skin and diminish the appearance of fine lines. We recommend incorporating this indulgent oil into your nighttime anti-aging skincare routine for softer, younger-looking skin.