Written by Amy Scalia

Ancient Egyptians had lots of good ideas: writing, paper, medicine, clocks, calendars, and beauty oils. Yes, the same so-hot-right-now, essential beauty oils actually date back more than 5,000 years ago and were an important part of ancient Egypt’s infamously important beauty, wellness and self care routines.

From distilling plants and herbs like thyme, lavender, peppermint, cedar, rose, almond oil, and aloe for their nourishing oils, they realized a range of benefits to the mind, body and spirit. These natural but powerful essential oils can help calm, hydrate and rejuvenate the skin while also easing head tension, restoring mental focus or relaxing you for a great night’s sleep.

While this (really, really) old-school beauty secret is making a comeback, top dermatologists say facial oils remain an important, forgotten step in many beauty routines. The world of oils can be overwhelming, so here’s a breakdown of how they work and the biggest self-health benefits, as well as how and when to use them.

How Do Skin Oils Work?

"Essential fatty acids help to replenish and maintain the skin’s hydration and nourishment levels," says Melissa Allen, an esthetician and owner of a Cincinnati-based skincare spa. “But the body doesn’t produce these on its own, so we find them in external sources like beauty oils.”

Allen says you want to rebuild, protect and maintain skin's barrier from everything life tries to throw at it, like extreme environments and temperatures, sickness and inflammation. “Oils act as a carrier for other active ingredients to penetrate deeper into the skin, speeding up your skin's own healing process and repair,” she adds.

Beauty Oil Benefits

Essential oils are naturally brimming with vitamins that repair and protect. Argan oil, for example, is concentrated with vitamins A and E, which smooth fine lines and soften skin. Marula oil, a key ingredient in the Brightening Face Serum, has up to four times more vitamin C than in an orange. “This is an antioxidant that naturally reduces hyperpigmentation and brightens the skin’s appearance,” Allen says. "It can also stimulate deeper layers of the skin, creating more collagen and elastin, giving you firmer and bouncier skin.”

The most calming of all the beauty oils is lavender. The National Library of Medicine says lavender can calm everything from an insect bite to anxiety and restlessness. When blended with other oils, like roman chamomile in the Think Straight Roll On, they work together to calm the chaos and allow you to focus. When blended with the sandalwood, bergamot and neroli in the Sleep Tight Roll On, it provides a sense of calm and relaxation as you fall asleep.

Oils like the Tea Tree Oil have antimicrobial and anti-inflammatory properties, which in turn, kill acne bacteria and reduce the size of pimples. Also known as melaleuca, Tea Tree Oil can be diffused with an Essential Oil Diffuser to offer an antiseptic and fresh scent through your space. Add a few drops to water and you have an antiseptic room spray. You can also add a couple drops to your bath or dot on temples.

Tips for Using, Selecting Beauty Oils

When using a beauty oil, Allen says the most important thing to keep in mind is to save oil for the final step of your skincare routine. “If you apply oil first, any serums, treatments or moisturizers that follow won’t be able to fully penetrate the oil barrier,” she explains. “Oils are like the gatekeepers, not producers, of hydration. So start with humectants — ingredients found in lotions and cleansers — and then apply your beauty oil afterward to keep that moisture from escaping.”

Drier skin needs a heavier oil, like an avocado or almond oil, that will hydrate all day. Oilier skin types should look for one with a lightweight consistency. To save your skin from sensitivities in the colder months in particular, look to serums like the Sensitive Face Serum, which is specially formulated to be lightweight and easily absorbed by skin. Its vitamin-rich formula promotes moisture, prevents dehydration, and protects your skin from old man winter.

When comparing which serum or oil to use, Allen says purity matters. “The less refined and processed the better, so you’ll want to look for all-natural, pure-grade oils,” Allen says. “This makes them more expensive, but the less expensive ones have additive oils and byproducts as fillers that make them less effective.”