Apple Cider Vinegar Is A DIY Beauty Staple — But Is It Safe?

While the bathroom cabinet is home to most of our favourite skin-care products, there's another household space that's also proven to be valuable to our beauty routines: the kitchen. Ubiquitous ingredients like honey, milk, and sugar have been used as DIY beauty solutions for thousands of years, and continue to inspire new trends and innovations, too.

Apple cider vinegar is one such pantry staple. Made from fermented apple juice, the acidic liquid can be traced back to Babylonia and ancient Egypt, where it was said to have been used by Cleopatra as a facial cleanser. If legend is to be believed, Hippocrates prescribed apple cider vinegar to treat infections; American Civil War soldiers supposedly used it in wounds to encourage healing.

Today, we can find apple cider vinegar — or ACV, as it's called for short — in not just salad dressings and "health tonics," but also DIY recipes embracing the ingredient the way Cleopatra did: as a skin-care treatment for a clear, balanced, acne-free complexion. "Apple cider vinegar has been used by many to treat a number of conditions," says board-certified dermatologist Lian A. Mack, MD. Anecdotally, "numerous websites and blogs attest to the efficacy of it in improving acne and discolouration."

So, what is it about ACV that has some people reaching for it as a blemish treatment in the first place? "Apple cider vinegar is rich in malic acid, which is similar to alpha-hydroxy acid and has an exfoliating effect on the skin,” says Dr. Mack. This exfoliating effect promotes cell turnover, which sloughs away dead skin cells and helps clear out and prevent clogged pores (and therefore acne, too). That clarifying function, paired with the fact that it reduces melanin production in the skin, works to even out the overall complexion.

But as appealing as ACV might sound, the potency of the product carries its own risks — especially if you have sensitive skin.

Just like too much ACV in a dressing can ruin a salad, because of the high acidity, overdoing the stuff in your beauty routine can damage your skin. “Apple cider vinegar, although a natural ingredient, can do serious harm if used in excess," says Dr. Mack. "It lowers the pH of the skin, which can ultimately cause a chemical burn."

Jill Fichtel, MD, of Transformative Dermatology says that the best way to avoid an ACV-induced skin freakout is to always dilute the solution with water. Dr. Fichtel recommends following a recipe according to your skin type as follows: 1 part water with 1 part ACV for those with oily skin, 2 parts water with 1 part ACV for normal skin, and 3 parts water with 1 part ACV for those with relatively sensitive skin.

With that said, Dr. Fichtel and Dr. Mack both stress that those with extremely sensitive skin will do better avoiding ACV altogether. “I would not recommend this for patients with sensitive or dry skin," Dr. Mack says. "Due to its acidic nature, malic acid is innately irritating. People who have very dry skin, eczema, or even facial redness or rosacea may experience flare-ups of their conditions and are more likely to develop a contact allergy."

Another important factor to take into consideration is how often you’re using the ACV solution on your face. Dr. Mack advises doing so sparingly, as you would with many other potent chemical exfoliants: once or twice a week, depending on your skin type.

As an alternative to using ACV as a leave-on treatment or toner, Dr. Mack recommends trying it as a cleanser instead. Swipe a thin layer of vinegar quickly over the face using a cotton pad — which allows for more control when applying — then rinse it off with warm water and smooth on moisturiser afterward. And don't forget sun protection: "Any product that increases cellular turnover should be coupled with an effective sunscreen like Jane Iredale's Powder-Me SPF Dry Sunscreen, which also soothes,” Dr. Mack says.

There's also the lowest-risk option of investing in store-bought skin-care products that contain ACV, or malic acid, as part of a stabilised, regulated formula. "When used in the right concentration, malic acid can be safely used to reduce the signs of ageing, acne, and pigmentation," Dr. Mack says.

So, before you reach for the two-litre jug in the condiment aisle, consider the fact that ACV's efficacy may be outweighed by the potential for skin damage. The high acidity isn't something you should mess around with, and at the end of the day, the ingredient's strength isn't always a good thing — whether you're drinking it, washing your hair with it, or putting it on your face to make like an Egyptian queen.