Apple cider vinegar has some properties that could benefit skin, but the evidence is thinner than the internet suggests, and the risks of irritation are real. It contains malic acid (a mild chemical exfoliant) and acetic acid (which temporarily lowers skin pH), but clinical research has not confirmed most of the bold claims made about it. Here’s what we actually know.
What ACV Contains That Affects Skin
Apple cider vinegar is roughly 4 to 8 percent acetic acid, along with small amounts of malic acid, a type of alpha hydroxy acid (AHA). AHAs are well-established chemical exfoliants found in many skincare products. They work by loosening the bonds between dead skin cells on the surface, helping them shed more easily. This is the most credible mechanism behind ACV’s skin benefits: the malic acid may gently remove the outermost layer of dead skin, leaving the surface smoother and brighter.
The catch is that the concentration of malic acid in ACV is low compared to formulated AHA products, which typically contain 5 to 10 percent glycolic or lactic acid at a controlled pH. So while ACV does contain a legitimate exfoliating ingredient, it delivers it in an unpredictable, uncontrolled dose alongside acetic acid, which is an irritant.
The Eczema Claim Doesn’t Hold Up
One of the most popular claims is that ACV soaks can help eczema by restoring the skin barrier and lowering skin pH. A pilot study published in the journal Pediatric Dermatology tested this directly. Twenty-two participants, half with atopic dermatitis and half without, soaked one forearm in diluted ACV (0.5 percent acetic acid) and the other in plain water for 10 minutes daily over 14 days.
The results were discouraging. ACV soaks had no significant effect on skin barrier integrity. Transepidermal water loss, a key measure of how well the skin holds moisture, increased slightly right after soaking but returned to baseline within an hour. More concerning, 73 percent of participants reported skin irritation from the ACV arm, which improved only after they stopped the soaks. Plain water performed just as well without the side effects.
Mild Exfoliation and Toning
Where ACV may have a modest role is as a diluted toner for people with oily or acne-prone skin. The acetic acid creates a mildly acidic environment on the skin’s surface, which can help tighten pores temporarily and remove excess oil. The malic acid contributes a light exfoliating effect that can improve skin texture over time.
This isn’t dramatically different from what you’d get with a formulated toner or AHA serum, and those products are designed with stable concentrations and buffered pH levels. But if you prefer a simple, inexpensive option, a properly diluted ACV toner is a reasonable choice for non-sensitive skin types. It won’t replace a dedicated chemical exfoliant, but it can complement a basic routine.
How to Dilute It Safely
Undiluted apple cider vinegar should never go on your face or body. The standard dilution for a toner is about 2 tablespoons of ACV in 8 ounces of water. If you have dry or sensitive skin, cut that to 1 tablespoon or less per 8 ounces. Apply it with a cotton pad after cleansing, let it dry, then follow with moisturizer.
Some people add a teaspoon of witch hazel for extra oil control, or a few drops of lavender or chamomile essential oil. Skip these additions if your skin is reactive or dry, since they can compound the drying effect of the vinegar. Start by using the toner every other day and watch for redness, stinging, or flaking before increasing frequency.
Chemical Burns Are a Real Risk
The most serious risk with ACV is chemical burns, particularly when it’s applied undiluted or left on under a bandage. A case reported in The Journal of Clinical and Aesthetic Dermatology described a 14-year-old who applied undiluted ACV to moles on her nose for three consecutive days, covering the area with bandages each time. By the second day she had significant redness and irritation, and the skin eventually eroded, leaving open wounds.
Occlusion (covering treated skin with a bandage or wrap) dramatically increases the penetration of acetic acid and the likelihood of a burn. Even at normal concentrations of 4 to 8 percent acetic acid, vinegar can erode skin when left in prolonged contact, especially on the face where skin is thinner. Never apply ACV under bandages, and never use it at full strength on your skin.
What Not to Combine It With
Because ACV is acidic (typically pH 2 to 3), it can interact poorly with other active ingredients in your skincare routine. Niacinamide, a common ingredient in serums and moisturizers, can convert to niacin at pH levels below 4, which causes flushing, redness, and tingling. If you use a niacinamide product, apply it at a different time of day than your ACV toner, or wait at least 15 to 20 minutes between them to let your skin’s pH normalize.
Retinol and vitamin C serums are also best kept separate from ACV. Both are already potentially irritating on their own, and layering them with an additional acid increases the risk of over-exfoliation, peeling, and sensitivity. A simple rule: use ACV toner in the morning and stronger actives like retinol at night, or alternate days entirely.
The Bottom Line on Skin Benefits
Apple cider vinegar is a weak, imprecise version of ingredients that already exist in well-formulated skincare products. Its malic acid content offers mild exfoliation, and its acidity can help with oil control. But it has failed to demonstrate benefits for eczema, it irritates the majority of people who soak in it, and it carries a genuine burn risk when misused. If you enjoy using it as a diluted toner and your skin tolerates it, there’s no reason to stop. But if you’re looking for real results with chemical exfoliation, acne control, or skin barrier repair, a product specifically designed for those purposes will outperform ACV every time.