Just because something works inside your body, that doesn’t necessarily mean it will work on the outside.

Yet companies and consumers will still peddle such a concept, because having a hot ingredient can sell a product. Even if it’s for beauty instead of food.

Take the Garnier anti-puff eye roller with caffeine as one such example.

The marketing verbiage is careful to NOT say that the caffeine is responsible “for a brighter, more rested look” when using it. However, you can bet there are many people who assume that the caffeine is helping to make their under-eye bags more awake.

The problem? As a neurostimulant, caffeine only works inside the brain.

When it comes to this famous fruit-derived vinegar, there is a legit scientific rationale as to why it may help your skin. However, the mechanisms of action are different than what happens when you drink or eat it.

Is it okay to put ACV on your face?

Even when it comes to the health benefits of drinking cider vinegar, there is limited formal research. Uses for skin care, like serving as a face toner, removing skin tags, and whitening skin have not been the topic of any peer-reviewed human study. As such, the safety and efficacy of putting apple cider vinegar on your face overnight, or even momentarily to tackle a blemish, remains somewhat unknown.

There is anecdotal evidence that some dermatological uses may work, based on the chemical composition of ACV. There are also countless first-hand stories and reviews online of people who purport to use it successfully for acne, hyperpigmentation, and wrinkle prevention.

What’s inside and why it may help

organic tempeh scramble mad with Bragg yeast and amino acids

You already know it can help your diet. How it can help you achieve better, healthier looking skin is the result of two key ingredients inside.

Whether it’s Bragg’s or a less popular brand like Eden Organics, Dynamic Health or Fleischmann’s, the chemical composition of apple vinegar is comparable.

Organic vs. non-organic and raw vs. pasteurized could influence the antioxidants (chlorogenic acid, gallic acid) and the probiotic content. Yet those are not the active ingredients for skin care.

Research suggests the probiotics all die off after the fermentation process, though the amount of prebiotics they create – “the mother” – is higher when organic apples are used. (1)

ACV contains chlorogenic acid, which is what gives coffee most of its antioxidant activity. There’s also gallic acid, which is a common phenolic compound.

Both of these antioxidants are only in trace amounts in the vinegar. (2) (3)

The ORAC value of raw apple cider vinegar is only 564 and that’s for 100g (3.5 fluid oz). When you put it on your face or body, the amounts of antioxidants you’re getting is really too trivial to matter. Likewise for drinking it.

Anti-aging, such as wrinkle appearance and skin lightening, the reduction of pimples and blemishes, and being a skin tag removal remedy – these skin benefits are the result of one or more of the following ingredients, if they’re happening when you apply the vinegar topically:

acetic acid molecular structure and chemical formulaAcetic acid

The pH level of ACV can range from 3.1 to 5. The compound responsible for almost all of that acidity is an organic colorless compound called acetic acid. Typically 5% of the vinegar is acetic acid.

It’s responsible for most of the sour flavor. If you use apple cider vinegar for face toner, it’s the main chemical which causes the burning sensation. (2)

Malic acid

The percentage of malic acid in apple cider vinegar is typically 1/20th that of the acetic acid content. Assuming the acetic acid is at 5%, it means the vinegar will have about 0.25% malic acid.

Unlike lactic acid which is sometimes derived from milk/dairy, malic acid is always vegan. Apples happen to be the richest natural source. Other fruits like nectarines, cherries, peaches, and bananas also contain relatively high amounts.

Exfoliation and antimicrobial activity

The reason apple cider vinegar is good for skin is exfoliation and antimicrobial activity.

It can help kill microorganisms on your face such as Propionibacterium acnes bacteria. That’s not the root cause of acne but their presence can increase the severity of breakouts, by promoting inflammation and redness. That’s especially the case with cystic nodular acne.

Along with glycolic and salicyclic acids, malic is a common exfoliative agent used in dermatological products. Many chemical peels use it to remove dead skin cells.

Glacial acetic acid, which is when the acid has less than 1% water content, is commonly used in skin care products. It solidifies into solids/semi-solids at room temperature, then liquefies at warmer temperatures such as body heat.

Since it’s a weak acid, acetic doesn’t have the best exfoliative ability. Even though it’s not suitable for strong peels, leaving apple cider vinegar on face overnight is better than alpha hydroxy acids (AHAs) because it’s milder and therefore, can be used more frequently and left on for longer periods of time.

As with retinol, regular or daily use of an exfoliator will increase your cellular renewal rate. In other words, how fast the life cycle is of the skin cells on your face.

Why this has anti-aging advantages is because during youth, the cell turnover rate is exponentially higher. As we age, the rate decreases. By increasing the rate, fine lines and wrinkles are slower to form. This has been confirmed from multiple decades of research using retinoids, whose main benefit also is exfoliation. (4)

Side effects on skin, scalp, and body

Just as the acidity of undiluted ACV can be damaging to your teeth enamel when you ingest it, similar effects can occur on the surface of your skin. As with retinol face cream, you probably will want to start with a milder strength of vinegar, if using it as a toner or leaving on as an overnight mask.

Possible side effects of apple cider vinegar on skin will be excessive burning, redness, irritation, and skin flaking. Avoid contact with eyes and mucous membranes like the nose and lips, as those are even more prone to these reactions. Allergies to vinegars are extremely rare.

How to use on face safely

diluting 1 tbsp of apple cider vinegar in 1 cup of water

1. To start, use a 9:1 diluted mixture of water to vinegar. That equals 2 tablespoons of ACV per one cup of water (8 oz).

male using cotton ball soaked in cider vinegar on facial acne

2. Dip a sterile cotton ball in the mixture and dab on your face.

3. For a toner, leave on for 1-2 minutes, then rinse. Leave it on for 5-30 minutes if it doesn’t bother you. It will be dry to the touch after the first 10 minutes.

4. The best time to use apple cider vinegar on face is before bed, if you’re using it once-per-day. This is because some of your outer dead skin cells will be removed, which increases your skin’s sensitivity to UV light. By doing it before bed, your skin has some time to heal in the dark. Similar to retinol creams, you can leave apple cider vinegar on your face overnight.

5. If side effects don’t occur, you can increase the strength. Over time, many people find a 50/50 dilution of vinegar and water offers the right benefits, without excessive irritation.

6. How often you should use apple cider vinegar on your face is daily. If too much irritation occurs, try every other day or twice weekly. Over the course of several weeks to a couple months, your skin should be able to build up the tolerance to a once daily application.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.