Adding apple cider vinegar (ACV) to our products is all the rage right now, but what does it offer to our hair and skin? It contains many water-soluble components like alpha hydroxy acids, minerals and polyphenols.
 
Acetic acid must be found at a minimum of 4% to qualify something as a vinegar, and it is, in fact, what makes vinegars vinegar-y. (The name comes from the Latin word for vinegar.) It contains a number of minerals, including calcium, magnesium, phosphorus, and potassium in small quantities. It contains chlorogenic acid, a polyphenol that may act as an anti-fungal with anti-bacterial properties, and gallic acid, another polyphenol that acts as a great burn and wound healer, both of which work as good anti-oxidants and anti-inflammatories.
 
It has a strong, earthy smell, so it’s hard to use in large quantities, but we can easily mask 3% to 5% with fragrance or essential oils. It’s less acidic than other vinegars as the pH ranges from 3 to 5, which works well with hair and skin care products that should have pH ranges from 3.5 to 6. Substitute it at 2% to 5% for the same amount of water in your formulas.
 
ACV may be beneficial in facial care products thanks to the malic acid, which behaves like other alpha hydroxy acids (AHAs) by encouraging desquamation, the process of disrupting bonds between skin cells so they will slough off to expose newer and lovelier cells underneath. This helps to reduce the appearance of fine lines and wrinkles, make skin appear smoother, and may make pores appear smaller. It works as an antioxidant for our skin and the product, so it may slow down rancidity in oil soluble ingredients.

Please note that although we can use apple cider vinegar to pickle vegetables to preserve them, it won’t preserve our products in any way. It may act as an antioxidant, which can extend the shelf life, but it doesn’t prevent contamination from bacteria, yeast, fungus or mold.
 
It’s a great ingredient for those with acne prone skin as it acts as an anti-bacterial and anti-fungal. It could be added to a foaming cleanser, oil-free moisturizer, toner, gelled toner or spot treatment at 2% to 5% for all skin types. It’s nice at 0.5% in micellar water formulas or up to 3% in lotion based facial cleansers.
 
In foot care products, I use it at higher percentages where the smell isn’t a concern as I like the anti-fungal, anti-inflammatory, and exfoliating properties. Use it at up to 5% in place of 5% water in a cooling gel, lotion, cream, or butter.
 
ACV rinses are used as a way of returning hair back to its normally acidic state after washing with alkaline products, like cold process soap shampoo bars or those made with sodium coco sulfate (SCS). Start by combining 250 grams (8.82 oz.) water with 30 to 60 grams (1.05 to 2.10 oz.) apple cider vinegar to start, or including it in your rinse off shampoo or conditioner at up to 10% in place of up to 10% water in your formula.

Hair products, like shampoo and various conditioners, are generally formulated with a pH of 3.7 to 6.5 to match the acidic pH of our hair, except for “no more tears” products, which are closer to the pH of our eyes at around 7.5-ish. (The more virgin the hair, the more acidic it can be.) It is thought that an acidic rinse will return hair back to its normal pH. It could, but it may be too little, too late.
 
Our hair is hydrophobic or water hating thanks to a fine layer of bonded lipids on each strand, including fatty acids like palmitic, stearic, and oleic acids as well as wax esters, which help to mitigate friction and repel water. Alkaline products can remove this lipid layer, making your hair less hydrophobic and lipophilic (fat loving) and more hydrophilic or water loving. This makes it much harder to moisturize using oils, butters, esters, fatty alcohols, fatty acids and conditioners.
 
This is especially concerning as we count on positively charged or cationic ingredients like those we find in conditioning emulsifiers, like behentrimonium methosulfate, to mitigate the damage to our hair. It adsorbs to the hair strand in a phenomenon known as substantivity, an electrostatic attraction between our anionic or negatively charged hair strand and conditioner. If we can’t condition our hair, we can’t mitigate current damage and prevent it in the future.

Many of these issues cause the scales of our cuticle to lift causing temporary or permanent damage in the form of matting and tangling, increased friction, and the removal of cuticle scales, leaving the cortex and medulla exposed, resulting in weaker, drier looking strands unprotected from outside elements. It’s easier for water to enter when the lipids are gone and the scales lifted, causing the strand to swell, causing frizzies at best and increased friction and further destruction of cuticle scales at worst. More alkaline and water loving strands will have difficulty holding onto dyes and other colors as the cuticle fails to do its protective job, and our hair will appear duller, rougher, and less shiny as less light is reflected back.
 
All these types of damage are permanent, and there’s no way to fix them except temporarily between washings by using good conditioners and/or styling products.
 
Including ACV in our products is a great way to bring the kitchen into our chemistry!