You walk into your favorite store at which to buy shampoo and conditioners for yourself and you’re immediately confronted with a vast array of products, most of them proclaiming to be pH-balanced. What’s a consumer to do? What if you don’t even have the faintest idea what ‘pH’ means? What if you’re harming your hair, your skin, your neighborhood, your child’s chances of getting into any Ivy League college, the earth if you use the wrong pH product? What’s a consumer to do?? And then, just when you think you can ignore the problem and it will go away, you’re confronted with the same choices when it comes to grooming your horse. You question: should I just shave my head and my horse at the same time and be done with this dilemma? Don’t despair, dear reader, hopefully we can help.
In recent years, the issue of pH has been in the forefront of discussion in the equine world, mainly within the area of horse grooming. To be quite honest, there has been a lot of misinformation generated as well, and the purpose of this column is to try to clarify some of those issues.
Hair is made up mainly of proteins and is actually fairly strong stuff. However, certain chemical processes can weaken hair and cause it to break or become brittle. Hair structure is made up of two main parts: the cuticle, or outer layer, consists of overlapping scales. The inner layer, or the cortex, is basically protected by the cortex. When hair is damaged, the scales of the cuticle may stand away from the cortex or even break off, exposing the inner layer and making hair feel dry and brittle. The cortex is made up of a chemical ‘string’ of proteins and gives hair its elasticity and strength. Alkaline products can penetrate through the cuticle/outer layer. As an example, most human hair color dyes are alkaline; they open up the cuticle and mix with the cortex, thus changing the color of the hair. Even diluted bleach with a pH of 9 can cause the scales of the cuticle layer to break off if used too often or mixed too strongly. When the cortex is exposed to further washing and environmental factors, it can dry out, loose elasticity and leave the hair prone to breakage.
Basically, pH scale measures the concentration of H+ (hydrogen ions) and OH- (hydroxide ions). More simply put, it is the measure of how acidic or alkaline a solution is. The pH scale ranges from 0, very acidic, to 14, highly alkaline, with 7 as the neutral number. Even though some products may have a slightly higher or lower number than 7 and could be considered ‘neutral’, e.g. a pH of 6.5 to 7.5, the scientific fact is that neutral pH is 7. Period.
The internal pH of most living cells is close to 7, and the pH of a healthy horse’s skin and hair is 7.0 to 7.4, essentially neutral. This neutral pH provides a barrier to both unfriendly funguses and bacteria. In fact, equine skin pH actually increases as a horse sweats, creating an environment more conducive for harmful bacteria and fungus to ‘set up shop’ dermatologically, so to speak. Because of this, it is very important to try to bring the pH back to normal, as close to neutral as possible. Everyone who has ever purchased shampoo for themselves as heard or read the term: pH-balanced. This is simply stating that a particular product, shampoo, conditioner, moisturizer, whatever it may be, has been balanced for a particular pH. As an example, the pH of human skin and hair is around 6.7 to 6.9, slightly lower than a horse’s. So, a pH-balanced shampoo will have a slightly acidic pH so it will rinse more cleanly, not leaving chemical residues behind.
Yet another way to understand the difference between acid and alkaline, or basic, solutions involved how they rinse off a surface. Bleach is a highly alkaline substance with a pH around 12. If you’ve ever gotten bleach on your hands, there’s a feeling of slipperiness and an inability to wash the bleach off. It may take 5 or 6 repeated rinses of clear water to get rid of the bleach and to have normal tactile sensations back in your fingers. This is because highly alkaline products do not mix well with water. The technical term is hydrophobic and, simply put, they bind to the protein of the skin, hair, cornea, etc. Acid-based products, on the other hand, are hydrophilic, that is, they mix well with water and are more easily rinsed off hair and skin and are much safer around the eyes. As an example, most prescription eye ointments and drops are acidic so they do not cause damage to the cornea, but are rapidly absorbed into the eye chambers.
In contrast, mildly acidic solutions have an opposite effect and flatten the cuticle, making hair easier to brush and look shinier. As an interesting aside, before the advent of modern hair coloring salons and technology, women would rinse their hair in vinegar after harsh chemical dying processes to make their hair more shiny and manageable.Because the pH scale is so ‘compact’, ranging only from 0 to 14, it’s important to understand how it works. Each pH unit represents a tenfold difference of the H+ (hydrogen ion) and OH- (hydroxide ion) concentration. That means that a solution of pH 2 is not twice as acidic as a solution of pH 4, but rather a HUNDRED times more acidic. If a horse’s skin and hair has a pH of 7, an alkaline solution with a pH of 10 is actually 1000 times MORE ALKALINE than normal or neutral.
Simple pH Chart
Sulfuric acid 1
Lemon juice 2Soda 3
Pure rainwater 6.5
Baby Shampoo 6.5
Baking soda 9
Drain Cleaner 14
The most important lesson to learn about pH and your horse’s skin and hair is simply this: it’s always best to try to bring the pH back towards neutral or normal.
Remember that sweating and dirt can raise the pH toward the alkaline side, so a neutral to slightly acidic pH product works best for cleaning and protecting the horse’s skin and hair. Although a more alkaline product may seem to clean better, it simply strips away all natural oils and opens up the cuticles, possibly causing hair shaft damage and making an environment in which funguses and bacteria can more readily establish themselves.
If there’s a question about a specific product, it’s best to contact the manufacturer and ask for a copy of the MSDS (Material Safety Data Sheet), which should contain the pH of the product in question. Or, you can test any solution or substance with a simple pH meter or litmus paper test. Also, the term ‘pH-balanced’ can, unfortunately, be twisted to mean what the manufacturer wants it to mean. Unless a reference point is provided, pH-balanced may be misconstrued. As an example, since horse’s hair and skin is normally around 7 to 7.4, a pH-balanced shampoo should be close to neutral to ‘balance’ the pH back to normal.