The Science Behind Using Panthenol in Hair Products

Panthenol is a popular ingredient for both skin and hair care
products. Hair care products that use this ingredient are said to have
enhanced moisturization effects and add thickness or body to the hair.
Proctor and Gamble has built their entire Pantene Pro-V
line of products to capitalize on the properties of this ingredient.
There seems to be a bit of confusion, hoever, about the role of
panthenol in a formulation and whether or not it is beneficial or
possibly even harmful for curly hair. A closer look at the chemistry of
panthenol should provide clarification about this ingredient.

The Basic Chemistry

Panthenol is a derivative of vitamin B5 (pantothenic acid) and is
known as a provitamin. Panthenol is what is called a chiral molecule, or
one that has a molecular structure that gives it a “handedness,” either
right-handed (dextrorotatory) or left-handed (levorotatory). These two
mirror-image enantiomers are not superimposable on one another, in the
same manner in which your two hands are mirror images of one another
rather than exact duplicates. Oftentimes, the two versions of a molecule
have differing chemical or biological properties. For cosmetic
purposes, panthenol is supplied either as a racemic mixture (50/50) of
both types of enantiomers or as the purified “D” version. This is most
relevant in skin care applications, as the D-version of panthenol is the
biologically active version.

The Properties

The multiple hydroxyl (-OH) groups on the panthenol molecule impart
most of the physical properties to it, most particularly its high
solubility in water and other solvents. Panthenol is a highly effective
humectant, a class of ingredients used in skin and hair care products to
promote moisture-retention. It has a highly hydrophilic and hygroscopic
chemical structure which attracts water from the atmosphere and binds
it to various sites along the molecule. Humectants typically possess
multiple alcohol (hydroxyl) or similarly hydrophilic sites (such as
ethers or ammonium groups), which are available for hydrogen bonding
with water molecules. Hydrogen bonding between humectants and water aids
in moisture-retention by minimizing water loss due to evaporation.

Panthenol is not only a humectant, but is also a useful moisturizer
and emollient. It spreads evenly on the surface of hair strands, forming
a smooth film on the surface of the cuticle. This film gives enhanced
coherence to the reflection of light from the surface of the hair, which
imparts significant gloss and shine. The smooth film also provides
excellent slip between adjacent strands of hair and detangling
properties. Panthenol is capable of penetrating the cuticle and entering
the hair shaft as well, where it aids in moisture retention and
provides volume.

It is important to note that sometimes penetration of the shaft by
ingredients can create a rough cuticle surface and lead to frizz, due to
swelling of the hair shaft. This may not occur for everyone and is
dependent upon several factors, including porosity of the hair and the
amount of the ingredient used in the product. It is a potential
undesirable effect, so keep this in the back of your mind when using a
product containing the ingredient.

Although there is a persistent rumor that panthenol creates waxy
buildup on hair, there is no evidence to support such an assertion.
Panthenol is not at all similar in structure to waxy materials. It is
also extremely water soluble, alcohol soluble, mildly soluble in
glycerin and is fairly easily capable of being mixed into most oils.
Additionally, panthenol has no component to its chemical structure that
would cause it to bind tightly to the surface of a hair strand. For
these reasons, it should be easily removed from hair by rinsing, washing
with mild shampoo and even conditioner cleansing. If one is
experiencing problems with build up and unpleasant hair texture when
using a product containing panthenol, the issue is more likely due to
other ingredients in the formulation.

Panthenol is readily absorbed by skin, and as the precursor of
vitamin B5, it directly impacts metabolic processes in epidermal cells.
It has been found to have many beneficial properties for epithelial
tissue, including increased hydration and improved elasticity and is
believed to promote cell regeneration. When used in shampoos and
conditioners, panthenol conceivably provides added benefit by improving
scalp health and potentially improving hair growth.

Final Thoughts

Panthenol is a naturally-occurring material that adds several
beneficial properties to hair care formulations. It is a humectant,
emollient, glossifier, detangler and moisturizing agent. It is highly
water soluble and is also easily removable with mild plant-derived oils
or via conditioner cleansing. When selecting humectant-containing
products, one must keep in mind the climate in which they live, how that
impacts hair and how they might expect a humectant to contribute to the
overall performance of their own hair within the constraints of that
climate. Also, depending upon the porosity of your hair and the type of
product being used, you may experience a roughened hair texture or some
frizz due to penetration of the hair shaft. If this should happen, it
might be best to discontinue use or to decrease use of the product.
Finally, experimentation is the best way to find out what works well on
your own hair.