Given that all hair is made up of the same “ingredients” and shares the same anatomy, why is there such a rich variety of hair types, or hair structures? Structure is important because not only is it the foundation on which a hairstyle is built, but it also determines how hair interacts with hair care products. Through extensive research, Pantene scientists have differentiated three distinct hair structures: Fine, Normal-Thick, Colored. They are uniquely differentiated according to their physical and chemical properties, including their distinct inter-fiber relationships.

The starting hair structure affects the choice of ingredients for a formula, the levels of ingredients in a formula and the way in which the ingredients are deposited on the hair. The New Pantene line-up, with its focus on hair structure, is designed to deliver customized results.

But what elements define hair structure? Whether fine, normal-thicker colored (which can trump what you were born with in regard to choosing hair care), hair structure is dependent on three factors: surface properties, the degree of curl, and hair fiber diameter.

Breathtaking Architecture: The Structure of Hair

What’s on the Surface?

When scientists talk about the surface properties of hair, they’re basically talking about whether hair is chemically treated or virgin. When hair is color, relaxed or permed, its natural conditioning layer, which is made up of one tiny layer of protective fatty acids, also known as the F-layer, is removed, affecting the hair structure. The F-layer acts as a sort of raincoat for the hair strand, so when this layer is removed, hair no longer has its protective raincoat, which explains why color treated hair structures and other chemically treated hair structures soak up water like a sponge. When wet, color treated hair can increase in weight by up to 200%, whereas virgin hair increases in weight by only 12-18%. The F-layer is also responsible for keeping the cuticle smooth, which is what makes hair reflect light and shine. That’s why chemically treated hair can often look dull and drab, unless it’s cared for with a conditioning regimen designed specially to work for colored hair.

Thick or Thin?

For a single hair fiber to be deemed thick or thin depends on its diameter (the width of a circular or cylindrical object). Human hair diameter ranges from 15 microns (very thin) to 170 microns (extremely thick), with the average diameter of scalp hair being between 60 and 110 microns. Of course it’s possible to have a lot of very fine hair on one’s head, but the true determination of whether hair has a thick hair structure or a fine hair structure is its diameter - not the amount of it. The diameter of your hair has a significant impact on how you can style your hair. The thicker a hair is, for example, the more likely it is to be rigid and frizz prone. Conversely, fine hair structures tend to be straighter, far more flexible, and struggle to hold onto a created style.