Fine and thin hair are often words that are used interchangeably. They however mean different things and knowing that difference can help you pick the right products for your hair.
The difference between fine and thin hair
What do we mean by fine hair?
Fine hair is referring to the diameter of each fiber. How narrow or how large it is, is characterized by terms such as fine, medium or coarse. Typically fine hair is around 40 μm in diameter as compared to coarse hair which can be as thick as 100 μm in diameter. In fact fine hair can barely be felt when rubbed between the fingers.
What do we mean by thin hair?
Here we are referring to the density of hair on the whole head. People with less follicles have less hair fibers which translate to a lower density of hair (thin hair). Similarly, people with diminished follicle activity (less growth), will have a decrease in their hair density often referred to as thinning hair. Thinning hair is the term used as hair loss begins.
Now that we understand the difference between fine and thin hair, it is easier to picture that hair can be both thin and coarse (low density but thick fibers) or that dense hair can consist of fine hair fibers.
It is usually an assumption that someone with a thick set of locks probably has coarse hair. But now we know that this is not necessarily the case. In fact growing up, I was often told by various hairdressers that my hair was terribly coarse and dense just because it had a huge volume (from being frizzy all the time). It turns out that my hair is in fact at a medium point for both thickness and density.