At the follicular level, the hair loss for both men and women is similar. As we talked about in a previous article, what is happening is miniaturization of the hair follicle.
In miniaturization, the normal cycle of hair growth stages (anagen, catagen, telogen, and exogen) changes and the growth phase (anagen) shortens. Instead of an anagen phase that is years long in a young person, the anagen phase gets shorter and shorter.
In addition, the tiny blood vessels and muscle attached to the follicle under the scalp become smaller and pull away. As the follicle receives less nutrition and stimulation, the hairs growing out of the follicle to become thinner, more fragile, and have a shorter life cycle before they fall out.
Eventually, as the follicle shrinks or miniaturizes, each follicle which normally grows several hairs in what’s called a follicular unit produces fewer and fewer hairs until there are none produced at all.