Is Hair Loss Reversible?

If a hair follicle stops producing hair, does that mean it is permanently ‘dead’?

In androgenetic alopecia, the most prevalent form of hair loss affecting men and women, affected hair follicles progressively shrink, through a process known as miniaturisation. While this results in the production of finer and shorter hairs, dormant and miniaturised hair follicles retain stem cells which has the capacity for hair regeneration, and can still respond to effective treatments that stimulate hair regrowth.

Left untreated however, prolonged androgenetic alopecia can eventually progress to irreversible follicular changes. One structure that has been studied in relation to hair loss is the role of the arrector pili muscle (APM).

The arrector pili muscle is attached to the hair follicle bulge, which contains stem cells required for hair growth and hair follicle regeneration. The APM-bulge connection persists throughout the hair growth cycle and has been suggested in studies to play an important role in morphogenesis and renewal of hair follicles.

In the early stages of hair loss, miniaturisation begins in the secondary hair follicles, as the arrector pili muscle detaches from regressing secondary follicles.

As hair loss progresses, the miniturisation continues and the arrector pili muscle detaches from primary follicles as well. Once the arrector pili muscle fully detaches from all secondary follicles and primary follicles in a follicular unit, hair loss often becomes irreversible.

It is not always possible to determine whether a follicle can still produce hair simply by looking at the scalp with the naked eye. A clinical assessment involves examining the hair loss pattern, duration of hair loss, and a trichoscopy, which uses a magnified device to examine the scalp in detail.

Signs of irreversible follicular loss that we look out for during assessment include:

• Smooth, shiny patches on the scalp (resembling scar tissue)
• No visible pores/follicular openings
• Absence of vellus hairs (fine, light-coloured hairs) at the affected area
• Prolonged duration of hair loss, with no new hair growth for over two years at the affected area

The Importance of Treating Hair Loss In Its Early Stages
Treating hair loss in its early stages not only improves the prognosis but also provides one with more treatment options. Non-invasive options, such as hair growth lasers are among proven treatments that can help with hair restoration in suitable patients. However, once a hair follicle has been permanently lost, a hair transplant would then be the only option for hair restoration.

For this reason, it is generally advisable not to wait until an area progresses to complete baldness before seeking treatment. Early intervention can help determine whether the hair follicles are still viable and identify the appropriate treatment options.

Have more questions on hair loss or thinning? Reach out to learn what options may be suitable for you.