You may have heard of DHT without really knowing what it is. However, if you are progressively losing your hair, if your part is widening, your temples are receding, and your hair density is decreasing at the crown of your head, it is probably to blame.

DHT is the hormone involved in androgenetic alopecia, the most common form of hair loss in both men and women.

What characterizes this hair loss is its slow and progressive evolution. It is not a sudden hair loss linked to stress or a deficiency, but a gradual degradation of the hair follicle itself. With each cycle, the hair becomes finer, shorter, less pigmented, until it sometimes disappears completely.

Understanding the role of DHT helps to better understand why some treatments work and why others remain limited.

 

What is DHT?

DHT, or dihydrotestosterone, is a hormone derived from testosterone. It is produced when testosterone is converted by an enzyme called 5-alpha-reductase, present in various body tissues, including the scalp.

DHT is one of the androgen hormones, involved in the development of male sexual characteristics. Men produce more of it than women, which partly explains why androgenetic alopecia is more common and more pronounced in them.

But the problem doesn't only come from the level of DHT. The genetic sensitivity of the follicles plays a central role. Two people with similar hormone levels can have completely different hair developments depending on their predisposition.

 

How DHT miniaturizes the hair follicle

Hair follicles have androgen receptors. When DHT binds to them, it triggers a cascade of biological reactions that progressively disrupt the hair cycle.

Specifically:

• the anagen phase (growth phase) shortens;

• the follicle gradually shrinks;

• each new hair becomes finer and shorter;

• the vascularization of the follicle decreases;

• the follicle eventually produces very fine, sometimes invisible, vellus hair.

This phenomenon is called follicular miniaturization.

It is this repetition of increasingly short cycles over several years that leads to the visible thinning of the scalp.

 

Androgenetic alopecia also affects women

Androgenetic alopecia is not exclusively male. Approximately 40% of women experience it during their lifetime, particularly after menopause.

In women, hair loss generally manifests differently: it is more of a diffuse thinning of the top of the head and a progressive widening of the part rather than a marked frontal recession.

The hormonal mechanism remains the same: genetically sensitive follicles react excessively to DHT.

 

Factors that worsen the action of DHT

Genetics

This is the main factor. If there is a history of alopecia in your family, it is more likely that your follicles are sensitive to androgens.

Chronic stress

Stress increases cortisol, a hormone that disrupts overall hormonal balance and can accelerate existing hair loss. Many people thus combine telogen effluvium and an androgenetic predisposition.

Nutritional deficiencies

A deficiency in iron, zinc, protein, or vitamin D can further weaken the follicles and accentuate miniaturization.

Certain medications

In some predisposed women, certain androgenic contraceptives can promote the worsening of hair loss.

 

How to act on DHT to protect follicles

Blocking 5-alpha-reductase

Finasteride and dutasteride work by inhibiting the enzyme responsible for converting testosterone to DHT.

Their effectiveness is well documented in male androgenetic alopecia, but these treatments require medical supervision due to their potential side effects.

Topical anti-DHT active ingredients

Certain molecules applied topically can help limit the action of DHT on the scalp.

Among the most studied:

• caffeine, known to prolong the anagen phase;

• Capixyl, combining a biomimetic peptide and red clover extract;

• rosemary cineole essential oil;

• Redensyl, which acts on follicular stem cells.

The objective of these active ingredients is to slow down miniaturization while stimulating follicular activity.

Minoxidil: a different mechanism

Minoxidil does not act directly on DHT. Its main role is to improve scalp vascularization and prolong the hair growth phase.

This is why it is often used in addition to anti-DHT active ingredients.

 

Can miniaturization be stopped?

The earlier the treatment, the better the chances of preserving active follicles.

A completely atrophied follicle can generally no longer produce terminal hair. However, a miniaturized but still living follicle can often be stabilized, or even partially revitalized.

The realistic goal of an anti-hair loss routine is therefore to slow down or stabilize the process before it becomes irreversible.

At HACT, the Anti-Hair Loss Serum No.1 combines 3% Redensyl, 5% Capixyl, 4% Baicapil and 0.2% Caffeine to act on several mechanisms simultaneously: support for the anagen phase, follicular stimulation and local action on factors involved in miniaturization.

Combined with the Dermastamp No.1, it also promotes the penetration of active ingredients directly into the scalp.

 

In summary: what to remember

• DHT is produced from testosterone via the 5-alpha-reductase enzyme.

• Certain follicles are genetically sensitive to this hormone.

• DHT progressively shortens the hair cycle and miniaturizes the follicle.

• Androgenetic alopecia affects both men and women.

• Treatments can slow miniaturization when started early enough.

• Topical anti-DHT active ingredients offer a local approach without systemic hormonal action.

The most important factor remains early intervention: the earlier a follicle is treated, the higher its chances of remaining active.