Science

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When scalp perimeter muscles contract, even lightly, they create a tensile pattern across our scalps that perfectly matches the patterning and progression of AGA.
Involvement of Mechanical Stress in Androgenetic Alopecia

Some studies show DHT is anti-inflammatory.
Androgens modulate the inflammatory response during acute wound healing

In the prostate, DHT helps regulate inflammation
Antiinflammatory effect of androgen receptor activation in human benign prostatic hyperplasia cells

And most importantly, this study demonstrated that the TGF-β family can over-express in scalps versus bearded regions.
Identification of Androgen-Inducible TGF-β1 Derived from Dermal Papilla Cells as a Key Mediator in Androgenetic Alopecia

This study showed that TGF-β1 increases in the presence of DHT.
Induction of transforming growth factor-beta 1 by androgen is mediated by reactive oxygen species in hair follicle dermal papilla cells

Studies show that transforming growth factor beta 1 (TGF-β1) encourages the onset of calcification.
Transforming Growth Factor-β1 Mechanisms in Aortic Valve Calcification: Increased Alkaline Phosphatase and Related Events

This study showed that TGF-β1 actually encourages perifollicular fibrosis.
Perifollicular Fibrosis: Pathogenic Role in Androgenetic Alopecia (PDF)

Men and women who take androgens (steroids) significantly increase their risk of arterial calcification
Androgen-induced progression of arterial calcification in apolipoprotein E-null mice is uncoupled from plaque growth and lipid levels

The relationship between age and calcification doesn’t really exist. Calcification doesn’t have to increase with age. It can be rampant in young adults and nearly absent in older ones.
Chapter 5 - Calcification: A Physiologic Defense § Aging and Vascular Calcification

Balding regions have 40% lower oxygen levels versus non-balding regions.
Transcutaneous PO2 of the scalp in male pattern baldness: a new piece to the puzzle

Blood flow is restricted in scalp regions with thinning hair.
Subcutaneous Blood Flow in Early Male Pattern Baldness (PDF)

In studies done in test tubes, an increase in androgens doesn’t cause calcification.
Androgen receptor-dependent transactivation of growth arrest-specific gene 6 mediates inhibitory effects of testosterone on vascular calcification

As fibrosis accumulates around a hair follicle, it expands into the hair follicle shafts, constricting the room a hair follicle has to grow hair.
Characterization of inflammatory infiltrates in male pattern alopecia: implications for pathogenesis

And as this collagen accumulates, it eventually turns into scar tissue — known as perifollicular fibrosis.
Androgenetic alopecia and microinflammation

Balding men have four times the amount of collagen fibers at the temples and vertex than men with zero hair loss.
Dermal fibrosis in male pattern hair loss: a suggestive implication of mast cells

In balding scalps, chronic inflammation persists until fibrosis sets in
A hypothetical pathogenesis model for androgenic alopecia: clarifying the dihydrotestosterone paradox and rate-limiting recovery factors

TGF-β1 is probably best-known as a substance that can cause fibrosis, calcification, and skin-related aging.
TGF-β in aging and disease

Studies show that transforming growth factor beta 1 (TGF-β1) encourages the onset of fibrosis.
Adenovector-mediated gene transfer of active transforming growth factor-beta1 induces prolonged severe fibrosis in rat lung.