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Big head? Bald head! Skull expansion: alternative model for the mechanism of AGA


Big head? Bald head! Skull expansion: alternative model for the primary mechanism of AGA.

Med Hypotheses. 2009 Jan;72(1):23-8

Currently, the predominant hypothesis explains androgenetic alopecia (AGA) as a process reliant upon affected follicles being individually programmed to accumulate dihydrotestosterone (DHT), which then causes progressive follicular miniaturisation. The goal of this paper is to suggest that such miniaturisation may result from an exaggeration of the bone remodelling process causing a reduction in blood supply to the capillary network within the affected region. The bones of the human skull continue to grow during adulthood and observations made of those with AGA suggest that such growth may be responsible for the development of this condition. Studies of human cranial anatomy indicate that frontal and parietal bone growth can account for the development of the male pattern baldness (MPB) profile and the variations that can occur in the rate and location of hair loss. Steroid hormones such as DHT promote facial and body hair growth. Logically, this suggests that DHT should stimulate hair growth within the MPB region and not hair loss. However, DHT also has an anabolic effect on bone formation, and it is hypothesised that this stimulation of bone growth will overwhelm the hair growth promoting effects of DHT.

Androgen receptor sites, 5-alpha-reductase (5alpha-R) and DHT have all been associated with AGA, but they also exist within numerous types of bone cells. DHT will stimulate the proliferation of osteoblast cells and the formation of new bone. Verification of this hypothesis would imply that DHT is primarily involved with AGA through its stimulation of the skull expansion process rather than through interaction with individual follicles. Also, increased androgen receptor gene expression, 5alpha-R activity and subsequent production of DHT within the MPB region of balding individuals, may simply represent the body’s attempt to compensate for the skull expansion expression of hair follicle miniaturisation.

Furthermore, it suggests that MPB region follicles are not individually programmed for hair loss. A redirection of genetic research towards the identification of those genes responsible for skull shape and development would be appropriate, and may reveal the genetic connection to AGA including its paternal link.


This is kooky.

Head hairs are NEVER stimulated by androgens, as experiments have attested to. Hairs from people without baldness are not affected by androgens in experiments, but hairs from people with pattern baldness are negatively affected by the addition of androgen hormones.

In other experiments, the addition of high amounts of either testosterone or dihyrotestosterone can make even OCCIPITAL hair from the sides of the head regress.

Recent genetic discoveries should shed light on baldness, but mysteriously dont as weirdos still insist on coming up with oddball theories to explain it.

Basically you inherit two genes that TOGETHER make you go bald. They are one variant of the androgen receptor gene that 98.6% of all bald men have, and some gene or genes on chromosome 20 (there are 900 or so genes on chromosome 20, so it may be more than one). IF YOU INHERIT BOTH OF THESE GENES, STUDIES SHOW THAT YOU ARE SEVEN TIMES MORE LIKELY TO GO BALD.

There are a couple of more genes that have been statistically associated with pattern baldness, but clearly these two are “the biggies”.

Its not because your head is still growing. If that were so, hair transplants would not work, or would eventually fall out…and we know thats not the case.

The Journal of Medical Hypothesis is full of crap put there by yahoos who believe in alternative everything.


I agree that head expansion is bollocks.

Transplanted hair grows ok.


» I agree that head expansion is bollocks.
» Transplanted hair grows ok.

I’d not discredit this theory as fast as you did guys. It deserves some checking. So come on, do we know big heads with full heads of hair ?!


Losing hair has a habit of making the head look bigger.

Besides, Patrick Swayze has hair. Enough said.

The guy can’t even ride in a stealth bomber because his big melon alone has enough radar cross-section to get them shot down.


What about women who go for a sex change and then lose hair. Their heads/scalp did not undergo a change yet they can go bald very quickly due to the male hormones that they receive.