sebaceous gland is not a relic in scalp hairs Kligman

[Armando Jose]

Q. What would happen to skin if sebaceous glands stop working?
Dr_Fulton. Probably nothing. When we were hairy like earlier on, the oil lubricate the hair like it does on the scalp. On the face, there's no hair so there's no reason for the oil glands. They're just left over as we evolved and lost hair. They don't really have any function. They just get in the way and cause impacted pores.

Dr. Fulton worked with Dr. Kligman to develop Retin A to treat acne.
So Bryan, the sebaceous gland as a relic of evolution in man with no use is refered (supossed also by Kligman) only to skin, not scalp hair.

Armando

http://www.webmd.com/content/article/1/1707_50068.htm

 

[Bryan]

I'm not sure that there's any real use for sebum in scalp hair, either.

 

[The Gardener]

Maybe gorillas with greasy fur got more pussy?

 

[Armando Jose]

Sebum is vital for a healthy hair.
Without sebum no hair.

In my opinion

Armando

 

[Bryan]

Sebum is vital for a healthy hair.
Without sebum no hair.

You keep saying that, so I'll keep asking you to explain why people with Complete Androgen Insentivity Syndrome (who produce little or no sebum) have such thick, luxuriant hair.

 

[Apoc]

I highly doubt it. Look what happens to people that take accutane: their skin starts peeling off, increased sun sensitivity etc. just because sebum stops from being produced. I think glands are very important for our skin and they protect it from aging, wrinkling etc.

 

[Bryan]

The skin peeling and sun sensitivity from Accutane has nothing to do with its sebum reduction.

 

[michael barry]

how much sebum to women have comparitevely to men?


How much sebum do children have?


We can establish a threshold of how little sebum is necessary in the least if we can demonstrate this?


We know people with androgen-insensitivity sydnrome have much much less sebum..............................so how much do they have? We can at least go "that low" and still have good hair for certain.





One more thing.......................I actually have seen a Doctor speculate on one link that sebum might be helpful from the standpoint of protecting the scalp from UV rays, especially in bald guys. Ive also read it postulated that sebum helped waterproof us to a small degree.

Do people with androgen-insensitivity syndrome have problems with sunburns Bryan? This could pretty much nail it down could it not?

 

[abcdefg]

Brian could using something like dutaseride make it more likely for someone to get wrinkles maybe prematurely? I mean DHT is found in high concentrations in the skin right? i mean its pretty much everywhere in we men.

 

[Bryan]

how much sebum to women have comparitevely to men?

How much sebum do children have?

We can establish a threshold of how little sebum is necessary in the least if we can demonstrate this?

We know people with androgen-insensitivity sydnrome have much much less sebum..............................so how much do they have? We can at least go "that low" and still have good hair for certain.

They say "one picture is worth a thousand words", so here's a scan of the graph showing sebum measurements from: "The Androgen Control of Sebum Production. Studies of Subjects With Dihydrotestosterone Deficiency and Complete Androgen Insensitivity", Imperato-McGinley et al, Endocrinol Metab 76: 524-528, 1993.

Here's some text from the body of the study which explains a little about the method they used to make those measurements, along with a few selected comments from the Results section:

Measurement of sebum production was performed with Sebutape, a hydrophobic, polymeric film that measures sebum activity through the use of air-filled micropores.....The test was performed in the following manner. The forehead of each subject was thoroughly cleansed with alcohol swabs. A Sebutape patch was placed on the forehead for 1 h. The patch was removed and the amount of sebum measured on a scale of 0-5 using reference patterns provided in the kit.. A zero (0) pattern was equal to no sebum production, whereas a a five (5) pattern signified highest sebum output. The patches were read by the investigator (LC) who was blinded to the identity of the subjects.

Results
Sebum studies

Ten normal boys and 12 normal girls between the ages of 2-6 years had no detectable sebum production by this methodology (Fig. 1), and had a sebum score of 0. Similarly, the sebum score of all adult subjects (with or without intact gonads) with complete androgen insensitivity was zero (Table 1) (Fig. 1)....

The mean sebum score for 21 control adult males was 4.4 +/- 0.6 which was significantly higher than the mean sebum score of 3.3 +/- 1.2, for 21 control adult females (P < 0.05) (Fig. 1).

The mean sebum score of adult male pseudohermaphrodites with 5a-reductase deficiency (4.5 +/- 0.6) was not significantly different from the mean sebum score of normal adult males (4.35 +/- 0.6) (P > 0.05), but was significantly greater than the mean sebum score of normal adult females (3.32 +/- 1.2) (P < 0.05) (Fig. 1).

Males treated with the 5a-reductase inhibitor, finasteride, had no significant change in mean sebum score at 6 months and 1 yr (Table 1). The placebo-treated men had no change in sebum score when tested at 6 months and after they were placed on Finasteride (5 mg) for 6 months.

One more thing.......................I actually have seen a Doctor speculate on one link that sebum might be helpful from the standpoint of protecting the scalp from UV rays, especially in bald guys. Ive also read it postulated that sebum helped waterproof us to a small degree.

Do people with androgen-insensitivity syndrome have problems with sunburns Bryan? This could pretty much nail it down could it not?

To the best of my knowledge, people with CAIS don't have problems with sunburns. And you have to keep children in mind, too, because they have similar levels of sebum production as adults with CAIS (which is very little). Has it ever been determined to what degree (if any) that children are more prone to sunburn than adults?

In any event, I want to make a general comment here: the study above clearly shows that adults with CAIS have sebum production that is close to zero, just like it is in young children. And despite the fact that adults with CAIS (and young children, for that matter) can have thick, luxuriant scalp hair, Armando continues to periodically make that silly claim that "without sebum, there is no hair". I hope everyone can now see how totally unsubstantiated that claim is. I don't know of one iota of evidence to back it up. Armando, as long as you keep saying that, I'm going to keep contradicting you!

Bryan

 

[Armando Jose]

Hi Bryan;
Thank you for your insight.

Here is a interesting studie about steroids in healthy persons before anf after puberty. Do you think prepubertal have tiny amounts of steroids?

Urinary markers of adrenarche: reference values in healthy subjects, aged 3-18 years

http://jcem.endojournals.org/cgi/content/full/90/4/2015


TABLE 2. Urinary 24-h excretion rates of DHEA according to age and sex (µg/d)

0.91 and 0.90 in boys and girls of 3 and 4 years
2,09 and 2,16 in boys and girls of 15 and 18 years


On the other hand, the results of the chart you provided are only in forehead, I would like very much see the same test within scalp with hair.

Armando

 

[Bryan]

On the other hand, the results of the chart you provided are only in forehead, I would like very much see the same test within scalp with hair.

Sebum production in the scalp is very likely to be much lower than sebum production in the forehead. You still just don't have any evidence at all that sebum is necessary for hair growth.

 

[michael barry]

thank you for that info bryan.

That settles that issue for me completely.


There are a new round of articles, started on LewRockwell.com, about the no-shampoo makes your scalp produce less oil theory starting up again. In a week or two, I imagine some of this garbage will be in the forums. It never ends.

 

[Guest]

michael, while not shampooing may not do what its advocates claim, i do know people who have not shampooed for years and their hair has not been adversely affected. i don't really see the point of shampooing myself.

 

[Bryan]

There are a new round of articles, started on LewRockwell.com, about the no-shampoo makes your scalp produce less oil theory starting up again.

I just took a look over there, and found the following statement in that "Toss out your shampoo" article:

Exposed to light and air, human skin and hair find their own balance, the oil-glands secreting just enough to protect. It is our habit of stripping this viciously from our scalps that panics the glands into overproduction---

Urban Myths die hard, don't they? Too bad they don't have a discussion forum over there...I would have presented the scientific evidence against that old chestnut of an idea.

Bryan

 

[Armando Jose]

Hi Bryan;

Well, you convinced me.

Healthy hair needs a functional sebaceous gland.
Is it better now?

Armando

Ref:
J. Anat. (1986), 144, pp. 201-220


An important feature of hair follicle maturation is the formation of the first hair canal, which is closely connected with the development of the sebaceous glands. As demonstrated by the present results in the pig, and by others in ruminants (Hardy & Lyne, 1956; Lyne & Heideman, 1959), the sebaceous gland anlage appears relatively early whereas in carnivores and the horse it remains small and inconspicuous for a longer period (Backmund, 1904; Wimpfheimer, 1907; Fechter, 1914). In man, the sebaceous gland anlage develops only after the hair bulb has totally overgrown the papilla (Pinkus & Tanay, 1968), and in laboratory animals even later (Militzer, 1982). As indicated previously, differences in sebaceous gland maturation are basically
relevant to the development of the hair follicle. But despite differences in
maturation time, structural development of the hair canal is similar in pigs, ruminants and man as shown by the present results and those of others (Goette, 1868; Hardy & Lyne, 1956; Lyne & Heideman, 1959; Pinkus & Tanay, 1968; Montagna & Parakkal, 1974; Holbrook & Odland, 1978; Dougbag & Berg, 1983b; Meyer & Gorgen, 1985 a). In all species, the hair canal is formed in two parts. The lower part develops first by disintegration of central, lipid-rich cells produced by the early sebaceous gland, followed by the keratinisation of the hair canal cells of the upper part.

 

[HARM1]

The skin peeling and sun sensitivity from Accutane has nothing to do with its sebum reduction.

HA?
SEBUM hidrates the skin and while taking accutane your lips scalp and face all become dry, how can this not be an affect of sebum?

 

[Bryan]

The skin peeling and sun sensitivity from Accutane has nothing to do with its sebum reduction.

HA?
SEBUM hidrates the skin and while taking accutane your lips scalp and face all become dry, how can this not be an affect of sebum?

First of all, sebum doesn't have any significant role in hydrating the skin.

Second of all, young children and people with Complete Androgen Insensitivity Syndrome probably produce even less sebum than patients taking Accutane, and yet THEY don't have permanently dry skin, scaling, peeling, etc. I don't believe doctors know yet exactly how Accutane works, but it obviously has other very significant effects on the structure and the function of the skin, besides just a simple reduction in sebum production.

Bryan

 

[abcdefg]

What effect do androgens have on sebum levels? does propecia or dutasteride change the level of scalp sebum at all?

 

[TA45]

sebum

Good questions! Does Finasteride eventually cause a decrease in sebum production? Since starting Propecia, I have noticed an increase in sebum production. The sebum is attaching to the end of the hair bulb, causing it 2 fall out. I attribute 100% of my hairloss to sebum. In areas where I don't have sebum, I have no hairloss whatsoever. I don't know if I should continue the Finas or not? I would really like 2 decrease the sebum production!! Feedback?-Tim