No use for sebum / fat on the skin?

[B-Rad]

yeah exercising definitely jacks up your hormones. When I had acne problems I noticed i was more prone to breakouts when i was stressing out, lifting or having sex/masturbating.

If you live near california or have cash to spend they are opening clinics that offer new procedures which destroy your sebaceous glands. More effective than acne and permanent with no side effects

[fictor]

No side effects from destroying sebaceous glands? Somehow that does not sound right...

[B-Rad]

No side effects from destroying sebaceous glands? Somehow that does not sound right...

no not really. Currently there is no known use for human sebum and it is suspect to be an evolutionary remnant of the times when humans had fur. For example pre-pubescent children produce little or no sebum but dont have any fine lines, wrinkles or skin fragility.

[fictor]

No side effects from destroying sebaceous glands? Somehow that does not sound right...

no not really. Currently there is no known use for human sebum and it is suspect to be an evolutionary remnant of the times when humans had fur. For example pre-pubescent children produce little or no sebum but dont have any fine lines, wrinkles or skin fragility.

No known use for sebum? The sebum lubricates our skin. Also, we still have "fur". I have hears on my haid, facial hair, pubic hairs and pretty much everywhere else (chest, back, legs etc.)

[RRM]

Currently there is no known use for human sebum

So, if there is no use for sebum, why is it that primitive peoples smear fats on their skin?
Because its protective.
Modern cosmetics are based on exactly that idea.

For example pre-pubescent children produce little or no sebum but dont have any fine lines, wrinkles or skin fragility.

No wrinkles?
Have you never seen a baby?
But that aside.
Of course babies have no wrinkles caused by ageing. Not because their skin is protected despite a lack of sebum, but because they have simply not aged yet!
Wrinkles are caused when the skin loses its elasticity, after many many years. Fat / sebum on the skin prevents accelerated ageing of the skin, simply because that layer of fat is protective. Without it, the skin is dryer and sheds faster. Hence accelerated ageing.

[B-Rad]

Currently there is no known use for human sebum

So, if there is no use for sebum, why is it that primitive peoples smear fats on their skin?
Because its protective.

sure its protective. doesnt mean it prevents aging in any way though

For example pre-pubescent children produce little or no sebum but dont have any fine lines, wrinkles or skin fragility.

Fat / sebum on the skin prevents accelerated ageing of the skin, simply because that layer of fat is protective. Without it, the skin is dryer and sheds faster. Hence accelerated ageing.

Theres never really been anything to prove that. In fact everything theyve found has been almost contrary

Journal of Investigative Dermatology. 1987 Mar;88(3 Suppl):2s-6s.
"Skin lipids: an update"
Downing DT, Stewart ME, Wertz PW, Colton SW, Abraham W, Strauss JS.

Sebum and Dry Skin "...skin can be healthy and have charming cosmetic properties in the virtual absence of sebum." (14)

Kligman drew attention to prepubertal children, who produce almost no sebum, to support his thesis that skin does not depend upon sebum for maintaining its barrier to water loss: "...there can be no doubt of the insignificance of sebum as a waterproofing material." (14) Our recent studies at the other end of the human age spectrum have supported this conviction. In a survey of sebum secretion rates and the incidence of dry skin among subjects aged 65 to 97, no correlation was found between sebaceous gland activity and the presence or severity of dry skin (34). Kligman recognized that sebum could mask the scaliness of dry skin without producing any actual change in the condition: "Sebum, like any oil, has some emollient or smoothing effect when a sufficient quantity is rubbed into dry, scaling skin." (14) In spite of the clear inference to be drawn from the cutaneous characteristics of children and the experimental data obtained from the elderly, it remains difficult to dispel the myth that low sebum secretion rates cause dry skin. It is a rare individual who realizes that "dry" is not the obverse of "oily".

(14) Kligman AM: The uses of sebum. Br J Dermatol 75: 307-319, 1963

[RRM]

sure its protective. doesnt mean it prevents aging in any way though

If it protects the skin cells, it means they die at a slower pace, which means they live longer, which means that skin renewal will be exhausted less soon.

Fat / sebum on the skin prevents accelerated ageing of the skin, simply because that layer of fat is protective. Without it, the skin is dryer and sheds faster. Hence accelerated ageing.

Theres never really been anything to prove that.

you admitted that its protective (see above)

skin can be healthy and have charming cosmetic properties in the virtual absence of sebum."

Of course.
But what were we talking about?
About the protective properties of fat / sebum, not that your skin cannot be healthy without it. It will just age a little faster.
Not unimportant, i think.

there can be no doubt of the insignificance of sebum as a waterproofing material."

That is a conclusion / opinion, not a fact.
If it is a fact, where is it based on?

In a survey of sebum secretion rates and the incidence of dry skin among subjects aged 65 to 97, no correlation was found between sebaceous gland activity and the presence or severity of dry skin

Thats is not taking into account the protective nature of fat regarding ageing, as they just measure momentary sebaceous gland activity and dry skin. They have no idea how previous sebacious gland activity was in the decades before, nor how much protective skin care products were applied to the skin.

In spite of the clear inference to be drawn from the cutaneous characteristics of children and the experimental data obtained from the elderly

Thats simply rediculous. What relation is there? The skin of kids cannot tell you anything about the effects of ageing.
They just think about momentary protection / condition, and not about the effects on ageing.
There would have been inference if they would have measured skin dryness in elderly that had lacked sebum all their life. But no.

It is a rare individual who realizes that "dry" is not the obverse of "oily".

We know that. Are we rare?

[B-Rad]

If it protects the skin cells, it means they die at a slower pace, which means they live longer, which means that skin renewal will be exhausted less soon.

i thought you were referring to the physical protection of just having it on

Thats is not taking into account the protective nature of fat regarding ageing, as they just measure momentary sebaceous gland activity and dry skin. They have no idea how previous sebacious gland activity was in the decades before, nor how much protective skin care products were applied to the skin.

yeah but i think it can be safely assumed that people with high sebum output have always had high sebum output, so they shouldve possessed less wrinkles/ nondry skin

Thats simply rediculous. What relation is there? The skin of kids cannot tell you anything about the effects of ageing.
They just think about momentary protection / condition, and not about the effects on ageing.

yeah but dont you think after a few years of not having any sebum output you would start to see wrinkles/ skin dryness on kids' faces?

[RRM]

i think it can be safely assumed that people with high sebum output have always had high sebum output,

why is that?
Sebum production very much co-depends on hormone metabolism, and there are quite some changes in that throughout our life; puberty, menopause, drugs, contraceptives etc.
And there are multiple factors involved, including sun exposure, sea water exposure, the use of cosmetics etc etc etc.

dont you think after a few years of not having any sebum output you would start to see wrinkles/ skin dryness on kids' faces?

No, not at all. Small children grow so fast, and the skin has to keep up with that, which means a rapid turnover of skin cells, so that there is no time for dehydration of the skin.
Only as you get older there is a need for sebum, as the skin sheds at a much slower rate.

[B-Rad]

Sebum production very much co-depends on hormone metabolism, and there are quite some changes in that throughout our life; puberty, menopause, drugs, contraceptives etc.
And there are multiple factors involved, including sun exposure, sea water exposure, the use of cosmetics etc etc etc.

yeah but everyone experiences these things not just low or high sebum. so I dont think these independent factors would make much of a difference overall

either way i think its a tradeoff people with high sebum have generally high hormone levels causing more water retention and people with low sebum have generally lower hormonal activity retaining less water and therefore needing less sebum

[RRM]

yeah but everyone experiences these things not just low or high sebum. so I dont think these independent factors would make much of a difference overall

Thats why there are certain guidelines for scientific studies; to correct stats for such influencing factors.
VERY important, you cannot just ignore them.

i think its a tradeoff people with high sebum have generally high hormone levels causing more water retention

Its not that simple. Higher levels hormones that stimulate water retention may come with equally higher levels of hormones counteracting the water-retention influence. We simply dont know whether high sebum levels actually correlate with water retention. Thats just a hypothesis.

For the skin, ageing cells is equal to dehydration of those cells; as the outer cells lose water, they die, and vice versa. Fat inhibits that process as its hydrophobic, preventing dehydration.

[B-Rad]

no but we pretty much know high sebum correlates with high androgen levels. It just makes sense bodybuilders and athletic people most commonly get acne. one example would be like PCOS a female disease where females have extremey high test levels is always associated with mass water retention.

yes lipids prevent dehydration but sebum is only about 50% lipid content and skin oil is produced independently from sebum near the surface. So how much influence does sebum have probably minimal

[RRM]

no but we pretty much know high sebum correlates with high androgen levels. It just makes sense bodybuilders and athletic people most commonly get acne.

They also consume high protein diets...

extremey high test levels is always associated with mass water retention.

We are not talking about extremely high levels here. Extremely high levels are a malfunction / disorder. The issue is about slightly elevated levels.

sebum is only about 50% lipid content

So? thats constitutes the perfect mix, apparently.

skin oil is produced independently from sebum near the surface.

no, not independently. Acne correlates with oily skin (locally).

So how much influence does sebum have probably minimal

I dont see a connection between your conclusion and the above.

[B-Rad]

They also consume high protein diets...

Yeah but thats not all. I know plenty of people on high protein diets who bodybuild and never get acne and they all have 1 thing in common. Its hard for them to build muscle, their not usually as lean or athletic to name a few. While i know people who eat whatever they want and dont exercise that much (sometimes me) and are still leaner and more muscular. It just correlates well with my real world observations

So? thats constitutes the perfect mix, apparently.

some people with acne problems might not agree with you on that one hehe

no, not independently. Acne correlates with oily skin (locally).

skin oil cant cause acne sebum can though

I dont see a connection between your conclusion and the above.

im saying skin oil is probably more important when you're referring to lipids reducing aging than sebum is. Even though its still pretty much unknown how significant even the lipids are

[RRM]

I know plenty of people on high protein diets who bodybuild and never get acne and they all have 1 thing in common. Its hard for them to build muscle,

Sure, elevated testosterone levels are very much a contributing factor; combination of increased sebum and water retention. Elevated protein has the same effects. If you have both (and therefore easier to build muscle) you will more likely have acne.

It just correlates well with my real world observations

Ah, and im living in a ... fantasy world?

skin oil cant cause acne sebum can though

Sebum cannot by itself. Its the combination of high sebum with water retention. There are plenty of people with lots of blackheads (oxidized sebum) without acne.

its still pretty much unknown how significant even the lipids are

I thought that you claimed that lipids are not protective?
(and even that there is no use for sebum at all; nature got it wrong)