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Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

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Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#141

Post by LorenPechtel »

numpad0 wrote: post #50
csdvrx wrote: post #20

Earlier quoted context omitted.

> There is absolutely no way some translucent face painting does that. Wow what a dismissive comment to chemistry and cosmetics. Just for fun, try take a pic of yourself with a UV camera (or just UV light with some phones), and you'll see it's translucent only to the visible spectrum: https://petapixel.com/2016/05/26/tiny-uv-camera-shows-youve-...

The Sun Protection Factor(SPF) is defined "a measure of the fraction of sunburn-producing UV rays that reach the skin" when applied as instructed and only over a defined period, usually 2hr[1]. That means there is twofold difference even between a pane of glass( 1: https://en.wikipedia.org/wiki/Sunscreen#Sun_protection_facto...

This. Note that even single-layer garments generally don't have a protection factor of 100. Simply being outside in warm weather will give you more UV even if you use sunscreen perfectly--and I don't believe perfect use of sunscreen happens in the real world. I don't care how well you apply it, the protection will be degraded by movement. It will be degraded even more by touching things.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#142

Post by ttpphd »

thrown_22 wrote: post #45
freemint wrote: post #38

Earlier quoted context omitted.

IRBs look like a net detrement to most studies because they are a mechanism to prevent really bad/unethical experiments in the far tails of distribution. If those extreme studies were to happen at a non suppressed rate we would be asking for IRBs and talking how science can't regulate itself. So IRBs might be effective but they suffer from the prevention paradox.

IRBs are a net negative because really bad/unethical experiments are done with no oversight by private entities. Their only purpose is to keep ethicists employed.

I am grateful for the protection provided by IRBs and I understand exactly what kind of horrors they protect people from. They are an overwhelming positive force for good for science and society.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#143

Post by winternett »

MaintenanceMode wrote: post #89

Well, this is oddly personal for hackernews but what the heck. This is pretty interesting to me. I’ve been living outdoors for the last 12 months, and I’ve noticed some significant changes in libido. It’s been on my mind quite a bit (not only for the obvious reasons but also wondering why this is happening to me). There’s a lot of factors of course, going from a mostly sedentary indoor life to a mostly actively outdo…

I try to keep full spectrum light bulbs in as many rooms as possible within in my house, which also helps a bit, along with going outdoors as much as possible and supplementing vitamin D.

There is a whole lot of new conflict world wide out of the isolation and conservation that recent pandemics have caused. It's been a really frustrating missed opportunity by social and dating apps that they don't better help people to navigate social communication, scientifically based health advice, and relationship building/improvement with all the human isolation that is occurring and growing fast.

The term gonads though has always triggered Beavis and Butthead giggles for me ever since high school.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#144

Post by LorenPechtel »

yjftsjthsd-h wrote: post #6
derefr wrote: post #3

Implying that a primary causal factor for globally-declining birth rates could be... increased adoption of sunscreen, leading to decreases in libido? (I'm only half-joking; the countries that are most obsessed with keeping skin white — and so are likely the highest sunscreen users — are also the countries with the lowest birth rates.)

> the countries that are most obsessed with keeping skin white — and so are likely the highest sunscreen users Isn't it rather more about avoiding skin cancer?

Cultural expectations on tanning come down to signs of wealth.

Industrialized societies most work is performed indoors, most people only tan during leisure time. Thus a tan is an indication of having leisure time and is looked upon positively.

Societies that are not industrialized most work is performed outdoors, leisure is generally indoors. Thus the absence of a tan is an indication of wealth and is looked upon positively.

Note that this lags behind reality, many places have industrialized but their perception of tans is still negative. My wife is Chinese and I sometimes joke that she's half-vampire because of how sun-avoidant she is.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#145

Post by samstave »

derefr wrote: post #126
rrrrrrrrrrrryan wrote: post #30

Earlier quoted context omitted.

Being chubby and pale was desirable when the poor had to toil away outside and didn't have enough food to eat. Being thin and tan is desirable today when the poor have to toil away in offices and don't have enough free time to go to the gym or take vacations in warm places.

Being tan is desirable for the upper class , because they're trying to avoid being seen as middle class "toiling away in offices", and don't particularly care about being confused for lower class. Being pale is still desirable for the middle class themselves, though, as they're trying to avoid being seen as lower class (tradespeople, farmers, etc). Also, thinness is actually a middle-class obsession, because it's the…

>".... farmers..."

[Dystopian Aside]: I have been saying for a very long time (rightly/wrongly), but always been laughed at; "In the future, the most valuable people will be farmers"

I was laughed at.

However, look where we are headed. Right now, today ; BGates is not only one of the most famous and richest people on the oblate spheroid, he is also the richest "farmer"[0] in the world.

The "farmer" ([0]:pharm-er) who masters lab-grown civilization-supporting-scale sustenance production will be the richest in the galaxy.

Ever try to corner the galactic wheat production in Trade Wars on BBSs in the 1980s? Yeah - we are at stage zero of seeing that in action, and it wont be pretty.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#146

Post by samstave »

numpad0 wrote: post #51
rrrrrrrrrrrryan wrote: post #30

Earlier quoted context omitted.

Being chubby and pale was desirable when the poor had to toil away outside and didn't have enough food to eat. Being thin and tan is desirable today when the poor have to toil away in offices and don't have enough free time to go to the gym or take vacations in warm places.

Chubby and tan signifies strength and wealth. Thin and pale yet rich is a contradiction, adds mystique and suggests power.

Ha You physically fit, hardy to the elements, thin, muscular, used to hardship, leathered and hardened skin, emotions, grit and resentment who is only capable of using farm implements, what power do you have against me and my court of beautifully adorned elite, who weild the master-craft blades of our ancestors!? HA

'Farmer-class': Well, we have awareness, darkness, and an array of farming tools as weapons, such as Kusari Gama (sickle), nun-chuck (rice thrashers), the modern police baton is a farmers implement...

Also, we know how to fight in close quarters, such as your Rice Palace, and as such we have short, straight, nible blades and Iai KPIs show that our blades are superior in cramp enclosures, as opposed to your blades, which the curve is to assist in the blade length for the cut as you pull, however, in close quarters, your large exaggerated movements are a detriment....

Also, We know that our blade is a tool thus, we will flick dirt at you with it, because you see your sword as an extension of your soul, and will not let it touch earth.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#147

Post by sizzle »

axpy906 wrote: post #111
hh3k0 wrote: post #98

Earlier quoted context omitted.

Interesting nonetheless, thanks for sharing! Slightly related: I've decided to stop using suncreen altogether for day-to-day sun exposure. My mood and overall sense of happiness increased significantly – in fact, it seemed to have helped more than my antidepressants ever did. (My libido did not increase but my antidepressants are pretty much libido killers.)

Got to watch out with sunscreen too. Many brands have ingredients that can pass the blood brain barrier.

Shit like what??

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#148

Post by icoder »

axpy906 wrote: post #111
hh3k0 wrote: post #98

Earlier quoted context omitted.

Interesting nonetheless, thanks for sharing! Slightly related: I've decided to stop using suncreen altogether for day-to-day sun exposure. My mood and overall sense of happiness increased significantly – in fact, it seemed to have helped more than my antidepressants ever did. (My libido did not increase but my antidepressants are pretty much libido killers.)

Got to watch out with sunscreen too. Many brands have ingredients that can pass the blood brain barrier.

So has water

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#149

Post by matheusmoreira »

thrown_22 wrote: post #45
freemint wrote: post #38

Earlier quoted context omitted.

IRBs look like a net detrement to most studies because they are a mechanism to prevent really bad/unethical experiments in the far tails of distribution. If those extreme studies were to happen at a non suppressed rate we would be asking for IRBs and talking how science can't regulate itself. So IRBs might be effective but they suffer from the prevention paradox.

IRBs are a net negative because really bad/unethical experiments are done with no oversight by private entities. Their only purpose is to keep ethicists employed.

> really bad/unethical experiments are done with no oversight by private entities

Yes. For example, every time we see someone here talking about A/B testing, they're talking about human experimentation. Do these humans buy more often when shown A or B?

I consider it unethical as they don't even inform test subjects nor do they seek consent. Unfortunately, I seem to be a minority.

I don't think this argument invalidates the concept of review boards though. If anything it supports their expansion into national or international law.

Re: Skin exposure to UVB light induces a skin-brain-gonad axis and sexual behavior

#150

Post by orangepurple »

sizzle wrote: post #147
axpy906 wrote: post #111

Earlier quoted context omitted.

Got to watch out with sunscreen too. Many brands have ingredients that can pass the blood brain barrier.

Shit like what??

Zinc oxide and titanium dioxide are the only two sunscreen ingredients the FDA considers truly safe sunscreen ingredients, and as someone with a basic understanding of biology, I tend to agree with them on this (1). Zinc oxide and titanium dioxide nanoparticles refuse to penetrate the skin even when rubbed into open wounds and they have negligible effects in vivo when used topically. Additionally and crucially they block UVA, the major skin cancer promoter, which won't give you sunburns. Zinc oxide is the most effective broad spectrum sunscreen. Titanium dioxide is less effective with UVA absorption. All other sunscreen compounds function after being absorbed into the skin. Unfortunately they also get into the bloodstream where they act as hormones such as estrogen mimickers (unintentionally).

The only downside of zinc oxide and titanium dioxide is that they are awful to apply (you need a good technique) and you will probably look awful after application. It may be better to apply less material at a time but more often. Most manufacturers recommend every 80 minutes. I think this is defined by FDA regulation.

Since zinc oxide and titanium dioxide are semiconductors, they can both reflect and absorb UV. I think there is a large gap in understanding by sunscreen manufacturers of how these nanoparticles perform on a quantum level. I hold out hope that some chemist can further engineer these nanoparticles perhaps through an innovative coating to further improve performance and appearance when applied. I think there is still a lot of money being left on the table and these compounds are under appreciated, not understood well, nor developed enough to this day. Fortunately the sunscreens containing them do work today.

[1] https://www.fda.gov/media/153964/download

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