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The LED components listed in the research aren't listed on the web site as available. In addition, DigiKey no longer appears to carry the product line...
How am I gonna build short duration dosing unit for my shower without access to these parts.
For the purposes of getting this into the public domain...
I propose a small, waterproof, battery powered device that mounts to the shower wall which directs UVB radiation at 293 uM wavelength at the midsection of the user for a timed duration when activated by the presence of water
Activation is delayed once water is detected to ensure the user is actually in the shower. The time duration is limited to ensure nobody gets cooked like Ron Popeil rotisserie.
Everything is open source because everyone needs this
Meh... just use a tube, like in the old country:
https://www.nationalgeographic.com/content/dam/photography/p...
(might be a bit nsfwish for some people)
Can confirm. This was daily routine in children's hospitals and some kindergartens. Aimed to prevent rickets. As were contrast foot baths.
Water droplets create lenses that can cause uneven exposure and possibly burns. I have had trouble sunbathing without using a towel after a swim. Just a warning before you complete your DIY project.
Moving water shouldn’t cause the same issue as stationary droplets lensing in one place.
That's something I've noticed but I think it is the chlorine mostly. Better swim at sea (if possible...)
be sure to have some eye protection in your shower too...
why 293? this fda approved product for example uses 311 (
https://www.amazon.com/Angel-Kiss-Portable-Phototherapy-Fluo...
)
Note that truly FDA-approged phototherapy devices require a prescription in the US. It's quite likely that device isn't even UVB, much less "FDA approved"
(I have a condition that requires UVb. I wasted so much money, and skin burns, on Amazon's shitty medical grey-market... )
Androv medical makes quality lights. Even though their page seems kind of shady.
Because the study says this is the most effective wavelength.
The study (open-access PDF link in the article) says that in their testing on human skin samples, the 293 nm wavelength was the most efficient, and would require 10 times less exposure to get the same effect as the 305 nm wavelength. They seem to suggest that 30 seconds of exposure with the 293 nm wavelength lamp might be the equivalent of 30 minutes of sunlight.
The PDF also says that D3 is produced from lights all the way up to 320 nm, so the 311 ones sold on Amazon would work. But given the 293 vs 305 effectiveness, how much exposure would you need to actually make a meaningful difference? Probably a lot!
Until we know that 311 nm is rather benign, we must assume that using a stronger UV source is more likely to induce cancer. While I don't know about the size of the effect here, in general you try to use the lowest possible dose when medicating.
Tangential to this topic, but Isaac Asimov wrote a book called "The Chemicals of Life" in 1954, just after Watson and Crick identified the double-helix structure of DNA. Many people don't know this, but Asimov was, at one point, a professor of Biochemistry at Boston University.
The book provides a high-level overview of the biological functions of the body and why we need certain components (essential amino acids, vitamins, minerals, etc.). Certain elements of it are dated (scientists didn't understand the purpose of cholesterol back then), but the general principles hold true.
If you're a tech-minded person who understands very little about biology, you may find the book illustrative. You can find a used copy on Amazon for relatively cheap.
I'm definitely not trying to downplay Asimov, but reading a >60 year old book to learn more about biology might not be the best use of your time. There has been an exponential (I'm not using this word lightly) knowledge gain in the last decades. The function of cholesterol won't be the only thing that's completely outdated.
I see utility in reading scientific literature produced with a vastly different outlook. What old scientists emphasized back then is worth investigating today to understand how and why they arrived at their conclusions (you know, that whole "study history to avoid repeating mistakes" spiel). Could they simply not observe the world with fine-enough detail? Where did their views derive from?
Asimov's broad strokes in here are correct, even if specific details aren't. His presentation of biological principles is lucid to a degree few can match.
In general, I agree that you're probably right. Asimov tends to be remarkably articulate though so it might be worth it (or it might not, I've never read that particular title).
Note that while older scientific materials (ie research papers, not topical sources) often have huge gaps compared to current knowledge, they are still generally impressively accurate in what they do say. Good science really does operate as a refinement process for the most part.
I could see that for a field like biology. In some other disciplines older texts weather better.
Does anyone know why humans adapted to produce D3 in skin? For mammals, we are one of the most hairless animals. Why is D3 and sun exposure so important for humans? Are there any other animals that have this requirement for health?
Warning: potential butt-speaking ahead as this is not my subject.
I have a suspicion that a lot of these things have a biochemistry that goes back a hell of a long way, and I think there's synthesis of various vitamin D's in fungi. Nearest I can find is
https://en.wikipedia.org/wiki/Ergosterol
"Ergosterol (ergosta-5,7,22-trien-3β-ol) is a sterol found in cell membranes of fungi and protozoa, serving many of the same functions that cholesterol serves in animal cells. Because many fungi and protozoa cannot survive without ergosterol, the enzymes that synthesize it have become important targets for drug discovery. In human nutrition, ergosterol is a provitamin form of vitamin D2; exposure to ultraviolet (UV) light causes a chemical reaction that produces vitamin D2"
So nothing to do with humans, and may go back to a common ancestor of fungi and protozoa.
Note the particular arrangement of the four carbon rings
https://en.wikipedia.org/wiki/File:Ergosterol_structure.svg
I believe that's a steroid. You see the same thing in
https://en.wikipedia.org/wiki/File:Testosteron.svg
and much to my surprise the same thing appears in digitalis (the foxglove plant)
https://en.wikipedia.org/wiki/File:Digitoxin_structure.svg
Which suggests these chemical families go back a very long way indeed and most likely are radiate rather than parallel (edit: I mean convergent) evolution.
Anyone who actually knows something about this, please correct or elaborate on anything.
https://www.dsm.com/markets/anh/en_US/Compendium/ruminants/v...
Looks like other mammals definitely need Vitamin D and produce it in the skin.
So 'we' didn't do it so much as some early mammal started doing it and we all inherited it.
Birds have a slightly different way of doing it but it still uses sunlight.
https://en.wikipedia.org/wiki/Uropygial_gland#Feather_and_bo...
> It has also been speculated that in some species, preen oil contains a precursor of vitamin D; this precursor is converted to vitamin D by the action of sunlight and then absorbed through the skin.
Isn't vitamin D a hormone and as such a signaling molecule, which would mean evolution could have picked any other molecule for the signaling?
That’s always bothered me. Why does our body need a signal to do things it should be doing anyway? And why did it pick something dependent on sunlight to use as a signal?
Because we weren’t meant to live in basements, extreme latitudes and dingy old people’s homes so in the face of evolution, it didn’t matter.
Why did we decide to leave warmer climates where sun was available ?
For the hardware hackers who consider building something out of LEDs for self-medical treatment, please take care to learn about UV exposure limits and evaluate both the predictable risks (skin cancer) and the unpredictable risks (e.g. pigment alteration).
I remember meeting a woman years ago, probably about 23 years old. She was very attractive with very tan skin. VERY tan skin, to the point of being like leather with wrinkles. She told me that her parents owned a tanning salon and she would use the beds whenever she felt like it.
and then... yeah. I think the risks are pretty predictable but we might have forgotten.
A young woman died in Australia recently from skin cancer due to tanning bed use. Just because the light isn’t from the sun doesn’t mean it’s safe.
Subsequently, tanning salons are now banned in Australia because of the incident you mentioned and many others.
I remember meeting a pair of 60 year old nudist ladies. Their skin was totally trashed.
And for the hardware hackers who consider building one out of a UV fluorescent tube, be aware of ozone.
uva is most harmful
If anyone ends up building lamps for themselves or buys something for self-treatment, you should look up protocols for use to treat psoriasis. Psoriasis is often treated with full-body UVB lamps like these units:
https://www.natbiocorp.com/?gclid=Cj0KCQjwreT8BRDTARIsAJLI0K...
Protocols typically start out with just 30-45 seconds, and increase from there to a max of 5-7 minutes in front of the lamps. A lot depends however on the type of skin you have, which you should figure out before starting any of this. Even though it's UVB and not UVA like at tanning salons, you can still burn yourself very badly.
There has been a lot of interest in Vitamin D on HN lately and I found this study. It may well be complete quackery, as there doesn't seem to be much discussion that I can find.
I think the 'quackery' that you are recalling could be confusion with the popular Disney movie "D3: The Mighty Ducks" [1]
[1]
https://en.wikipedia.org/wiki/D3:_The_Mighty_Ducks
I'm still ramping up on D3 and I'm trying to learn as much as I can. Do you find it helpful to supplement this Mighty Ducks movie along with a healthy diet and adequate sun exposure? Is it possible to jump straight to D3 or is it recommended to work your way through D1 and D2 first? Thanks.
Vitamin D is extremely important, affecting many areas of life. People don't realize how important until they become extremely deficient.
The question is wether it’s Vitamin D3 itself. Vitamin D3 is strongly correlated to sunlight exposure, which again is correlated to lots of other things.
Yeah... As someone with a family history of skin cancer sort of sucks that our source of D3 also comes with cancer production.
That sucks. Though skin, the tissue, is the biggest cancer risk in most humans anyway. so with most cancer and longevity reseach being focused on that there might be improvement and treatments on the way somewhere in the future.
One of those other things is nitric oxide, which is important in regulating blood pressure.
Well there are definitely some things where its causation not correlation (e.g. Rickets).
Why are there not at-home tests for various vitamin levels? Is that something that would be difficult to do? Seems like it would be a huge benefit for personal health.
Several companies offer inexpensive home blood test kits for various things including vitamin D, cholesterol, etc.
Short exposures at mid-day are best, just keep it short and avoid exposures that cause reddening of your skin:
https://pubmed.ncbi.nlm.nih.gov/18348449/
I can't find the source anymore, but it's my understanding that north of DC you need to supplement 2000IUs or 50mcg nearly half the year, and north of Mexico during Nov-Jan, as the angle of the Earth prevents adequate D production. Not to mention I often don't manage to get 15-30mins of mid-day sun, so I supplement all year round.
Wonderful. I guess all we have to do now is relocate the entire human population to areas with sufficient (but not too much) midday sun. Thanks.
Snark aside, that's obviously not practical advice at higher latitudes or during darker or rainier months.
Given the linked article is about UVB-emitting LED bulbs, an obvious solution presents itself.
Now try to order some.
Question for someone who might know, how safe are UV B lamps? IE (
https://www.amazon.com/Angel-Kiss-Portable-Phototherapy-Fluo...
) and is there a better / cheaper alternative?
The "Vitamin D Lamp" sold by Sperti is FDA approved:
https://www.amazon.com/Alaska-Northern-Lights-Sperti-Sunlamp...
It has a 5 minute timer and the instructions say to use it twice a week maximum, unless directed to do otherwise by a doctor. It has four flourescent tubes tuned to optimally emit UVB for vitamin D creation. It comes with safety goggles that have to be worn when using it. You have to stay 17" away from the lamp when it is on. Sperti says it is the only FDA approved vitamin D lamp in the USA.
It's expensive but apparently the only one of its kind at the moment, until the UVB LED's take over the market.
That is the cheaper alternative. In my experience, it's probably fake, as the FDA requires prescriptions for legitimate phototherapy devices sold in the US.
You can find the same type of devices on eBay and Alibaba for even cheaper, but those are the same "quality".
Is the HN title limited by length here? I read it, and my initial reaction is "compared to what?", since it leaves out the "Compared to Natural Sunlight" part.
Yes, it is. I edited from the original title to make it fit
I wonder if it is safe to mount simple UVB bulb at house
Here's some Soviet kids doing that, gathering around a mercury lamp:
https://duckduckgo.com/?q=soviet+uv+lamp&t=brave&iar=images&...
That... does not answer the question
No, it is not safe. Read my post above about the Sperti vitamin D lamp and it's safety requirements.
just take a multivitamin
Or you could... you know go outside.
I know it can be a struggle, but there are a lot of activities you can combine with getting outside and collect health benefits from both.
Yeah sure, I'll make sure to remember that in December when the sun is barely above the horizon even at noon-time.
I seem to remember reading that you don't get much UV light when the sun is below 40 degrees. You don't have to go far north for the sun to be kind of useless in winter.
An interesting side-note, there's a theory that Europeans are so white because the gulf-stream makes it warm enough for farming grains despite being quite far north.. and so you don't get much Vitamin D from the sun all of winter, and you don't get it from your food (like the Inuits do, from eating a lot of fish), so white skin is a "hack" to try to maxize vitamin D production, despite the obvious downsides.
Try getting enough sunlight in Seattle/Vancouver. During winter months, good luck seeing sun at all, it is all just grey sky. And when it shows up one day for a couple of hours, i have a strong feeling that even then it wouldn't be enough.
I remember 2 years ago, it was so bad, that local newspapers were celebrating when we finally got our first glimpse of sun (for a couple of hours) for that year on some day in late January (like 24th or 25th). It literally took almost an entire month to see the sun for the first time that year.
You’re describing summer in the western half of sf.
I live in Oregon, we don't get quite as much overcast as you, but we get a bunch. You still get Vitamin D from being outside on an overcast day, just have to be outside a little more.
I can believe it. Two years ago we had measurable rain every single day from December until May. I still managed to get outside and ride my bike nearly 4-5 days a week.
I just tried that but all I got was a lot of water on my head and shoulders.
Maybe somebody could push a patch to turn down the average fall-winter-spring rainfall in my area?
Not everyone has reliable/available sunlight
