general discussion

uvb on the human skin can generate full vitamin d (calcitriol) direct

uva and longer wavelengths causes melanoma, uvb other skin cancers

uva and uvb transmission though human skin

the reasoning behind the uvb lamp i have built


at the right angles, very high cloud can magnify the vit d making rays of the sun to give good vit d at times more away from solar noon.

don't get cold sunbathing cause the immune supression will lay you open to a virus

its better to cover up in the weaker sun hours cause those rays destroy vit d in the skin

if you have an immune deficency then doing this may not be an option cause cancer is a failure of the immune system

yeah it took me a long time to work this out

skin vitamin d and oral vitamin d is a steriodal hormone and very complex in effect like vitamin d promotes a pathway making peptides which are anti-bacterial

but the short term effect of skin and oral vitmain d is amazingly immunosupressive especially from a virus point of view, though skin vit d is much more severe in this, than oral vitamin d

i think SAD has a lot to do with low vit d levels, vit d seems to only last about a month or several weeks really from when the last levels were reasonable. after a month of no vit d you can be really cacking it.

when you put the sunscreen on it blocks the vit d rays and only lets those rays through which destroy the vit d in the skin

titanium and zinc oxide, a small portion of which are nanoparticles, are used in sunscreens and god knows what is used in cosmetics as they don't list ingredients, but there could be nanoparticles !

metal based nanoparticles seem to migrate anywhere in the body, including the brain and liver !

also the uv in the sun converts some of the chemicals in the sunscreen to toxins which are absorbed

zinc oxide  generates  free radicals when exposed to uva increasing the skin cancer risk !

i have tried zinc oxide on my nose occasionally as a sunscreen, but never liked it and this may be the reason why !

benzophrene (used in some sunscreens) has hypothyroid and endometrial  propensities  !

it is better to get some intense sun exposure (without going pink at all) then cover up with clothing

vitamin d being destroyed by low height sun or sun filtered through sunscreens (uvb selectively filtered out, but oxidising uva and violet/blue permitted) is a big issue

high cirrus cloud can sometimes act like a lenses really help the vit d rays and extend the useful sun time to several hours outside solar noon

cumulus dependening on thier position can act like reflectors funneling the uvb rays as well

if the clouds are right they can give an extra 25% of uvb intensity compared to a clear blue sky

of course if they are wrong they snuff it all the way down to zero, and atmospheric moisture is also very absorbing of uvb , like up north in the australian wet season


depending where you are there is not much vitamin d rays in summer either, like north of chicago

the angle of the sun above the horizon really wants to be above 70 degrees to get a decent degree of vitamin d rays and the stratospheric ozone wants to be below about 325 dobson

my view is that the synthetic vitamin d's in supplements and put in foods as an additive are malign molecules, either the shape's not quite right or there's too many toxisterols in as well

so i built a vitamin d lamp with a broad band uvb fluorescent tube and it seems to work well enough, though you have to watch out for darkening moles

failing that if you go to a booth, ergoline range pay more attention to adequate uvb than most brands

watch out for possible herpes infection in salons, the uvb awakens the dormant virus

just remember you want to minimise tanning because melanin (the brown colour in skin) absorbs uvb and doesn't make vitamin d


the sun/ultra violet will destroy vitamin a in the skin and also depletes vitamin a in the eyes so supplementation is needed

so unless you supplement vitamin a /carotenes you will get hit with the double whammy of immune supression from the ultraviolet and vitamin d and and also the vitamin a will be below par and that will depress immune response

sunglasses can considerably reduce the depletion of vitamin a in the eyes, though a bit perhaps at the risk of upsetting the body clock

but depletion of vitamin a on the retina can be significant



so doesn't have to be converted via the liver or kidneys

so my lamp and the right sun give vit d/calcitriol direct, no wonder they have such a pronounced immediate growth effect on body muscle

297nm gives 18 times the calcitriol compared to 310nm


Novel Pathway for Hormonally Active Calcitriol

Bodo Lehmann, Peter Knuschke, Michael Meurer
Department of Dermatology, Carl Gustav Carus Medical School, Dresden University of Technology, Dresden, Germany

Calcitriol [1,25(OH)2D3], the hormonally active form of vitamin D3 (D3) is produced in both renal and extrarenal tissues. Our findings demonstrate that physiological doses of UVB radiation at 300 nm induce the conversion of 7-dehydrocholesterol (7-DHC) via preD3 and D3 into calcitriol in the pmol range in epidermal keratinocytes. The hydroxylation of photosynthesized D3 to calcitriol is strongly suppressed by ketoconazole, a known inhibitor of cytochrome P450 mixed function oxidases. The UVB-induced formation of calcitriol in human skin is demonstrable in vivo by the microdialysis technique. These results suggest that human skin is an autonomous source of hormonally active calcitriol.



“ Controversy continues both as to which wavelengths of sunlight cause melanoma and the mechanisms by which these different wavelengths act. Direct absorption of UVB by DNA is central in albino animal models, but melanin-pigmented models have shown major contributions by wavelengths longer than UVB that are thought to be mediated by photosensitized oxidant production. The only model for which the action spectrum of melanoma causation is known is a genetically melanoma-susceptible specific cross of Xiphophorus fish. We used electron paramagnetic resonance to quantitatively detect the UV induction of reactive melanin radicals in situ in the melanin-containing cells in the skin of this model and derived the action spectrum for melanin-photosensitized oxidant production. This action spectrum was identical to that for melanoma induction. These results confirm the hypothesis that melanin-photosensitized radical production is the major causative step of melanoma in this model and demonstrate that the wavelengths and mechanisms of melanoma causation in different models are dependent on the presence of melanin. This approach should be applicable to humans, thus providing an accurate surrogate for melanoma induction for prevention studies ”



they are saying 404nm to 436nm also as significant and right up to 537nm (green)

public health advice on being in the sun is probably the single biggest contributor to the increasing melanoma rate since by being out in the sun away from solar noon, the amount of uva to uvb is increased

the other big contributor was the fda mandating very low uvb in tanning booth lamps which they discreetly relaxed about 2004, very sensible of them given the burgoning melanoma rate from their dictates

uvc and uvb cleave/damage dna (uvc can form dna dimers as well i think) while uva photo-oxidises dna within the melanocytes !

interestingly uvb and uva have independent  pathways  for causing melanoma, the uva pathway involving melanin !



99%  absorption  uvb and 95% absorption uva within 300 microns or one third of a millimeter



it has a broadband uvb flourescent tube and doesn't put out much uva so it doesn't tan

the advantage of this is that you get much more conversion of the uvb into vitamin d since a tan absorbs the uvb without getting converted to vitamin d

also the latest research is showing that uva is as significant or more significant than uvb in causing melanoma , so imo its a safer way to get skin d than most sun lamps and tanning booths

in fact it can remove a tan and destroy most coloured moles, but the tan comes back with sun exposure

this is where it gets tricky, a small proportion of the moles go darker and those are the one i remove with lugols or a combination of freezing with wartner and lugols

these moles that go darker do so because they are more cancerous, that is, they are making melanin at a faster rate than the lamp is destroying the melanin so may be a way of selecting out the moles that are more likely to be a problem in later life

related links on this website are  moles,  a uvb therapy  compact lamp  for the acromioclavicular joint, and how to build a uv  weathering tester

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