Vitamin D Lamp

I live in the UK where we get very little sun. I am so convinced of the benefits of vitamin D that I looked at purchasing a vitamin D lamp. The only serious manufacturer appears to be Spert( www.sperti.com), however the lamps are very expensive, circa $425. I called Sperti to discuss the differences between Vit D lamps and non filtered standard sun lamps. They told me that whilst they have done some tests on the effectiveness of the Vit D lamps they havent done equivalent tests on sun lamps so couldnt say if a sun lamp would be as effective in terms of how much Vit D is absorbed. They speculated that you would get Vit D from a standard sun lamp but with the addition of tanning. They also commented that as we tan we absorb less Vit D, and that the Vit D lamps dont cause tanning, from which one can extrapolate that over time you would get more Vit D from a Vit D lamp than a sun lamp.
I was contemplating trying a sun lamp, maybe even using just on the scalp, but would that be bad for the scalp?
Is tanning the scalp a good or bad thing? Do sun lamps produce UVA and UVB? Do we want to avoid UVA or acclimatise to it( see IH article ' Battling Skin Ageing and winning' - in his daily topic-http://www.immortalhair.org/apps/blog/show/1712836-battling-skin-aging-and-winning-)

The Good Ideas sun lamp, which is filtered is arounbf $70 and appears to be a safe alternative.(http://www.amazon.co.uk/Good-Ideas-Sun-Lamp-605/dp/B000WQPHIC)

I am intrigued by the use of a lamp to supply Vit D, especially directly to the scalp so would appreciate any opinions or experiences you have.
Thanks
Fib

very curious here too... i was thining of going to tanning beds this winter to make up for the lack of sun. not to tan but to stay healthy. I'm wondering if that would work to keep vit D levels up since its not natural sunlight... also how dangerous they reallly are if your only doing a couple minutes here and there and never burning or even tanning so much

Vitamin D is made when UV (more precisely, UVB rays) react with a compound (7-dehydrocholesterol) in the skin. The best rays for UV synthesis have wavelengths between 270–300 nm. Maybe you need only a 6500K lamp.