its Vitamin D3 that you want.
i started taking D3 in the autumn, along with two 15min (had to work up to that, 10mins at first and that was almost too much) sessions on a sunbed a week. i think its made a marked difference to my general well-being this winter.
best thing about it for me is that for 15mins i totally turn off and relax, it really does feel nice just to lay in light. i can be really wound up, yet afterwards be totally stress free.
i think you’ve got to be careful with sunbeds, i can see how people quite easily damage themselves, but i like them and i never thought i would say that.
my father in law bought the bed i use, its a reasonably new semi pro quality one that he got silly cheap as a pick up only from ebay. 350quid i think.