Hi Winkle,
Winter is over, so maybe you aren't feeling this any more - I hope you aren't. I am a newbie, so I have only just seen your post, hence the late reply.
I checked out some of the light boxes and all some of them do is provide bright light, but research would suggest that it is not just any old light you need. The hypothesis is that our Vitamin D levels affect our feeling of happiness, so that we are more likely to feel depressed when our Vitamin D levels are low. And the natural way our bodies produce Vitamin D is from the UVB rays of the sun (note: NOT UVA, which comprises the wavelengths of light which damage our skin). The artificial way of getting Vitamin D is through taking a Vitamin D3 supplement. In winter we get less sun and therefore less Vitamin D and therefore, potentially, SAD.
If I were feeling the effects of SAD, the first thing I would do would be to have my doctor check my Vitamin D levels (your doctor may not know what they should be, but you should be able to get that information from the internet). If my levels were lower than optimum, I would want to raise them before looking for other solutions. Raising Vitamin D levels is good for the immune system, even if it doesn't relieve SAD symptoms, so it is good to do anyway and could make for a healthier winter. If it doesn't work for your SAD, then look for other solutions. Let us know how you get on next winter.
