light box

Therapy of circadian rhythm disorders in chronic fatigue syndrome: no symptomatic improvement with melatonin or phototherapy.

Light therapy from a SADLIGHT box can only be expected to help conditions which are related to a seasonal or circadian fluctuation in severity. By providing bright light in the morning the melatonin production is stopped and this may make people who feel depressed feel a bit brighter.

this research
Vitamin D vs broad spectrum phototherapy in the treatment of seasonal affective disorder. shows that people given relatively little Vitamin D3 in Baltimore, Maryland (a lot nearer the equator than UK) had a greater improvement in seasonal depresssion than did those with light therapy.

We know from Randomized comparison of the effects of the vitamin D3 adequate that taking as much vitamin d as your body requires daily results in improved feelings of wellbeing and that such an amount is absolutely safe being less than half the proposed new safe upper limit.

Sadlight boxes work on the brightness of the light output and while full spectrum lighting may be more comfortable to sit in front of, it is the intensity of the light rather than the quality which is having the effect on the pineal gland. You have to realise that this is NOTHING to do with the Vitamin D effect from sunshine or tanning lamps which contain UVB rays which enable your skin to make vitamin D3. UVB is not part of the visible light spectrum and so any daylight simulation or full spectrum light source will not contain UVB rays (you'd have to wear sunglasses to use them if they did and that would defeat the object of the exercise)

In Vitamin d and rehabilitation: improving functional outcomes. Holick suggests that "Vitamin D deficiency and osteomalacia should be considered in the differential diagnosis of patients with musculoskeletal pain, fibromyalgia, chronic fatigue syndrome, or myositis. There is a need for better education of health professionals and the general public regarding the optimization of vitamin D status in the care of rehabilitation patients."

You can read more about Vitamin D and it's effect on health in this new paper by Holick about Vitamin D deficiency

If you still want to give light therapy a trial any bright light source will enable you to find out if you feel better using such a light. A Tasklight such as this 2D 38 watt £22.99 from Screwfix will have a similar tube in it as a SADLIGHT costing five times as much. You won't get the fancy box or timer but it will do the same job.