Dr. Robert Heaney Speaks on Vitamin D in Calgary on September 19, 2012

Dr. Robert Heaney delivers a speach on Vitamin D and its protective effects against multiple sclerosis and other diseases. Dr. Heaney was introduced by Carole Baggerly of Grass Roots Health

A new survey says a lot of Brits never go out in daylight in winter.

https://uk.lifestyle.yahoo.com/millio...112310193.html

Tired all the time but no mention anywhere about the how their low vitamin D levels will be making them tired, or the need fror supplementation.

The lack of exposure to bright light is associated with Circadian Rhythm disturbance.
It can be treated with BRIGHT LIGHT THERAPY.
With bright light exposure switching OFF melatonin production during the day and so allowing a greater production of melatonin at night.
It's actually different from Vitamin D deficiency although the two are related.
There are some studies showing REPLETION of Vitamin D status was more effective than SADLIGHT therapy in resolving Seasonal Depression.

There has been a recent study showing
Study is first to find significant link between sleepiness and vitamin D deficiency

Humans are supposed to produce VITAMIN D from dawn to dusk and MELATONIN from dusk to dawn. We are so smart we prevent Vitamin D by wearing clothes, staying indoors, using sunscreen when outside and we prevent melatonin by using bright light at night, street lighting, digital displays, shift working and so on.
And then we wonder why we are ill and get cancer.