[ATOMIC_PUNK]

Your body can make Vitamin D in the sunlight, but ONLY if the sun is 60 degrees or more above the horizon, which is for all practical purposes, directly overhead.

That sounds like someone could only get half pregnant ..... Exposure is Exposure unless someone is referring to the Heat of the sun creating Vity D then i might buy the Quote of 60* above.

[djf]

It requires UVB radiation to make Vitamin D.

UVB is a short-wavelength ultraviolet. It doesn’t even make it to the ground if the sun is low in the sky. None of it.

A person say in Alaska could sit in the sun the entire day and make NO Vitamin D at all.

I don’t make this chit up...

[decimon]

...Exposure is Exposure...

Apparently not. The story is that Earth's atmosphere filters out the UVB rays when the Sun is low in the sky. No UVB, no vitamin D.

[djf]

http://nodivisions.com/blog/2009/09/04/Vitamin_D_Or_Youre_Not_Getting_Enough_Sun

[MediaMole]

Exposure is not exposure, since vitamin D requires UV exposure, which is cut dramatically when the sun is low in the sky.