[incrudible]

Not exactly. However, I've been taking Vitamin D for a while now and I can't say that feel "more refreshed".

[shock]

I would guess that it depends on what your current vit D level is. Also, depending on your genotype you might be a fast or slow metabolizer of vit D, which would also play a role in how big of a dose you would need.

I recommend the talks/interviews by Dr. Stasha Gominak a neurologist specializing in sleep.