"It is often difficult to determine how much vitamin D supplementation is needed to obtain the “sweet spot.” For these reasons, you should routinely get your vi

"It is often difficult to determine how much vitamin D supplementation is needed to obtain the “sweet spot.” For these reasons, you should routinely get your vitamin D levels tested and rely on dietary sources or supplementation to boost your levels when necessary." http://blog.wellnessfx.com/2013/08/14/the-vitamin-d-sweet-spot-and-its-relationship-to-aging/ http://blog.wellnessfx.com/2013/08/14/the-vitamin-d-sweet-sp...