What about vitamin D toxicity?
It is impossible to generate too much vitamin D in your body from sunlight exposure: your body will self-regulate and only generate what it needs. Although very rare, it is possible to overdose and become toxic with supplementation as vitamin D is a fat soluble vitamin and therefore stored in the body for longer periods of time. Therefore if you are taking 5,000 IU or more daily, you should have your blood levels monitored approximately every 3 months.
Dr. John Cannell MD, the Executive Director of the Vitamin D council stated in a recent Vitamin D Council on-line newsletter http:// www.vitamindcouncil.org/vitaminDToxicity.shtml entitled ‘The Truth About Vitamin D Toxicity' that there is no evidence anywhere in the published literature that even 10,000 IUs per day of vitamin D is toxic to humans and that human toxicity does likely not occur until over 40,000 IUs of daily consumption. "Vieth reports human toxicity probably begins to occur after chronic daily consumption of approximately 40,000 IU/day (100 of the 400 IU capsules)." He goes on to state that "Physician ignorance about vitamin D toxicity is widespread" and concludes by stating that "In fact, living in America today while worrying about vitamin D toxicity is like dying of thirst in the desert while worrying about drowning."