A deficiency in Vitamin D can be absolutely debilitating to your immune system in addition to causing a host of bone problems. Lack of vitamin D reduces your body's ability to absorb calcium. Taking adequate amounts of Vitamin D can improve your ability to absorb calcium by as much as 40%. If you want to learn more about the benefits and side effects of Vitamin D, check out the following blog post with a video by Dr. Rhonda Patrick on the Joe Rogan show: Vitamin D Benefits and Deficiency Effects - Sun and Supplementation
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