Vitamin D Depletion
While it has long been assumed that the majority of the population achieves adequate levels of vitamin D through exposure to the sun, the biosynthesis of the nutrient is affected by time of day, seasons, location, smog/pollution, clothing and sunscreen. In addition, those with darker skin require more exposure to the sun to attain adequate levels. These factors all contribute to the insufficiency seen in a growing portion of the population. It takes about 48 hours for vitamin D to be absorbed from the skin into the body and washing skin during that time period can interfere with absorption into the blood. Inadequate intake or levels of cholesterol can also inhibit the adequate production of the nutrient. Depleted levels of vitamin D may interfere with the normal development of teeth and bones, normal cell growth, and contribute to poor regulation of immune and nervous systems. Certain medications have been found to contribute to deficiency of vitamin D, including some anti-seizure medications, bile acid sequestrants, oral corticosteroids, and weight loss medications, which bind fats.
Bone and Dental Health
Numerous studies have highlighted the importance of vitamin D to maintaining healthy bone density. In one 2013 study, 52 overweight men and women with suboptimal vitamin D levels were given either 7,000 IU of cholecalciferol daily or a placebo for 26 weeks. The vitamin D group significantly increased vitamin D levels in the blood and improved biomarkers of bone health.
Cardiometabolic Health and Blood Sugar Balance
In light of the role that vitamin D plays in a variety of tissues and body systems, it comes as no surprise that much research from recent years has underscored its contribution to cardiometabolic wellness. There is accumulating evidence that calcitriol helps strengthens cardiomyocyte function, vascular smooth muscle cells, and the vascular endothelium.
Immune Health and Modulation
One of the more profound functions of vitamin D is its ability to modulate immunity. An important recent study suggested that improving vitamin D status significantly affects the expression of genetic pathways linked to immune activity. Vitamin D has been shown to boost the immune response by up regulating specific genes that increase cellular production of natural compounds that protect us against pathogens.
Numerous studies also point to the key role of vitamin D in supporting musculoskeletal strength and comfort. In one study, among 62 adult patients with nonspecific musculoskeletal discomfort, over 95% had vitamin D deficiency and responded to replenishment of vitamin D. Moderate deficiency of vitamin D has also been shown to predict knee discomfort over a fiveyear period and hip discomfort over two years.
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Always be sure to speak with your healthcare provider before starting any new nutritional supplement when pregnant or nursing. For children, we recommend speaking with your child's pediatrician regarding proper dosing. Store away from children.