Also known as: Vitamin D (cholecalciferol), Vitamin D3 (as Cholecalciferol)
Fat-soluble vitamin that facilitates calcium absorption in the gut and maintains adequate serum calcium levels in the body. Vitamin D is needed for bone growth, bone remodeling, cell growth, neuromuscular and immune function, and reduction of inflammation.
What Is It?
Vitamin D is a fat-soluble vitamin (along with A, E, and K) and is one of the 24 micronutrients required for basic human survival. The primary way to intake vitamin D is through direct exposure to sunlight, but it can also be consumed by eating various types of fish, as well as eggs.
Vitamin D Deficiency
The human body synthesizes vitamin D from cholesterol provided that there is an appropriate amount of UV light from sun exposure. However, many individuals are simply not out in the sun long enough or frequent enough for this to occur due to working long hours or simply remaining indoors far too often.
This has led to a chronic deficiency in Vitamin D among the population and has necessitated that the vitamin be consumed in supplement form. Of the various forms that Vitamin D comes in, individuals should look forVitamin D3 (cholecalciferol) as opposed to D2 (ergocalciferol), since D3 is used more effectively in the body.
What Does It Do?
Vitamin D is essential for maintenance of bone mineralization through the regulation ofcalciumandphosphorushomeostasis, as well as bone formation and density.Vitamin D also supports many of the non-skelteal systems in the body, particularly the immune, endocrine, and cardiovascular systems.
Chronic deficiencies in this crucial vitamin have known to lead to the development of conditions like rickets, osteomalacia (softening of bones), osteoporosis, and muscle weakness.
Vitamin D is also crucial for the body's production of testosterone. Clinical studies have documented a link between low/deficient vitamin D levels and testosterone levels. Therefore, if you notice your libido slipping or having trouble making gains in the gym, it may be worth increasing your Vitamin D intake.
Recommended intake set by the Food and Nutrition Board is approximately 600 IU/day for adults. Intakes as high as 3,000-5,000 IU / day have shown to be safe without any adverse side effects.