Sunday, January 6, 2013

Vitamin D

   


      Vitamin D is an essential fat-soluble vitamin that is found naturally in very few foods (i.e cheese, butter, cream, fortified milk, oysters, etc.). Vitamin D promoted calcium absorption in the gut and maintains adequate serum calcium and phosphate concentrations to enable normal mineralization of bone and to prevent hypocalcemic tetany. Vitamin D also plays roles in regulation of the modulation of cell growth, neuromuscular and immune function, and reduction of inflammation. Vitamin D is found as a dietary supplement, in foods such as milk, and from sun exposure to the skin. People with darker skin tones or religious affiliations that require covering of large areas of skin (such as Islam) must be more conscious of their vitamin D intake  especially in colder seasons when people tend to stay inside more and the sun tends to be clouded over.
      If you don't receive enough Vitamin D inyour diet then you'll develop a bone disease called Rickets. It's more common in breastfed infants, older adults, people with little sun exposure, people with dark skin, people with fat malabsorption,  and people who are obese or have undergone gastric bypass surgery.  Other dieases associated with Vitamind Are osteoperosis, cancer, type 1 and type 2 diabetes , hypertension , glucose intolerance , multiple sclerosis, and others.
 
     There have been talks about how much of Serum25 D - the type of vitamin D needed to prevent deficiency- is actually needed. The Institute of Medicine concluded that the amount of Serum 25 needed to maintain is at levels ≥50 nmol/L (≥20 ng/mL). The Institute stated that 50 nmol/L is the serum 25(OH)D level that covers the needs of 97.5% of the population. Also, Serum concentrations >125 nmol/L (>50 ng/mL) are associated with potential adverse effects, such as recieving to much Vitamin D then, becoming deficient in Vitamin D when returning to regular Vitamin D levels.  
Here are the Vitamin D study results


Table 1: Serum 25-Hydroxyvitamin D [25(OH)D] Concentrations and Health* [1]
nmol/L**ng/mL*Health status
<30<12Associated with vitamin D deficiency, leading to rickets in infants and children and osteomalacia in adults
30–5012–20Generally considered inadequate for bone and overall health in healthy individuals
≥50≥20Generally considered adequate for bone and overall health in healthy individuals
>125>50Emerging evidence links potential adverse effects to such high levels, particularly >150 nmol/L (>60 ng/mL)

* Serum concentrations of 25(OH)D are reported in both nanomoles per liter (nmol/L) and nanograms per milliliter (ng/mL).
** 1 nmol/L = 0.4 ng/mL
Optimal Serum25 intake values have not been established seeing as they might change at each stage in life. The FNB established an RDA for vitamin D representing a daily intake that is sufficient to maintain bone health and normal calcium metabolism in healthy people.
Table 2: Recommended Dietary Allowances (RDAs) for Vitamin D [1]
AgeMaleFemalePregnancyLactation
0–12 months*400 IU
(10 mcg)
400 IU
(10 mcg)
  
1–13 years600 IU
(15 mcg)
600 IU
(15 mcg)
  
14–18 years600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
19–50 years600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
51–70 years600 IU
(15 mcg)
600 IU
(15 mcg)
  
>70 years800 IU
(20 mcg)
800 IU
(20 mcg)
  

* Adequate Intake (AI)

       

















More Vitamin D info here