Regional Medical Laboratory

About Vitamin D
There has been much talk about the importance of Vitamin D levels over the last few years. Vitamin D is important because it helps the body maintain normal levels of calcium and phosphorous circulating in your blood. Vitamin D also aids in the absorption of calcium, providing a basis to produce healthy and strong bones. Vitamin D also helps regulate your immune and neuromuscular system, as well as other cellular functions.

Osteoporosis is also a very important topic as it is a skeletal disorder that is closely related to vitamin D. Osteoporosis is usually an age related disorder with the reduction of bone due to abnormal bone construction. Osteoporosis could also be due to lower bone mass production in our younger years. As we grow, bone building is dependent upon proper metabolism that is regulated by vitamin D, calcium, estrogens, androgens, and parathyroid hormone.

Vitmain D and Your Diet
Prevention of Osteoporosis is possible by maintaining a good diet. A diet that is fortified with calcium and vitamin D in our adolescent and childhood years is very a important start. By continuing a proper diet with calcium and vitamin D into our adult years, along with the avoidance of tobacco use and excessive alcohol consumption, you will be on the right path toward positive bone health. Vitamin D is only found naturally in animals and animal products; fruit and nuts contain no vitamin D at all.  Richest sources include fish liver oils, particularly those of Halibut and Cod. The best salt water fish for vitamin D are Herring, Mackerel, Salmon, Sardines, and Eel.  Traditional sources of Vitamin D are Milk, Butter, Cheese, Margarine, Cream, Yoghurt, and Egg.

Just what exactly is Vitamin D?
Vitamin D is a fat soluble vitamin called 25-Hydroxycholecalciferol (25-OH D) that is primarily manufactured by the body after exposure to ultraviolet B (UVB) rays in sunlight. Vitamin D that is synthesized in your body (endogenous) when exposed to light is known as Vitamin D3 (25-OH D3). Vitamin D that is derived from our food and daily supplements (exogenous) is known as Vitamin D2 (25-OH D2). Daily supplements are often a good idea to provide essential minerals that may be lacking in our diet.

Know your Vitamin D
Vitamin D levels are tested at our laboratory as an assessment the total volume of vitamin D2 and D3. Vitamin D Insufficiency is usually determined when the total volume of vitamin D (D2,D3) in our blood is less than 30 ng/mL. Vitamin D Deficiency is dertermined when total volume of vitamin D (D2,D3) drops further at levels less than 20 ng/mL. Vitamin D Deficiency can often progress to bone diseases such as rickets and osteomalacia. It can also be used for assessment of low levels of calcium called hypocalcemia (Low Calcium Levels). There is another Vitamin D called 1,25-Dihydroxycholecalciferol, or better known as Vitamin D 1,25-Dihydroxy (Vitamin D1-25). Vitamin D 1-25 is the biologically active form of the vitamin. Vitamin D1-25 levels are primarily used in the evaluation of renal failure and hypercalcemia (High Calcium levels) and should not be used to diagnose vitamin D deficiency.

Fun In the Sun
The good news is that studies have shown that the creation of vitamin D from normal exposure to sunlight is in equilibrium, or a feedback loop, that can prevent vitamin D toxicity. There are no recommendations by the Institute of Medicine for the amount of sun exposure needed to meet vitamin D requirements, so be careful. Excessive exposure to sunlight without proper protection could cause other problems and increase your risk of skin cancer.

Overall Health
The population of patients at risk for vitamin D deficiency are those that have a poor diet, low sunlight exposure and malabsorption syndromes. Ask your physician about vitamin D testing during your next visit. Your doctor will typically evaluate your vitamin D level in connection with your overall health and several other factors, such as medical history, age and gender.