Supplements

Vitamin D (Calcifoerol, Viosterol, Ergosterol)

Vitamin D is a fat-soluble vitamin, which also acts as a hormone. Ultraviolet sunrays act on the oils of the skin to produce the vitamin, which is then absorbed into the body. Vitamin D is measured in International Units (IU), or micrograms of cholecalciferol.

There are several forms of vitamin D, including vitamin D2 (ergocaliciferol), which comes from food sources; vitamin D3 (cholecalciferol), which is synthesized in the skin in response to exposure to the sun's ultraviolet rays; and a synthetic form identified as vitamin D5. Of the three, vitamin D3 is considered the natural form of vitamin D and is also the most active.

All three forms of vitamin D are converted into calcitriol, the active form of the vitamin, in the liver and kidney.As we age we lose the ability to synthesize vitamin D3 from the sunlight.

Vitamin D is involved in regulating the immune system and is being considered as a therapy for auto-immune disorders and to suppress rejection of transplanted organs. Vitamin D analogs have successfully been used to treat the skin disorder psoriasis; a natural vitamin D3 cream cut down on the characteristic skin flakiness.

A lack of vitamin D is one of the most frequently encountered deficiencies among people with Crohn's disease and ulcerative colitis.

Some nutrient experts think that a better absorption of calcium and magnesium improves the body's reconstruction of the protective membranes that surround nerves. Women afflicted with multiple sclerosis frequently have a low blood concentration of vitamin D3.

Women are consistently low in vitamin D which may predispose them to osteoporosis.

Vitamin D3 supplementation may reduce incidence of pregnancy-related hypertension, called preeclampsia.

Low levels of vitamin D lead to osteomalacia, a mineralization deficit of the bones, associated with osteoporosis, osteoarthritis, rheumatoid arthritis, multiple sclerosis, diabetes, heart disease, and an overactive parathyroid.

Deficiency: Rickets, severe tooth decay, osteomalacia, and senile osteoporosis.

Depleting Agents: Mineral oil, smog, barbiturates, cholesterol lowering drugs, antacids, prednisone, anticonvulsive drugs (dilantin), sedatives, intestinal disorders, liver and gallbladder disease.

Sources: Fish liver oils, fatty saltwater fish, dairy products and eggs. Also butter, cod liver oil, dandelion greens, egg yolks, halibut, liver, milk, oatmeal, salmon, sardines, sweet potatoes, tuna, and vegetable oils are sources of vitamin D. The body produces its own vitamin D when the skin is exposed to sunlight.

Herb Sources: Alfalfa, horsetail, nettle, and parsley.

Precautions: Do not take Vitamin D without calcium. Toxicity may result from taking over 645,000 IU of vitamin D over a period of two years.Signs of toxicity are unusual thrist, sore eyes, itching skin, vomiting, diarrhea, urinary urgency, abnormal calcium deposits in blood-vessel walls, liver, lungs, kidney and stomach.

Dosage Ranges and Duration of Administration: Adequate Daily Intake (AI)* is as follows:

• Infants and children: 5 mcg (200 IU)
• Adults up to age 50: 5 mcg (200 IU)
• Adults ages 51 to 70: 10 mcg (400 IU)
• Adults over age 70: 15 mcg (600 IU)

*AI reflects a level at which normal values and functional indicators of nutrition are maintained.

RDA:

• Infants up to 6 months: 7.5 mcg (300 IU)
• Children: 10 mcg (400 IU)
• Adults up to age 25: 10 mcg (400 IU)
• Adults age 25 and older: 5 mcg (200 IU)