Function
Vitamin D is used by the body for the growth of bones and teeth, improves immunity, is used for normal clotting of the blood, regulates the heartbeat and thyroid function and is involved in the absorption and utilization of the minerals such as calcium and phosphorus. Vitamin D is also used in the treatment of osteoporosis and hypocalcaemia (low blood calcium).)
Natural Sources
Butter, cheese, yogurt, milk, parsley, alfalfa, sweet potatoes, vegetable oil and oatmeal. Vitamin D is also formed by the body when the skin is exposed to sunlight.
RDA
400 iu
Deficiency Symptoms
Rickets, bone deformity, diarrhea, weight loss, insomnia.
Overdose Symptoms
Nausea, vomiting, cloudy urine, headache, irregular heartbeat, thirst, eye irritation, stomach pain and the deposit of calcium stones in the kidneys.
Interactions
* Consult your nutrition oriented doctor before supplementing with vitamin D if you have epilepsy or if you have kidney, liver, heart or blood vessel disease. * Do not use vitamin D on a prolonged basis with out medical supervision. * If vitamin D is taken with antacids containing magnesium, it is possible to have excessive magnesium absorption. * Anticonvulsants, mineral oil, cholestyramine (lipid lowering drugs), steroids and neomycin may decrease the absorption or effect of vitamin D. * Vitamin D may decrease the effect of calcium channel blockers. * Vitamin D and digoxin may increase the risk of irregularities in the heartbeat. * Thiazide diuretics and vitamin D may increase the blood calcium level, increasing the risk of toxic side effects. * Gallbladder, liver and intestinal problems may decrease the absorption of vitamin D. * Vitamin D should be taken with calcium as it increases the absorption rate.
