What is it?
Vitamin D is a fat soluble nutrient comprised of two major forms; vitamin D2 (ergocalciferol) and D3 (cholecalciferol) known collectively as Calciferol. The vitamin group is fat-soluble and stable to moderate cooking temperatures. It is important for the absorption and regulation of Calcium levels in the body which helps build bones. Quantities are measured in micrograms (mcg) or international units (iu), 1mcg = 40iu. Vitamin D is obtained in fatty foods and by the action of sunlight on the skin. Vitamin D is unique among all the vitamins in that it becomes a hormone when assimilated into the body.
|Function||How it helps|
Vitamin D enhances calcium and phosphorus utilisation in the body and so has a significant impact on bone health.
|Cardiovascular health||Low levels of Vitamin D are associated with an increased risk of a cardiovasular event, as is elevated blood pressure.|
|Immunomodulation||Enables the immune system to cope more efficiently with inflammatory conditions.|
What is it used for?
|Treatment of Depression|
|Seasonal Affective Disorder|
|Cancer prevention and recovery||Vitamin D has been found to induce death of cancer cells. It also has been found to be protective against the development of cancer.|
Best food sources
|Butter||Egg yolk||Cod liver oil|
|Osteomalacia (bone thinning)||Osteoporosis||peridontal disease|
|Rickets in children||high blood pressure||tuberculosis|
|Depression||Seasonal Affective Disorder||Multiple sclerosis|
Supplementation dosage range
An upper limit of 1000iu per day is recommended unless under medical supervision. With this in mind, if you are taking food supplements including, say, Cod Liver Oil, it is advisable to add up the total units you are taking; ensure that you are under this limit and bear in mind that 400iu per day is a good level for most adults. A regular intake above 1000iu per day may cause potentially hazardous elevation in blood calcium and increased risk of excessive calcium deposition in soft tissue e.g. arterial tissue and/or the formation of kidney stones. Early signs of overdose include itchy eyes and skin, unquenchable thirst
If you have hyperparathyroidism or sarcoidosis you must consult with your doctor before supplementing with Vitamin D.
If you are taking a Calcium-channel blocking drug (e.g. Vermapril) or taking HRT medication, you should consult with your doctor before taking Vitamin D.
Vitamin D supplements should not be taken with the following drugs: digitailis, thiazide diuretics or calcitonin.
At the time of writng, there were no other well-known negative drug interactions with vitamin D.
|Factors which deplete levels, impair absorption and/or inhibit activity:|
|Fat-blocking slimming agents||Alcohol|
|Antacids containing aluminium||Barbiturates|