Vitamin D3
Vitamin D (Cholecalciferol) is a fat-soluble vitamin whose most important role is maintaining blood levels of calcium. It does this by increasing absorption of calcium from food and reducing the loss of calcium via the urine. It only allows calcium to be released from bones when levels in the blood stream are low.
Although the overall effect of vitamin D on the bones is complicated, vitamin D is necessary for healthy bones and teeth and the prevention of osteoporosis. Vitamin D may protect people from multiple sclerosis and play an important role in immunity and blood cell formation. It also helps cells “differentiate”—a process that may reduce the risk of cancer. Vitamin D is needed for adequate blood levels of insulin and supplementation may increase insulin secretion for some people with adult-onset diabetes.
The majority of vitamin D found in the body is created during a chemical reaction triggered by sunlight exposure to the skin. Therefore people with minimal exposure to sunlight and low dietary intake of foods containing vitamin D are at risk of deficiency and abnormal bone formation. In adults, vitamin D deficiency can result in a softening of the bones known as osteomalacia. In children, vitamin D deficiency is called rickets. Deficiencies are also more common in strict vegetarians, dark-skinned individuals, malabsorption conditions, hyperparathyroidism, liver disease or kidney disease, and alcoholics. Vitamin D deficiency is also very common in men with advanced prostate cancer and the elderly.
Always read the label. Use only as directed. If symptoms persist patients should consult their healthcare professional.
Dietary Sources
Cod liver oil is an excellent dietary source of vitamin D and traces are found in egg yolks and butter. The majority of body vitamin D is made through activation by sunlight on the skin.
Therapeutic Uses
- Rickets, Osteomalacia
- Osteoporosis
- Malabsorption syndromes including Coeliac's and Crohn’s disease, and Cystic fibrosis
- Alcoholics, Vegans
- Seasonal Affective Disorder (SAD)
Common and Optimal Dosage Range
People who get plenty of sun exposure don’t require supplemental vitamin D.
RDI (Recommended Daily Intake) for adults is 200 - 400 IU/day, however the beneficial amount of vitamin D is more likely to be in the range of 800–1,000 IU/day, on the basis of bone density measurements and fracture prevention in the elderly.
Cautions, Contraindications and Side Effects
- Individuals with hyperparathyroidism, sarcoidosis and kidney stones should not take vitamin D without consulting a medical practitioner.
- Too much vitamin D taken for long periods of time can lead to headaches, weight loss or failure to gain weight, and kidney stones, and rarely to deafness, blindness, increased thirst, increased urination, diarrhoea, irritability and even death.
- Doses of 400 IU up to 10,000 IU per day are considered safe for the average healthy adult. Nevertheless, people wishing to take more than 1,000 IU per day for long periods of time should consult a healthcare practitioner.
- Certain medications may interact with vitamin D. Please discuss the use of vitamin D and your current medication(s) with your healthcare practitioner.