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Other Names:
Cholecalciferol, Vitamin D3, Ergocalciferol, Vitamin D2

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There are many known benefits to Vitamin D supplementation:


Vitamin D’s is principally used in preventing and treating Osteoporosis. Patients who have severe osteoporosis often have low levels of vitamin D. It is widely known in the medical community that Vitamin D induces calcium absorption and is good for bone health however Calcium and Vitamin D use must be uninterrupted. Improvements in bone density rapidly disappear once the supplements are stopped.. In a 2-year, double-blind, placebo-controlled study of 65 individuals with rheumatoid arthritis taking low-dose corticosteroids, daily supplementation with 1,000 mg of calcium and 500 IU of vitamin D reversed steroid-induced bone loss, causing a net bone gain. Vitamin D supplementation offers an important advantage to patients suffering from osteoporosis: research has found that when older individuals take Vitamin D supplements, they have less tendency to sway while standing or walking and this may reduce their chances of falling. Since the most common adverse consequence of osteoporosis is a fracture due to a fall, this is a significant benefit.

Those concerned about osteoporosis should take Vitamin D-Calcium supplementation as it definitely helps prevent bone loss, even if you are taking other treatments for osteoporosis. It is relatively simple to understand that you cannot build bone mass without Calcium and Calcium cannot be absorbed and used without adequate concentration of Vitamin D. Supplementing with vitamin D alone may or may not be helpful, but the combination of calcium and vitamin D has been found to slow down or even reverse the progression of osteoporosis.

A one year long, double-blind study of 249 postmenopausal women with an average age of 61, none of whom were taking estrogen or other medications for bone loss was conducted in Boston, a city that gets little sunshine during winter months. Half of the women received a Calcium Citrate malate supplement (400 mg daily) plus a Vitamin D supplement (400 IU daily), and the other half received placebo. The women who took the Vitamin D-Calcium combination experienced a 0.85% net increase in spinal bone mass, whilst the placebo group showed no net change. Another double-blind, placebo-controlled study of 3,270 women found higher dosages of vitamin D produced even better bone density increase results. For a period of 1.5 years, participants received either placebo or 1,200 mg of calcium and 800 IU of vitamin D. The scientists found that the bone density in the hips of women who had taken Vitamin D-Calcium combination supplement had increased by 2.7%, while the hip bone density of the women who had taken placebo decreased by 4.6%. The Vitamin D-Calcium supplement taking group also experienced 43% fewer hip fractures.

2 Recent research has found that Vitamin D helps maintain a healthy immune system.
3 Vitamin D has also been proposed for use in: Cancer Prevention. There is some evidence to support the theory that adequate intake of vitamin D may help prevent breast cancer, colon cancer, cancer of the pancreas, prostate cancer, and skin cancer.
4 Vitamin D has also been proposed for use in prevention and reducing the risks of developing Diabetes and Hypertension.
5 Vitamin D may fight inflammation and prevent gum disease. The American Journal of Clinical Nutrition, September 2005 issue, reported that people with higher blood concentrations of vitamin D are less likely to develop gum disease and that the higher is your Vitamin D concentration, the lower the risk of gingivitis, a milder form of gum disease in which the gums become swollen and bleed easily after bacteria build up between the teeth and gums. The anti-inflammatory benefit of Vitamin D may explain vitamin D's link to healthier gums.
6 Vitamin D is used in treatment of Psoriasis. Danish studies use calcipotriol, a variation of vitamin D3 applied externally to the skin to treat Psoriasis. It must be noted that Calcipotriol does not affect the body's absorption of calcium, and it is a very different substance from the Vitamin D supplements you find in drug stores and pharmacies.
7 Some healthcare providers use Vitamin D for treatment of Seasonal Affective Disorder ("the winter blues"). There is weak evidence to support this.
8 A study suggests that Vitamin D-Calcium supplementation may be helpful for women with polycystic ovary syndrome.

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Dosages of vitamin D are usually expressed by the number of international units (IU) rather than in milligrams. U.S. and Canadian health authorities recommend different daily intake dosages of vitamin D for different age groups, as follows:

Infants 0–12 months 200 IU (or 5 mcg)
Males and females 1–50 years 200 IU (or 5 mcg)
Males & Females 51–70 years 400 IU (or 10 mcg)
Males & Females 71+ years 600 IU (or 15 mcg)
Pregnant women 200 IU (5 mcg)
Nursing women 200 IU (5 mcg)

There is growing evidence that these dosage guidelines are too low, particularly if you are sun-deprived. Those who live in cities with little sunshine are at increased risk of Vitamin D deficiency. For example, in a study conducted in Denmark, it was found that in veiled Muslim women, a daily intake of 600 IU of vitamin D was insufficient to raise vitamin D levels in the blood to normal levels and some have suggested that sun-deprived individuals receive 1,000 IU of vitamin D per day.

For therapeutic purposes, higher dosages of Vitamin D can be taken, but only under the care of a qualified physician or knowledgeable health care provider.

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The foods we eat everyday contain very little Vitamin D. Exposure to the sunlight provides the highest levels of Vitamin D but most dermatologists recommend that you limit direct sun exposure to no more than 10-20 minutes a day or otherwise use sun-block to prevent skin disease and certain types of cancer. These lifestyle changes and sun-blocks may be increasing the frequency of vitamin D deficiency. Cold water fish are the best food sources of Vitamin D. In many countries, manufacturers add Vitamin D to dairy products, cereals and milk and margarine. Severe vitamin D deficiency was common amongst sailors who spent most of their days under deck rowing or amongst miners. Cod liver oil, which is high in vitamin D, became a popular supplement to help prevent rickets in children. Those who had rickets were deficient in Vitamin D and presented symptoms of soft bones that curved in day to day normal use simply because they could not absorb adequate calcium.

In modern times, Vitamin D deficiency often occurs amongst the elderly who receive less sun exposure.

Also people who live in the northern latitudes and don't take adequate vitamin D supplements are more likely to suffer from diseases linked to deficiency of Vitamin D. They display increased risks of osteoporosis, hypertension, cancer and brittle bones.

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There is evidence to suggest that Vitamin D-Calcium supplementation can help protect against bone loss caused by corticosteroid drugs such as prednisone. A recent review of five studies showed that Vitamin D-Calcium supplementation can significantly prevent bone loss in corticosteroid-treated patients.

Do not take high-dose vitamin D (with calcium) unless you have been advised to by your physician. If you take Thiazide diuretics, do not take calcium and vitamin D supplements unless under doctor's supervision.

There are many medications on the market which may interfere with vitamin D absorption or activity. These include the blood-thinning drug heparin; corticosteroids; primidone (Mysoline), valproic acid (Depakene); phenytoin (Dilantin), Phenobarbital for seizures; Cimetidine (Tagamet) for ulcers and the anti-tuberculosis drugs Isoniazid (INH) and Rifampin. Ask your doctor whether you should take extra Vitamin D.

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Vitamin D