Vitamin D

Vitamin D is an essential vitamin needed by our body, involved in the health of our bones, teeth, and working of our vital organs.

It influences the metabolism and availability of an important ion, calcium, in the blood stream.

Normally, this vitamin is manufactured in the body itself with the help of essential fats in the presence of sunlight. This happens in the liver.

However, in situations where enough sunlight is not available, or there is some problem with the manufacturing of the vitamin, it needs to be taken as a supplement.

How do We Know If We Are Deficient In This Vitamin?

You’ll get symptoms. Deficiency of anything important for the body express out as certain signs or symptoms. These include-

Soft bones

This is the classical symptom expressing vitamin D deficiency. The bones become soft and so bend easily.

It children, the condition is called Rickets, and is seen as bow shaped legs.

In adults, the condition is called Osteomalacia.

Muscle Pain

You may get pain in any muscle group of your body, like the calf muscles or the ankle.

You may find that your teeth are getting eroded faster.

Vitamin D deficiency may be linked to certain malignant conditions, like breast cancer, cancer of prostate or the colon. Many autoimmune conditions like multiple sclerosis, certain neuromuscular diseases are now linked with its deficiency.

How Do We Get Vitamin D?

The natural form of vitamin D is D3 or cholecalciferol.

A sun exposure of about thirty minutes twice a week is enough of vitamin D manufacture in the body. You need to take essential oils, which are required for its synthesis. These are essentially animal derived. The best source to get them is cow’s milk.

When exposed to sun, the skin surface, either your face, hand, legs or back, need to be fully exposed, without any sunscreen applied to it.

Dark skinned people need more of sunlight, as the penetration of sun rays is less through their skin. That is the reason, why they become more prone to vitamin D deficiency.

Normal Blood levels of Vitamin D

An ideal 25-OHD (25 hydroxy vitamin D) level is between 40ng/ml to 70 ng/ml.

Any level below 15 ng/ml or 37.5 nmol/l would require immediate supplementation.

Dose to be taken

  • Age 0 to 6 months- 400 IU/ day
  • Age 6 to 12 months- 400 IU/ day
  • Age 1 to 3 years- 600 IU/ day
  • Age 4 to 8 years- 600 IU/ day
  • Age 9 to 70 years- 600 IU/ day, Maximum safer upper level of intake is 4000 IU/ day
  • Age 71 years or more- 800 IU/ day


Natural Supplements

  • Vitamin D is present chiefly in animal products. You may find it in milk or yogurt, be it full fat, toned or skimmed.
  • Cheese, eggs
  • Cod liver oil
  • Mushrooms exposed to UV light to increase vitamin D. This form contains Vitamin D2 or calciferol.
  • Animal meat, containing fatty tissues.

Synthetic Supplements

Vitamin D pills combined with calcium are easily available in the market. You may take them under the supervision of a doctor, if you are deficient in this vitamin.

Sachets containing vitamin D alone, are also there in the pharmacies. The best way to take them is dissolving them in warm milk. Dosage needs to be monitored.

Drug Interactions

Vitamin D dose has to be adjusted if you are on some other medications. Tell your doctor what medications you are taking.

Some common drug interactions include that with steroid medications. If you are taking any drug like prednisolone or glucocorticoid, discuss your vitamin D dose with your doctor.

Weight loss drug, like orlistat may reduce the absorption of vitamin D. Cholesterol lowering medications also lower down the absorption of vitamin pill.

Other drugs that interact with vitamin D absorption and metabolism include thiazide diuretics, anti tubercular medicines, anti epileptic drugs, etc.

Over Dose of Vitamin D

This is common these days. In a scare to become deficient in this vitamin, people often take over dose of vitamin D.

This is dangerous and bad for the body. Our body cannot handle excess of this vitamin.

High vitamin D levels in blood gives you a constantly high calcium level in the blood stream.  This is called hypercalcemia.

As excess calcium flows in the blood, it tends to get deposited at various areas, giving rise to kidney stones, errors in the rhythm of the heart and other symptoms.

Recognizing Vitamin D toxicity

Patient present with extreme nausea or even vomiting, constipation and confusion. He may feel weak and may have frequent urination.

On examination, there may be disturbances in the heart rhythm, presence of gall bladder or kidney stones.

If not attended, the patient may get a fit or collapse due to abnormal heart beats.

What to do if you have vitamin D Toxicity?

Vitamin D toxicity presents as hpercalcemia. So treatment is, stop taking any vitamin D or calcium supplement.

If the symptoms subside in 2 to 3 hours, it’s alright. If not, you need to go to the hospital. Intravenous fluids may be infused to dilute blood.

In more sever cases, bisphosphonates or corticosteroids are given to control the calcium levels.

Medical Advice (Q&As) on “Vitamin D- How Much to Take, Over dose Management

  1. Jane


    Recently I have been feeling tired and generally unwell. I had bloods done and I am slightly iron deficient and vitamin D is borderline too.
    My question is on a day to day basis which vitamins/multivitamins and supplements would you recommend taking to keep the entire body and immune system healthy, obviously a healthy diet is important but I would really like to know about the additional vitamin supplements and the doses they should be taken in.

    1. Buddy M.D. Post author

      You need to visit your pharmacy for this. Brands differ from region to region.

      Take care not to over dose yourself. All vitamins should be within the prescribed daily limits.


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