Vitamins & Supplements

What Are the Side Effects Of Vitamin D supplementation?

effect of vitamin D

Vitamin D is mostly needed for good health as it plays role in keeping the body’s cells healthy and functioning. Supplements are common as most people do not get enough vitamin D.

Vitamin D is involved in calcium absorption, immune function, and protecting the bone and muscles including the health of the heart. It naturally occurs in food and can also be produced by our body when your skin is exposed to the sunlight. When most people do not get enough sunlight exposure to produce vitamins then the deficiency is very common.

Supplements are very common and both vitamin D2 and D3 can be taken in supplement form where vitamin D3 is produced in response to sun exposure and is found in animal products whereas vitamin D2 occurs in plants. It is possible to inadvertently consume too much vitamin D by taking supplements that contain many amounts that are listed on the label. You cannot reach blood levels at high through diet and exposure to sun alone.

6 Side Effects Of Vitamin D Supplementation

 Vitamin D Supplementation Causes Hypercalcemia

Most of the side effects that are related to vitamin D toxicity are related to hypercalcemia. It is a condition of having excess calcium in the blood as it occurs when there is more than 10,400 ng/ml of calcium in the blood. There is a strong relationship between vitamin D and calcium, when the level of vitamin D metabolites in the blood is high then this increases the amount of calcium that the intestine absorbs.

A high level of Vitamin D metabolites promotes the release of calcium from the bones into the bloodstream. Having too much calcium in the blood leads to a wide range of complication and symptoms that includes:

  • loss of appetite
  • continuous headache
  • muscle weakness
  • unexplained exhaustion
  • anxiety
  • irritability
  • joint and muscle pain
  • increased thirst and frequent urination
  • nausea and vomiting
  • confusion and disorientation
  • high blood pressure
  • reduced reflexes
  • irregular heartbeat

 Vitamin D Supplementation Can Cause Kidney Damage

Excess calcium in the bloodstream can bind with phosphate and form crystals that deposit in the soft tissues where this crystal can cause damage to the tissue. The damage of tissue depends on the eventual organ damage depending on their location or size. The kidney is especially vulnerable to calcium deposit because of its role as a filter and small passageways.

When calcium deposits get stuck in kidney tissues then it can occur nephrocalcinosis. If this condition is severe then it causes permanent kidney damage and eventually kidney failure. Its symptoms include;

  • nausea and vomiting
  • fever
  • severe pain in the stomach
  • pain in the side of the back or the groin area

Irregular heartbeat and heart attack

Extreme hypercalcemia can reduce or change the ability of the heart’s cell to function and people with hypercalcemia experience irregular heartbeat. A person with a high level of calcium in the blood may develop calcium deposits in the arteries or valves of the heart.

Some people with hypercalcemia and complete heart blockage need a permanent pacemaker. Some sign of heart complication associated with Vitamin D toxicity include:

  • chest pain
  • dizziness
  • high blood pressure
  • pain whine exercising
  • unexplained exhaustion

Brittle bones and bone pain

When there is too much calcium circulating freely in the bloodstream, the body may not have enough hormones to bind the mineral to the bones effectively where the vitamin D toxicity can cause hypercalcemia and subsequent problems. Some of them are:

  • instability
  • increase rate of falling
  • stoop posture
  • back or joint pain
  • loss of height
  • the bone that is prone to fracture


Elevated levels of calcium in the blood can harm the kidney’s ability to concentrate urine which can result in a person producing and passing unusually large quantities of urine known as polyuria. High calcium levels reduce the effects of antidiuretic hormones in which these hormones encourage the kidney to retain water and fewer hormone s may result in larger quantities of dilutes in the urine. When a person passes a lot of diluted urine then they lose large quantities of water so a person with vitamin D toxicity may be prone to dehydration.

Symptoms include:

  • Dry mouth
  • restlessness
  • irritability
  • increased thirst
  • decreased tear production
  • sunken eyes
  • dry tongue

 Vitamin D Supplementation Can Cause Lung damage

when a high level of calcium and phosphate in the blood bind to form crystals then these deposit in soft tissue where the crystals are especially like to deposit in soft tissue organ that acts as a filter. If any of these calcium salt deposits are present in the lungs they can impair the organ’s function. Some sign of the resulting lung damage include:

  • coughing
  • trouble breathing
  • pain in chest