Hypervitaminosis D – Vitamin D Overdose, Symptoms, Effects, Treatment

The Hypervitaminosis D is state in which your body ingests abnormally high levels of vitamin D. Although it’s not really fatal to humans the excess of vitamin d does appear to create quite many toxic effects within your body. The normal range is about 30 to 74 nanograms per milliliter (ng/mL). A few researchers claim that an adult human can take 250 µg (10,000 IU) a day to remain in a safer zone. In this article we are going to discuss toxic levels of vitamin D as well as effects of vitamin D overdose along with its symptoms and treatment.

Hypervitaminosis D

Effects of Vitamin D Overdose – Vit D Overdose Side Effects

According to researchers, there are probably long-term effects of vitamin D overdose. Most people believe that if you expose yourself to the sunlight for far too long you’re likely to intake excess vitamin d. That is not quite true since the vitamin D precursor, cholecalciferol likely regulates the vit d overproduction.

During your continuous exposure to sunlight the vitamin D precursors which are born in the skin reaches the equilibrium state only to alleviate the vitamin D overproduction. They just destroy any extra vitamin D production in your skin. However people having melanin pigmentation in the skin are vulnerable to hyper vitamin D.

Medical practitioners do recommend taking an oral dose between 250 µg and 625 µg (10,000 IU and 25,000 IU) each day provided they are fully exposed to sunlight.

  • The excess of vitamin D likely produces calcitriol concentrations not only in cell but in plasma too.
  • The vitamin D toxicity also produces plasma calcifediol concentrations which overcome the binding ability of vitamin D-binding Protein (DBP).
  • The vitamin D intake also produces the concentration of vitamin D metabolites.
Hypertension Irritability
High Blood Concentrations of Calcium Decreased Appetite
Soft TissuesFatigue Vomiting
KidneysMuscle Weakness

Studies indicate that lipoprotein particles carry dietary vitamin D into the cells of the atherosclerotic and artery wall. The monocyte-macrophages convert vitamin D into active form. Perhaps now researchers are beginning to concern about the effects of vit D on cardiovascular risk as well as atherosclerotic calcification as it likely causes vascular calcification.

Read More: Hypervitminosis

Patients who have high intake of vitamin D are less likely to develop vascular calcification for they protected by vitamin D analog, alfacalcidol.

According to studies the vitamin D status in Indians is pretty low in spite of the fact that the sunshine occurs all throughout the year in India.

hypervitaminosis D
Chemical structure of cholecalciferol, aka vitamin D3.

Foods Rich in Vitamin D

  • Beef liver
  • Egg yolks
  • Fatty fish
  • Mushrooms
  • Cod liver oil
  • Cheese

Hypervitaminosis D Treatment – Vitamin D Toxicity Treatment

Many researchers agree that the vitamin D toxicity isn’t really caused by the excessive exposure to sun or diet—it occurs due to megadoses of vitamin D supplements. The reason behind is that when you take in vitamin D from the sun your body tends to regulate it. The fortified foods do not seem to contain excess vitamin D.

When your body contains calcium in your blood (hypercalcemia) in excess it gives rise to the vitamin D toxicity. Let’s now discuss some of the vitamin D toxicity treatments.

  • In order to avoid vitamin D toxicity you can stop taking dietary calcium.
  • Your family doctor may prescribe you some medications such as bisphosphonates and corticosteroids.
  • Studies suggest that if you take high vitamin D doses more than that recommended by Recommended Dietary Allowance (RDA) you’re likely to develop toxic levels of vitamin D. The toxicity is primarily caused by taking in 60,000 international units (IU) a day.

References & Further Reading

Freedman BI, Wagenknecht LE, Hairston KG, Bowden DW, Carr JJ, Hightower RC, Gordon EJ, Xu J, Langefeld CD, Divers J (March 2010). “Vitamin d, adiposity, and calcified atherosclerotic plaque in african-americans”The Journal of Clinical Endocrinology and Metabolism95 (3): 1076–83.

Scientific Advisory Committee on Nutrition (2007) Update on Vitamin D Position Statement by the Scientific Advisory Committee on Nutrition 2007.

Fraser DR (April 1983). “The physiological economy of vitamin D”. Lancet1 (8331): 969–72.

Tuohimaa P (March 2009). “Vitamin D and aging”. The Journal of Steroid Biochemistry and Molecular Biology114 (1-2): 78–84.