Viamin D Toxicity Symptoms

Vitamin D is a fat-soluble vitamin needed by our bodies. We can ingest vitamin D in foods we eat, or our bodies can make it when our skin is exposed to the sun. The average population can get adequate amounts of vitamin D through their diets. Vitamin D toxicity is generally caused by taking too many supplements, which are occasionally used by those trying to optimize their calcium absorption and bone mass, as in the case of osteoporosis. The adequate intake (AI) amount for vitamin D is 200 IU (international units) daily for men and women 19 to 50 years of age, according to the Office of Dietary Supplements. The AI increases slightly for older populations. Intakes of 50,000 IU daily taken consecutively over a period of months may provide enough for toxicity to occur, Merck reports.

Nausea and Vomiting

Excessive amounts of vitamin D can have harmful effects on your appetite due to its hormone interactions. Lack of appetite is a common symptom of too much vitamin D, according to the Office of Dietary Supplements. Along with a lack of appetite, nausea and vomiting can occur. High blood pressure can be another symptom.

Kidney Issues

Vitamin D controls acid/base balance in our bodies and regulates hormones that control the kidneys. Vitamin D toxicity can cause someone to produce too much urine, a situation called polyuria. Increased thirst eventually occurs due to increased urine output. Nervousness and itchiness of the skin can also arise. If an unbalance in hormones occurs due to too much vitamin D, renal failure is a possibility. Renal failure, indicated by increased protein and wastes in the blood, can eventually cause death if vitamin D toxicity progresses.


Since vitamin D and calcium are so dependent on each other, high levels of vitamin D in the body can also cause high levels of calcium in the blood. Too much calcium can cause changes in mental status, confusion and abnormalities in the rhythm of the heart. This can be very dangerous as any changes in heart rhythm can cause severe damage.

About this Author

Jennifer Marie is a freelance writer from Cincinnati, Ohio. She has a Bachelor of Science in health and sports studies and a Master of Science in nutrition. She is currently completing her internship to become a registered dietitian.