Vitamin D Overdose in Children

Vitamin D is a fat soluble vitamin and is essential for the healthy functioning of the body. It plays a major role in absorption of important minerals like calcium and phosphorus in body which in turn keep the bones and muscles healthy. Deficiency of vitamin D can lead to rickets in children that has an adverse effect on the growth and development of the child. It can lead to bone deformities. However, an overdose of this vitamin is also not good for children. The condition of vitamin D overdose is termed as hypervitaminosis D.

How Can a Vitamin D Overdose Occur in Children?
The main cause of too much vitamin D in children is excess intake of vitamin D supplements. The requirement of vitamin D in human body is quite low. The maximum amount needed is produced by the body itself with the help of sunlight. Daily exposure to sunlight for 10-15 minutes is enough to produce adequate amount of vitamin D. So, the daily requirement of vitamin D from various food sources is not more than 5 micrograms or 200 IU. So, we can say that children do not need additional supplements.

Vitamin D deficiency commonly occurs in those children who are suffering from rickets or children who do not have the ability to absorb vitamin D from food sources due to some health disorder like kidney problems. They are given supplements is in order to counter the effect of lack of this vitamin in their body. Depending on the condition of the patient, the exact dosage is ascertained. The maximum limit of daily dosage of vitamin D supplements recommended for children are as follows:

• Babies below the age of one: 1,000 IU
• Toddlers below 4: 2,500 IU
• Children in between 4-8 years: 3,000 IU
• Children above the age of 9: 4,000 IU

If the dosage of vitamin D is increased beyond this limit without consulting the doctor, then children can have an overdose. Similarly, if the recommended dosage is continued for several months without monitoring the levels of vitamin D in the body, then it can lead to overdose. In other words, one single overdose of vitamin D supplement does not cause toxicity. Rather, it develops over a period of time. As this vitamin is not soluble in water, the body cannot excrete out the excess amount of vitamin. The extra vitamin D gets stored inside fat cells and reaches toxic levels.

How to Recognize Vitamin D Overdose in Children?
Excess of vitamin D in a child's body can have an adverse effect on the digestive health and weaken the overall health. A few identifiable signs and symptoms of vitamin overdose are given below:

• Constipation
• Nausea
• Vomiting
• Diarrhea
• Dehydration
• Unexplained weight loss
• Weakness in muscles
• Headache
• Fatigue
• Irritability
• Nervousness

If the treatment for vitamin D toxicity in children do not start on time then it can start affecting the functioning of the vital organs of the body like heart, lungs and kidneys. As a result, children may develop heart disease, lung problems and renal failure.

Treatment
When children are taking vitamin D supplements and show one or more of the overdose symptoms mentioned in the previous section, then they should be taken to the doctor. The condition is diagnosed with the help of blood test and urine test. The supplement intake is stopped immediately. Even the calcium intake of the child is minimized. Doctors often recommend a low calcium diet in this condition which should be continued for several weeks. If the level of vitamin D is too high, corticosteroids may have to be administered to reduce it. In serious cases, when there are signs of dehydration observed, patients are hospitalized and intravenous fluid is administered.

Finally, I would like to clear one thing that over exposure to direct sunlight also does not cause vitamin D overdose in children. This is because when the body absorbs vitamin D from sunlight, its production stops naturally once the body has enough vitamin D. On the other hand, when vitamin D enters the body from a supplemental source, the body cannot stop absorption of the vitamin.