Frequently Asked Questions About Vitamin D

What is Vitamin D?
Vitamin D is one of the essential vitamins your child needs for healthy bone development. A healthy level of vitamin D in the body helps regulate calcium and phosphorus levels for bone formation. Vitamin D is fat soluble and is naturally produced when your child’s skin is exposed to sunlight without sunscreen.  Vitamin D is also a prohormone, which means that it is converted into a hormone inside the body. Vitamin D prevents rickets in children. New research is showing that vitamin D may also help in a variety of diseases including osteoporosis, cancer, multiple sclerosis, heart disease, psoriasis and Alzheimer’s disease.

Why is it important for my child to get enough daily vitamin D?

A healthy level of vitamin D in your child’s body helps proper bone development. Without enough vitamin D, the bones can soften and become deformed. This condition is known as rickets. Although not common anymore in developed countries, many children across the world still develop rickets due to poor nutrition and lack of sunlight. Since vitamin D is converted into a hormone inside the body, it is now believed that vitamin D also affects the immune system, nervous system and heart health.

How much daily vitamin D is required for my child?
Although each child is different, the generally accepted daily vitamin D requirement for young children is 400 IU. This is the amount provided by 4 cups of milk or 10-20 minutes of sun exposure without sunscreen depending on the skin type, geographical location and the time of the year. Most experts now believe that this level is not enough especially for at-risk children such as those with dark skin, overweight or obese, or with other health issues. Consult your pediatrician for a specific recommendation.

How do I know my child is vitamin D deficient?
Visible signs of vitamin D deficiency are rare in the developed countries since rickets in children are not very common. Another problem is that experts do not agree on the definition of vitamin D deficiency, especially in young children. You can evaluate your child’s risk by reading the article 5 ways to tell if your child has a vitamin D problem on Littlestomaks.com. If you believe that your child may be at risk, ask your pediatrician for a blood test which will accurately show the level of vitamin D in your child’s body. Your pediatrician can then assess if your child may be deficient in vitamin D.

What foods should my child eat to get a good amount of vitamin D?

Very few foods are natural sources of vitamin D. Fatty fish such as salmon, mackerel, tuna and sardines are very good sources of vitamin D. Milk is nearly always fortified with vitamin D. Other vitamin D fortified products are orange juice, yogurt and breakfast cereals. Cod liver oil as a supplement can also be used. Foods listed under various meal types in the vitamin D calculator are all good sources of vitamin D.

My child is very healthy and active. Should I still be worried about vitamin D deficiency?

It is very difficult to tell if your child is vitamin D deficient simply by the overall health and activity level. In most cases, there are no obvious signs of vitamin D deficiency anymore since children in the developed countries generally do not develop rickets. The only way to be certain that your child is not deficient in vitamin D is by a blood test. As described in 5 ways to tell if your child has a vitamin D problem, your child may still be at risk depending on his/her diet, skin type, geographical location and other health issues.

What are the symptoms of vitamin D deficiency?
Unless there is an extreme situation, there are usually no external signs of vitamin D deficiency. In those rare cases of extreme vitamin deficiency, your child may complain of bone and muscle pain and show signs of bone deformity such as bowing of the legs and swelling of the wrist. Health conditions such as obesity, diabetes, heart disease and malabsorption disorders are linked to vitamin D deficiency. Children with vitamin D deficiency sometimes show low weight gain, impaired growth and respiratory issues. It is best to consult with a pediatrician who can confirm vitamin D deficiency by a blood test.

If my child is getting the daily recommended amount of vitamin D, can he/she be still deficient in vitamin D?
Since vitamin D needs to be absorbed by the body and processed by the kidneys into its active form, it is still possible for your child to be deficient in vitamin D even if he/she is getting enough from the diet.  Malabsorption disorders such as liver disease, cystic fibrosis, Crohn’s disease, Whipple’s disease and Coeliac  disease can result in poor absorption of vitamin D from diet and sunlight.

What is the difference between vitamin D2 and vitamin D3?

Vitamin D2 and D3 are two forms of vitamin D. Vitamin D2, also known as ergocalciferol is derived from plant and fungal sources such as mushrooms by ultraviolet light treatment. Vitamin D3, also known as cholecalciferol, is derived from animal sources. Vitamin D3 can be made by exposing skin to ultraviolet light or exposing milk to ultraviolet light. Both vitamin D2 and D3 are converted by the body to the same biologically active form. Vitamin D3 is about 2-3 times more effective than vitamin D2. If you don’t see vitamin D3 specifically mentioned on the food label, assume that it is all vitamin D2.

Is there a problem with too much vitamin D?
It is impossible to get too much vitamin D from food or sunlight exposure. Overdose of vitamin D can occur from nutritional supplements or pharmaceutical grade vitamin D. Typically chronic levels of 50,000 or 100,000 IU per day are required to cause hypercalcemia, a condition in which there is an excessive amount of calcium in the blood. Hypercalcemia can have a variety of health disorders such as anorexia, nausea, vomiting, calcification of soft tissue including the kidney, blood vessels, heart and lungs. Pregnant women should consult with a doctor before taking a vitamin D supplement. In general, nutritional supplements including vitamin D supplements should not be given to young children except under special circumstances and with professional supervision. In general, young children should not get more than 3000 – 4000 IU per day of vitamin D.

How do I know that vitamin D from foods my child eats is actually absorbed by his/her body?
The only way to be completely sure is by a blood test to determine the level of vitamin D absorbed by your child’s body from different food. The blood test measures the amount of 25-hydroxy-vitamin D, which is the circulating form of vitamin D in the blood. Your pediatrician can advise you on when and how frequently you should get your child’s blood tested for vitamin D.

How much of the vitamin D from foods, sunlight and supplements is absorbed by my child’s body?
Each child is different, therefore the actual amount of vitamin D absorbed from food and sunlight can vary. In general, a daily level of 400 IU from food is considered sufficient for children without known risk factors and health disorders. The only way to ensure that your child has enough vitamin D in his or her body is by a blood test. Most healthy children with a balance diet and an active lifestyle will grow up to develop a normal ability to absorb sufficient vitamin D from diet.

Does vitamin D interact with any other medications my child might be taking?

Yes, vitamin D can interact with other medications such as steroids, certain weight loss and cholesterol lowering drugs. Check this article on WebMD for more details. Consult with your pediatrician about your specific situation.

Which vitamin supplement is best for vitamin D?
In general, young children should not be given vitamin supplements. Supplements are not tightly regulated by the FDA and their quality may vary considerably between different brands. Although not many foods naturally contain vitamin D, it is possible to have your child get adequate vitamin D with proper diet and outdoor play. There are situations where you may consider a multivitamin for your child but you should treat vitamins as drugs and consult your pediatrician before using them. Here is a detailed review of some of the common multivitamins for kids.

We have plenty of sunshine where we live and my child loves to play outside. Should I still worry about vitamin D deficiency?
There are many reasons to still think about your child’s vitamin D levels even if you get plenty of sunshine all year around. Chances are that you make sure your child has plenty of sunscreen all over before stepping out to play in the sun. There is good reason for that because you hear so much about skin cancer from over exposure to the sun. The problem is that even a low SPF rated sunscreen blocks out ultraviolet rays from the sun, which is the absolute requirement for production of vitamin D in the exposed skin. That is why sun exposure with sunscreen does not help at all when it comes to getting a healthy dose of daily vitamin D.

How does my child’s skin type affect his/her vitamin D level?
Skin color is another important factor which determines how much vitamin D your child is able to get from sun exposure. Skin color is a result of melanin, a pigment which protects the skin from the ultraviolet rays by delaying the onset of a tan or sunburn. Darker the skin, less is the amount of ultraviolet energy available to make vitamin D. That is why children with dark skin are at risk of vitamin D deficiency even if they happen to spend a lot of time outdoors. Fair skinned children readily absorb the ultraviolet energy but also risk getting a sunburn sooner. There are 6 different skin types based on sun sensitivity. Type 1 is most sensitivity to sun and burns easily while type 6 is least sensitive.

What is the difference between natural and synthetic vitamin D?
Chemically there is no difference, although your perception may depend on how you define natural. The most natural form of vitamin D is produced in the skin when it is exposed to the sun. This is how nature intended us to get a sufficient dose of vitamin D on a daily basis. Another natural way of getting vitamin D may be from wild fish such as salmon which are naturally rich in vitamin D. When vitamin D is added to foods during processing, such as fortified milk, cereal or other processed food, it may be considered non-natural or synthetic. Again, chemically speaking there is no difference between natural and synthetic vitamin D and both are processed in the same way inside the body.

Is there an “organic” vitamin D?
We live in a world where the word organic has become a popular word with a lot of buzz. Strictly speaking, it refers to the way foods are processed before they are brought to the market. If no chemical fertilizers, pesticides and insecticides are used while growing plant based foods (fruits, vegetables etc.), then they can be certified as organic. Animal products are organic if the animals are raised on organic feed. Since vitamin D can come from both animal and plant based sources, it will depend on how the source materials are grown or processed. I have yet to come across an organic label on vitamin D, but don’t be surprised if you see it in future. Always be aware of false claims and look for a certification from a credible organization.

Why does use of sunscreen prevent my child from getting vitamin D from sunlight?
Sunscreen contains chemicals which prevent the sun’s ultraviolet rays from penetrating the skin. The SPF rating or the sun protection factor is a measure of the effectiveness of a sunscreen in blocking the UV-B rays from causing a sunburn. Even a low SPF sunscreen can block enough UV-B from reaching the deeper layers of the skin so that the reaction which converts skin cholesterol into vitamin D cannot occur. Using sunscreen therefore prevents your child from getting a sunburn, but completely shuts down the vitamin D production in the skin.

How long should I let my child stay out in the sunlight for vitamin D without getting sunburn?
It depends on your child’s skin type, the local UV index based on your geographical location and how much of the skin is exposed to the sun. The vitamin D calculator provides an estimate of the time it would take for sunburn based on these factors.

How accurate is the vitamin D calculator?
There are many factors which affect the accuracy of the daily vitamin D calculation based on food and sunlight exposure. Vitamin D value of different foods is based on an estimate provided by the USDA. The amount of each food consumed by your child is entered by you after each meal. Amount of vitamin D from sun exposure is estimated by the local UV index which is a forecast by the weather service. The overall accuracy of the daily calculation depends on these factors.

When should I talk to my doctor about my child’s vitamin D level?
You should talk to your pediatrician about your child’s vitamin D level at a regular wellness visit. You should discuss this matter in detail if your child has the risk the factors for vitamin D deficiency such as dark skin, vegetarian diet, not much sun exposure, milk allergy or sensitivity, obesity or overweight. You should also talk about it if you have a family’s medical history such as heart disease, cancer and malabsorption disorders may add to your child’s risk factors. When in doubt, address this issue early on so your pediatrician can assess your child’s risk and order appropriate tests.

Can I request a vitamin D blood test for my child?
Yes, especially if you suspect your child may be at risk due to poor nutrition, lack of sun exposure and other health conditions. A blood test is the only way to confirm if your child may have vitamin D deficiency. Ask your health insurance provider if blood test for vitamin D is covered.

{ 1 comment… read it below or add one }

John Franks January 27, 2013 at 7:07 am

I have been low vitamin D almost 2 years. I am being treated by an Endocrinologist at Kaiser. I am unable to take D supplements of any kind including fish oils. Doing so causes sedation, impaired balance, headache, nausea, swelling in mouth, forgetfulness, increased muscle – joint pain. Eat lots of food containing D. Avoid fortified food/fluids with D. Last week began UVB 5minute full body sessions every other day at tanning salon. Will appreciate any useful suggestions you may have. Thanks, John Franks


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