Vitamin D (calciferol), also known as the sunshine vitamin, is a fat-soluble vitamin that plays a significant role in the growth, development, and sustenance of individuals across ages. Its importance for children and adolescence requires special mention, primarily due to its role in bone mineralization (1) .
Experts recommend children and teens between the ages of three and 18 years get 600 IU (15mcg) of vitamin D per day (2) . One can fulfill this requirement by eating a well-balanced diet containing animal-origin foods and getting sufficient sunlight exposure.
Still, several children and adolescents experience vitamin D insufficiency or deficiency, exposing them to long-term health risks. So, what can parents do to ensure their children and teens get sufficient vitamin D?
Read on to learn more about the functions of vitamin D, its sources, supplementation, and dietary management. But before we begin, let’s briefly understand what vitamin D is.
What Is Vitamin D?
- Vitamin D2 (ergocalciferol): Plants and fungus synthesize vitamin D2 upon exposure to sunlight. Mushrooms (edible fungus) are excellent sources of vitamin D2. Besides, vitamin D2 is also manufactured and added to supplements and used to fortify foods.
- Vitamin D3 (cholecalciferol): Upon exposure to sunlight (UVB rays), animals and humans synthesize vitamin D3 within the body. Besides sun exposure, children and teens can get vitamin D3 from animal-origin foods, such as egg yolk, canned salmon, and dairy products.
Both vitamin D2 and D3 are inactive forms of vitamin D that need to undergo a set of metabolic processes in the liver and kidney to be converted to active vitamin D (1,25-dihydroxycholecalciferol).
Why Do Children Need Vitamin D?
Vitamin D serves several functions in the body. Here are some of the reasons why children require vitamin D (3).
- Bone growth: Vitamin D helps absorb and retain calcium and phosphorus in the body. The body requires these minerals to develop and maintain strong bones and teeth (5). In combination with calcium, vitamin D helps preserve bone mass. Children who receive insufficient vitamin D and phosphorus in their diet are at risk of developing weaker bones.
- Immune function: Research shows that vitamin D deficiency causes frequent infections and raises the risk of autoimmune diseases, such as multiple sclerosis and rheumatoid arthritis (6). Therefore, maintaining vitamin D levels in the body is vital for your child to fight infections, ward off illness, and maintain optimal health.
- Mental health: Research highlights that vitamin D regulates adrenaline, non-adrenaline, and dopamine production in the brain. If a child has chronic vitamin D deficiency, these hormones don’t act properly, leading to mental health issues, such as depression (7).Additionally, “Vitamin D has an important role in brain development and impacts learning, social development, attention and more. The brain has multiple receptors for vitamin D that contribute to nerve messaging within the body and has been shown to be connected to mental health symptoms in people of all ages,” says Courtney Bliss, a pediatric dietitian and founder of Feeding Bliss.
- Overall health: Vitamin D plays a crucial role in several biological processes and decreases the production of inflammatory substances. Clinical studies demonstrate that chronic vitamin D deficiency causes inflammation, which can cause cellular damage and also impact DNA over time (6) (8).
Moreover, vitamin D modulates several physiological processes, such as cell proliferation (increased cell numbers) and differentiation, aids nutrient metabolism, and facilitates proper nervous system and muscle functioning (3).
Sources Of Vitamin D
Children can get their daily dose of vitamin D from sun exposure and animal-origin foods and drinks.
- Sun exposure
Children can get 80% of their active vitamin D requirements from sunlight exposure (9). Therefore, spending 10 to 15 minutes in the sun with bare arms and legs a few times a week can fulfill the vitamin D requirements of most children (10). However, the amount of vitamin D a child will develop depends on several additional factors, such as the time of day, sunscreen use, and skin color. So, relying on sun exposure for a child’s daily vitamin D requirement isn’t advisable.
Note: Experts advise against extended exposure to sunlight to avert its adverse effects (11). While in the sun for long periods, children should be encouraged to wear sunscreen and take sun safety tips.
- Foods and drinks
A well-balanced diet containing various vitamin D-rich foods, such as low-fat milk, egg, and fatty fishes (salmon and tuna), can offer sufficient vitamin D to children (12). In addition to these, some other foods that can give some vitamin D to your child are vitamin D-fortified cereals and bars, fortified cooking oil, and mushrooms.
Here are some foods with the amount of vitamin D they offer (3).
|Foods||Mcg (per serving)*||IU (per serving)**|
|Cod liver oil, 1 tablespoon||34.0||1,360|
|Trout (rainbow), farmed, cooked, 3 ounces||16.2||645|
|Salmon (sockeye), cooked, 3 ounces||14.2||570|
|Mushrooms, white, raw, sliced, exposed to UV light, ½ cup||9.2||366|
|Milk, 2% milkfat, vitamin D fortified, 1 cup||2.9||120|
|Soy, almond, and oat milk, vitamin D fortified, various brands, 1 cup||2.5-3.6||100-144|
|Ready-to-eat cereal, fortified with 10% of the DV for vitamin D, 1 serving||2.0||80|
|Sardines (Atlantic), canned in oil, drained, 2 sardines||1.2||46|
|Egg, 1 large, scrambled***||1.1||44|
|Liver, beef, braised, 3 ounces||1.0||42|
|Tuna fish (light), canned in water, drained, 3 ounces||1.0||40|
|Cheese, cheddar, 1 ounce||0.3||12|
|Mushrooms, portabella, raw, diced, ½ cup||0.1||4|
|Chicken breast, roasted, 3 ounces||0.1||4|
Source: National Institute Of Health
*Mcg = Microgram
**IU = International Unit
***Vitamin D is in the yolk
Most children should meet the vitamin D needs with appropriate sun exposure and a diet containing various vitamin D-rich foods. Yet, several children have vitamin D insufficiency. Read the following sections to know who is at risk of vitamin D deficiency and the effects of vitamin D deficiency.
Factors That Increase The Risk Of Low Vitamin D Levels
- Eat only plant-based foods as they may be either vegetarians or vegans.
- Spend most of the time indoors and don’t step out in the sun.
- Cover their whole body while in the sun.
- Wear sunscreen when sitting in the sun.
- Have health conditions, such as celiac disease and cystic fibrosis that affect calcium metabolism and absorption.
- Take medications, such as anti-convulsants or those containing herbs, such as St. John’s Wort, which interfere with vitamin D metabolism and absorption.
Besides these, a child is at risk of low vitamin D levels if they have dark skin and were breastfed for an extended period and the mother was vitamin D deficient.
Note: Experts advise discussing vitamin D supplementation, especially during the fall and winter, when the sun’s rays are not at the right angle to produce vitamin D endogenously.
Effects Of Vitamin D Deficiency
- Low immunity and frequent infections.
- Muscle weakness and lethargy.
- Poor physical growth (growth stunting).
- Rickets (softening and weakening of bones), leading to bone deformities limiting a child’s movement.
- Bone pain and easy fractures.
- Hypocalcemia (low calcium levels).
- Hypophosphatemia (low phosphate levels).
Sufficient sun exposure and a diet containing vitamin D-rich foods can avert these risks. Despite these, if you suspect your child isn’t getting enough vitamin D, discuss supplement use with your pediatrician.
Vitamin D Supplementation For Children
If your child is vitamin D deficient, your doctor may prescribe them a vitamin D supplement. Vitamin D is present in multivitamins and standalone vitamin D dietary supplements available as tablets, capsules, syrups, powder, and gummies. These supplements contain vitamin D2 or D3, both of which have almost equivalent effects in raising the active vitamin D level in the body (3).
However, most pieces of clinical evidence show that vitamin D3 raises active vitamin D levels in serum to a greater extent. Additionally, it maintains high levels for an extended period compared to vitamin D2.
The types and quantities of supplements required for your child should be decided by a pediatrician. So, do not administer vitamin D supplements to your child without consultation. Doing so can increase your child’s risk of vitamin D overdose, increasing their risk of developing kidney stones (13).
It is recommended that parents keep track of the child’s total vitamin D intake from food and supplementation and keep it within the tolerable upper limits (12).
|Age (years)||Tolerable upper limit|
|1 to 3||63mcg (2,500 IU)|
|4 to 8||75mcg (3,000 IU)|
|9 to 18||100mcg (4,000 IU)|
Source: National Institute Of Health
Tips To Help Your Child Get Enough Vitamin D
Vitamin D is a vital vitamin for growing children. Therefore, follow these some simple steps to ensure your child gets their daily vitamin D requirements.
- Feed your child a well-balanced diet containing various vitamin D-rich foods, such as egg, chicken, and fatty fish, such as salmon. For vegetarian children, look for fortified cereals and dairy products. If a child is vegan, go for calcium and vitamin-D fortified plant-based foods. If you are unsure about making the right choices, consult a pediatric nutritionist or doctor.
- Make your child spend some time in the sun. Join them and indulge in physical activities, such as running, skipping, or playing badminton. Playing and exercising in the sun can get your child enough vitamin D.
However, “Be mindful of the UV index where you live and when you’re planning to go out. Limit exposure without sunscreen to 10-15 minutes each day. There are some locations across the world that will not provide adequate UV waves for creating vitamin D. Review local public health guidance for more insight,” suggests Bliss.
During sun exposure, apply sunscreen on your child’s face while leaving the arms and legs bare and without sunscreen. This is because sunscreen can reduce vitamin D production by 95% (SPF 8) to 99% (SPF 15) (13).
- Involve your child in grocery shopping. It will allow you to train them to read labels. Reading labels while purchasing is essential as not all products are vitamin D fortified. So, the next time you go grocery shopping, train them to pick foods naturally rich in vitamin D and those fortified with vitamin D.
- Test your child’s vitamin D levels at regular intervals. This is vital for children with risk factors. A child is considered vitamin D deficient if the serum concentration of active vitamin D is less than 12ng/mL (3).
- Consult a pediatrician about supplementation. Share your child’s medical and diet history with them. Also, inform them about any supplements or herbs that your child takes. These are vital, as the doctor will decide on an age-specific, safe dosage for the child only after considering these. Experts advise all non-breastfed children to take 400 IU of vitamin D supplementation if they consume less than 32 ounces of vitamin D-fortified milk per day (13).
Vitamin D is a vital vitamin that children require to strengthen their bones and teeth. Regular sun exposure for 15 to 20 minutes and eating a well-balanced diet containing vitamin D-rich foods offer enough vitamin D to most children. However, if you suspect your child isn’t getting enough vitamin D, consult your healthcare provider regarding supplement use.
2. Dietary Guidelines for Americans
3. Vitamin D
4. Vitamin D (Calcitriol); Colorado State University
5. What Is Vitamin D?; EatRight
6. Cynthia Aranow; Vitamin D and the Immune System
7. Vitamin D; Hormone Health Network
8. Vitamin D; Harvard T.H. Chan
9. Vitamin D: what you need to know; Raising Children Network
10. Time for more vitamin D; Harvard Health Publishing
11. Vitamin D: On the Double; AAP
12. Vitamin D; Fact Sheet for Consumers
13. Vitamin D Supplements: What Parents Should Know; Children’s Hospital Of Philadelphia
14. Vitamin D deficiency in children; NHS