Vitamin D is an essential, fat-soluble vitamin that has evolved as a hormone helping normal bone mineralization, proper nerve and muscle functioning, and immune system regulation (1). According to the dietary guidelines for Americans (2020-2025), children and teens between the ages of three and 18 should consume 600 IU (15mcg) of vitamin D each day (2).
Children can get their daily dose of vitamin D by sun exposure and intake of various foods, such as fortified milk and fatty fish. Yet, it is estimated that one in every ten US children is vitamin deficient (3). Vitamin D deficiency in children increases the risk of several health issues that could affect the quality of life.
This post tells you about the causes, symptoms, complications, and treatment of vitamin D deficiency in children.
Sign And Symptoms Of Vitamin D Deficiency In Children
The symptoms of vitamin D deficiency develop when the body’s vitamin D levels are quite low. The symptoms could vary depending on the severity of the deficiency. Below are some of the common signs and symptoms of vitamin D deficiency in children.
- Fatigue and tiredness: Low vitamin D levels in the body could trigger fatigue (4). Research has highlighted that vitamin D deficiency can weaken bones and muscles, making an individual prone to tiredness. These symptoms usually resolve upon vitamin supplementation (5).
- Generalized muscle pain: Vitamin D regulates muscle functions, and its deficiency is associated with muscle pain (myalgia) (6). However, how vitamin D deficiency causes muscle pain is still under research. An animal study proposed that vitamin D deficiency stimulates the pain-sensing nerves in the muscles (7).
- Frequent infections: Research demonstrates that vitamin D deficiency can modulate innate and acquired immunity, raising the risk of autoimmunity (8). Enhanced autoimmunity puts an individual at risk of autoimmune diseases and recurrent infections, especially of the respiratory tract (9) (10).
- Impaired wound healing: Research shows that vitamin D has vital anti-inflammatory properties, which can hasten wound healing (11). A clinical study also demonstrated that vitamin D promotes the production of compounds necessary for the wound-healing process (12).
- Bone loss: Vitamin D facilitates calcium absorption, which mineralizes the bones and teeth. In severe vitamin D deficiency, the body’s calcium absorption decreases, and the parathyroid hormone levels increase, triggering calcium loss from bones. Due to the combined effect of reduced calcium absorption and increased bone loss, children develop nutritional rickets. Rickets is a condition where the bones soften, resulting in painful bone deformities that affect life quality (13).
In growing children, bone loss and muscle weakness could severely affect daily activities, such as walking, playing, and climbing stairs.
Possible Causes Of Vitamin D Deficiency In Children
The following factors and conditions could lead to vitamin D deficiency in children.
- Vitamin D deficient diet: Most foods don’t contain vitamin D, and it is why vitamin D fortification has become vital. However, several children, especially picky eaters, don’t get the required amounts of vitamin D even from fortified foods, increasing the risk of deficiency.
- Limited exposure to sunlight: Vitamin D, also known as the “sunshine vitamin,” is produced by converting the inactive vitamin D (cholecalciferol) to its active form (calcitriol) when the skin is exposed to UVB (ultraviolet B) rays. Children usually get 80 percent of their active vitamin D from sunlight (14). However, those who spend most of their time indoors or wear sunscreen while playing outside are at vitamin D deficiency risk.
- Cross-interaction with medicines: Corticosteroids and anti-seizure drugs are certain medications that may lower vitamin D levels in the body (15). If your child or teen is on any medication, consult your healthcare provider or doctor. They are most likely to suggest a supplement, especially if the child’s vitamin D levels are already insufficient or low.
- Physiological problems: Certain conditions, such as abnormal liver and kidney functions, cystic fibrosis, inflammatory bowel diseases, and celiac disease, could lead to poor absorption of dietary vitamin D by the body. It may gradually lead to vitamin D deficiency.
Diagnosis Of Vitamin D Deficiency In Children
A doctor will order a blood test to measure 25-hydroxy vitamin D levels in the body. Below is the representation of the vitamin D status based on its serum levels in nanograms per milliliter (ng/mL) (1).
|Vitamin D status||Levels (ng/mL)|
|Severely deficient||Less than 12|
|Insufficient||Between 12 to 20|
|Sufficient||Greater than or equal to 20|
Source: National Institute Of Health
Treatment Of Vitamin D Deficiency In Children
Treatment for vitamin D deficiency involves addressing the cause of deficiency and providing supplementation. The supplementation will include intake of vitamin D tablets or mixtures that the child has to either take daily (low dose) or weekly or monthly once (high dose). The dosage depends on the cause of the deficiency and the overall health of the child.
If your child is already consuming a multivitamin or is on any medication, inform your doctor so that they can adjust the dosage accordingly. Additionally, they will advise you to add vitamin D and calcium-rich foods to the daily diet with 15 to 20 minutes of sunlight exposure a few days a week or daily.
Possible Complications Of Vitamin D Deficiency
Untreated vitamin D deficiency may increase the risk of the following conditions.
- Hypocalcemia (low calcium levels)
- Hypophosphatemia (low phosphate levels)
- Poor physical growth and development
- Severe bone deformities limiting a child’s movement
How To Prevent Vitamin D Deficiency In Children?
Optimum sun exposure and eating a well-balanced diet containing vitamin D-fortified and calcium-rich foods, such as fortified milk, breakfast cereal, and cheese, are sufficient to prevent vitamin D deficiency.
|Food||Vitamin D content (IU) in 3.5oz. (100g)|
|Fresh salmon (wild)||600 – 1000|
|Fresh salmon (farmed)||100 – 250|
|Shitake mushroom (fresh)||100|
|Shitake mushroom (canned)||1600|
Note: 1IU vitamin D = 0.025mcg (micrograms)
Source: American Academy of Pediatrics (AAP)
If you are unsure about your child’s vitamin D intake, consult a pediatric nutritionist who may provide a diet plan to treat and mitigate vitamin D deficiency in your child.
Vitamin D deficiency is a health concern, especially for children who are still growing. Depending on the extent of deficiency, a child may exhibit various symptoms, such as general weakness, fatigue, and frequent infections. Speak to a doctor to determine the underlying cause. Timely vitamin D supplementation can prevent long-term complications, while adequate vitamin D intake and sunlight exposure can prevent vitamin D deficiency in children.