Vitamin D: The Sunshine Vitamin for Growing Kids

Let’s explore why this nutrient is important, where to find it, and how much your child needs. Ensuring your child gets enough Vitamin D is essential for their growth and development, but it’s not just about soaking up the sun.

What is Vitamin D?

Vitamin D is a fat-soluble vitamin necessary for proper calcium absorption and bone growth in children and adults. Very few foods naturally contain vitamin D; most Vitamin D used by our bodies comes from production in our skin.

Thankfully, severe Vitamin D deficiency is now rare. However, it can still occur in populations with low sun exposure, limited access to fortified foods, or genetic malabsorption syndromes. The primary biological action of Vitamin D is to promote calcium absorption in the intestines, making it vital for building strong bones and teeth.

Why is it important for growing children?

Vitamin D is important for children to enable healthy bone growth. Without enough Vitamin D, the body struggles to absorb calcium and phosphorus, the main building blocks of strong bones and teeth. Without sufficient Vitamin D, children may develop weak bones or, in severe cases, deformities such as Rickets.

Common Sources of Vitamin D

      1. Sunlight Exposure

• Skin synthesis is the primary natural source of Vitamin D.

• Even a few minutes of sunlight exposure to the face and arms can provide the equivalent of 200 IU of Vitamin D daily.

• Factors like season, cloud cover, and time of day can affect Vitamin D production in the skin. Prolonged sunlight exposure does not lead to toxic levels.

      2. Dietary Sources

• Natural Sources: Fatty fish, like salmon and trout, are rich in Vitamin D, though the content varies between species.

• Fortified Foods: In North America, products such as milk, baby (infant & toddler) formula, and breakfast cereals are often fortified with Vitamin D.

Daily Requirements

The recommended daily allowance (RDA) of Vitamin D for Infants aged 0-12 months is 400 IU daily. Those living at northern latitudes may require up to 800 IU daily.

For children aged 1-18 years, the recommended daily intake is 600 IU. Outside of sun exposure, the intake can be via dietary choices or a supplement. 

If you feel that you are receiving adequate exposure without covered skin (around 10-15 minutes/day) or sunscreen during summer months, you may only require supplementation during late fall, winter or early spring seasons (for example, October to May) when sunlight is more limited.

Living at Northern Latitudes 

At northern latitudes, there may be inadequate solar radiation to facilitate Vitamin D synthesis, particularly during the winter months. If you and your child live in northern latitudes with limited sun exposure, it is particularly important to provide your child with vitamin D supplementation and fortified foods. 

Breastfed vs. Formula-Fed Infants

• Formula-Fed Infants: Most infant formulas are fortified with Vitamin D.  However, additional supplementation may still be needed.
  
  
• Breastfed Infants or those receiving Breast Milk: Breast milk contains low levels of Vitamin D, so infants receiving breast milk should receive Vitamin D supplementation.

If you have concerns about vitamin D intake for your child, it may be important to discuss these with a healthcare professional to determine your child’s individual needs.

     Kathryn Holt 
     Registered Dietitian
     Lakeside RD, Custom Nutrition and Counseling
     https://lakesidecustomnutrition.com/