No other aspect of human development` in children is as immediately associable with their ‘growing up’ quite like the way they get taller. While it’s not the only factor in the equation, the primary impetus for their increasing height is bone growth and development, and particularly in the femur bones of the legs.

Most of us are too young to have ever either heard of rickets or had it be a threat to their bones, but rickets was a degenerative condition that was prevalent in the 19th century where Vitamin D deficiencies caused people to have bowed legs as those same femur bones grew without the proper nutrients required to do so straight and true.

Very thankfully, we now live in a day and age where nutritional deficiencies of such severity are very uncommon, and accordingly – as mentioned – you may well have never even heard of rickets. But suffice to say, a certain level of Vitamin D and calcium are required for children and teenagers to have their bones grow and develop properly.

As regards calcium, ensuring that children’s dietary calcium needs are being met will allow them to reach their natural height and stature potential and make it so that their bodies are able to stand up to the rough n’ tumble nature of young lives that is common for most kids. For girls in particular, getting enough calcium is very important as the extent to which they meet those requirements in childhood and youth is implicitly related to whether or not they will be at risk of osteoporosis or bone disease much later in life, according to Brenda Somina, a pediatric nutrition counselor working in conjunction with YesWellness.

So today we’ll expand on what we’ve just introduced briefly – why are calcium and vitamin D so important for a child’s growth?


To get the basics out of the way, we’ll start by providing basic guidelines for calcium intake for different age groups.

1 – 3 years old: 700mg (milligrams) of calcium daily

4 – 8 years old: 1,000mg of calcium daily

9 – 18 years old: 1,300mg of calcium daily

Calcium requirements are highest during puberty and adolescence, due to accelerated muscular, skeletal, and endocrine development. Further, mineral deposit and retention in bones is very much dependent on the dietary absorption of calcium. By the time a child reaches 17, almost 90% of their adult bone mass will be in place.

Calcium’s benefits stretch beyond bone structure, however. It’s also very important for a child’s developing heart, nerves, and internal organs working properly. Calcium helps to regulated muscle function and the contractions of the heart, serves to allow thorough transmission of nerve impulses, and helps with proper blood clotting (and boy oh boy do most kids cut themselves so often!). Plus, certain organs and bodily functions like metabolism and the workings of the parathyroid gland require calcium to occur with full efficiency.

Further, inadequate calcium intake in childhood can also lead to these children having weaker teeth and more susceptibility to tooth decay later in life, and recent research suggests that insufficient calcium levels can make children more prone to exaggerated weight gain. Calcium helps young people maintain a healthy body weight. 

All of this should be understood with the fact that there is one specific vitamin that is absolutely essential for the absorption of calcium. And it just so happens that that’s Vitamin D.

Vitamin D

Plain and simple, it’s quite possible that even though a child is getting sufficient calcium from dietary and supplement sources that a Vitamin D deficiency will negate the health benefits that come with it. The best way to get Vitamin D for people of any age is actually quite enjoyable – get out and get natural sunlight!

Let’s start by looking at infancy, when a mother will typically be breastfeeding her baby. Vitamin D is very important when a baby is still in infancy because it allows them to not only absorb calcium, but also phosphorous. The need for calcium for bone growth, development and strength is well documented, but babies (and infants in particular) use phosphorous to promote more effective bone mineralization and it is at it this stage of their physical development that the window of opportunity for sufficient mineralization is open for a limited time.

Breast milk only contains limited amount of vitamin D, and of course prolonged sun exposure is inadvisable for children who are still infants. As such, supplementing with a quality Vitamin D supplement may be necessary. This is also a reflection of the fact that newborns will not be able to drink whole cow’s milk until they pass 12 month.

As a guideline, provide your baby with 400IU (international units) of liquid vitamin D every day, with the option of changing the source to a Vitamin-D fortified formula.

The benefits of vitamin D supplementation for kids from toddler to teen are related, as well as there being the fact that Vitamin D boosts their lifelong immunity levels, helps to prevent diabetes and cancer, and ensuring good eyesight.

On last consideration to keep in mind is that children with darker skin will not absorb Vitamin D from sunlight as effectively as more fair skinned children. This is because the pigment and melanin in these children’s skin blocks the sun’s rays more thoroughly. This will apply to African, Latino, South Asian, and Middle Eastern backgrounds. In these instances, bump that 400IU recommendation provided above to 600IU.

Food Sources for Calcium and Vitamin D

Of course, obtaining vitamin D from food sources as well is perfectly natural, and is some ways preferable to supplementing exclusively. The same goes for calcium, so I’ll conclude here by sharing some quality dietary sources for calcium and vitamin D:

Food Sources of Vitamin D: (best sources) - fatty fish (trout, salmon, mackerel etc.), cod liver oil, Portobello mushrooms. (good sources) – tuna, eggs, vitamin-D fortified milk, vitamin-D fortified orange juice, vitamin-d fortified yogurt, cereals, and margarine

Food Sources of Calcium: (best sources)- raw milk, sardines, yogurt and kefir, cheese. (good sources) – kale, broccoli, watercress, bok choy, okra, and almonds.