Vitamin D for Kids: Are They Getting Enough?

Kids can get most of the vitamins they need by eating a healthy, balanced diet. But vitamin D is different. Known as the “sunshine vitamin,” it’s the only vitamin that comes primarily from sunlight, rather than food. 

A healthy dose of sunshine might seem like an easy prescription. Yet low vitamin D status in children is a growing concern worldwide.1,2 In one U.S.-based study, nearly 10% of children were found to be vitamin D deficient, and a startling 60% had insufficient vitamin D levels.3 

Why is this happening, and what does it mean for your child’s health? Here’s what you need to know about vitamin D, and how to make sure your kids are getting enough.

Benefits of Vitamin D for Kids

Vitamin D is essential for growing kids. They need it to build strong, healthy bones, which are developing rapidly as they grow. Vitamin D supports calcium uptake for healthy bone mineralization. Without it, bones can become soft and brittle, teeth are more prone to cavities, and growth may be stunted. Serious vitamin D deficiency in children can lead to rickets, a disease characterized by weak, misshapen bones.

But even a milder vitamin D deficiency can have a negative impact on long-term bone health. Childhood is a crucial period for building up bone density, as bones are still increasing their mass. Later in adulthood, bones begin losing mass. The more bone density your kids build now, the more they will have later as older adults.

Vitamin D has long been recognized for its bone health benefits, but it may have other important benefits as well. Recent research suggests it may be particularly important for immune health. Vitamin D deficiency has been linked with a higher risk of respiratory issues, allergies, and autoimmune responses in both children and adults.4,5 It has been suggested that the lack of sunshine in the winter, and resulting lack of vitamin D, may help explain the seasonality of common respiratory infections.6

Limited sun in the winter is one of the most common reasons for a drop in vitamin D levels, but there are several other factors that can make it harder for kids to get enough vitamin D. Here are a few of the top reasons why your kids may be low in vitamin D.

7 Reasons for Low Vitamin D in Children

1. Indoor Lifestyles

We live in an age when kids are less likely to spend their time playing and exploring outdoors, and more likely to spend their time indoors playing with digital devices and video games. This is especially true in cities that lack safe outdoor spaces for kids to socialize. As a result, kids aren’t getting the kind of regular sun exposure that previous generations got. This not only reduces their opportunity to make vitamin D, it also affects their circadian rhythms, which can make it harder for them to sleep.

2. Increased Sunscreen Use

Once upon a time, parents were advised to give their babies regular sun baths to increase their vitamin D. These days, we are much more cautious about UV exposure, thanks to increased awareness of the risks of skin cancer. Parents conscientiously slather their kids with sunscreen before letting them play outside. The downside to this is that those same UV rays that sunscreen blocks are also what the skin uses to make vitamin D. So the skin’s ability to make vitamin D is further reduced.

3. Winter

It’s harder for all of us to make enough vitamin D in the winter. The days are shorter and the sun’s rays are weaker and farther away. Bad weather can hide the sun and keep kids indoors for much of the time. When they do go outside, they bundle up against the cold, which also blocks the sun from hitting their skin. Though our bodies store up vitamin D in the summer, those reserves start dwindling as the colder months wear on.

4. Geographic Location

The further you live from the equator, the less UV light is going to reach you in the colder seasons. In the northern U.S. and Canada, for example, the sun is too low in the sky to allow for practically any vitamin D production during the winter, which can last 4-5 months out of the year.7 If you happen to live in an area with a lot of air pollution, that can also reduce vitamin D production, regardless of the season.8

5. Darker Skin

Melanin, the pigment that makes skin tones darker, acts as a natural sunscreen, helping to block the sun’s UV rays. This means that children with darker skin tones need more sun exposure in order to make enough vitamin D. This helps explain why the rates of vitamin D deficiency and insufficiency are significantly higher for brown and black children.3

6. Vegan and Non-Dairy Diets

Vitamin D is only found in a handful of foods, and only in small amounts. It’s found naturally in fatty fish like salmon and tuna, wild mushrooms, and egg yolks, and often added to milk products. None of us would get enough vitamin D if we relied on food sources alone, but kids who regularly eat these foods do have an advantage over those who don’t. And since most of these foods are meat and dairy, that means vegans and those who are dairy-sensitive will have a harder time meeting their vitamin D targets. 

7. Maternal Vitamin D Levels

Babies get their initial store of vitamin D from their mothers in the womb and during breastfeeding. If mom’s vitamin D levels are low, the child is at greater risk of low vitamin D.9 Recent evidence suggests that low vitamin D levels during pregnancy is a common problem.10 Taking supplemental vitamin D during pregnancy and breastfeeding can help give your child a healthier start. The American Academy of Pediatrics also recommends giving breastfed infants supplemental vitamin D, since the amount that’s carried in breastmilk is likely not enough.

Vitamin D Supplements for Kids

Considering how easy it is for kids to be low in vitamin D, especially when any of the factors  above apply, vitamin D supplements for children make a lot of sense. Both the AAP and the Institute of Medicine recommend that all children age 1 and up receive at least 600 IU of vitamin D per day from food or supplements to avoid deficiency. It would take a lot of milk and fish to meet this daily target without any help from vitamin D supplements.

This is also a minimum recommendation. The safe upper limit for daily vitamin D intake, according to the IOM, is 2500 IU for children ages 1-3, 3000 IU for kids 4-8, and 4000 IU for kids 9 and up.11 Since the amount of vitamin D in foods ranges from the low hundreds (about 100-150 IU for a glass of milk) up to about 1000 IU for a full serving of wild salmon, it should be easy to stay within the healthy range, even when combining vitamin D supplements with food sources.

Here are a few things to look for when choosing a vitamin D supplement for kids:

1. The Form of Vitamin D

There are two kinds of vitamin D that you may find in supplements: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is the kind that our own skin produces, while vitamin D2 is the kind that fungi (mushrooms and yeast) produce. Although our bodies can use either type, we use vitamin D3 much more efficiently. Research shows that vitamin D3 is better at raising blood vitamin D levels12 and also seems to last longer in the body,13 making it more effective than vitamin D2.

2. The Source of Vitamin D

Historically, most vitamin D3 supplements were sourced from lanolin, a waxy secretion from sheep’s skin removed from the wool. However, there are now vegan vitamin D3 supplements sourced from lichen, a mossy growth found on rocks and trees, which is a combination of fungi and algae. This is great news for those who prefer their supplements from a vegan-friendly, non-animal source.

3. The Form of Supplement

Capsules, chewables, or drops? Most kids will prefer something they can chew over something they have to swallow. Liquid supplements are an option, but it can be harder to control the dose when you are squeezing out drops. Gummy vitamins are always popular – it’s easy to get kids to take their vitamins when they taste like a treat. Just check the label to make sure there aren’t any artificial sweeteners or flavors. And keep them out of reach, so the kids don’t start eating them like candy.

Our Vegan Vitamin D3 Gummies for Kids are sourced from lichen and deliver 1000 IU vitamin D in just one gummy per day. They come in a delicious strawberry flavor and are non-GMO and gluten free, with no corn syrup, artificial sweeteners, artificial flavors, or preservatives.

References:

1.  Shin, Youn Ho et al. “Vitamin D status and childhood health.” Korean journal of pediatrics vol. 56,10 (2013): 417-23. doi:10.3345/kjp.2013.56.10.417

2. Suskind DL. Nutritional deficiencies during normal growth. Pediatr Clin North Am. 2009 Oct;56(5):1035-53. doi: 10.1016/j.pcl.2009.07.004. PMID: 19931062.

3. Kumar, Juhi et al. “Prevalence and associations of 25-hydroxyvitamin D deficiency in US children: NHANES 2001-2004.” Pediatrics vol. 124,3 (2009): e362-70. doi:10.1542/peds.2009-0051

4. Aranow, Cynthia. “Vitamin D and the immune system.” Journal of investigative medicine : the official publication of the American Federation for Clinical Research vol. 59,6 (2011): 881-6. doi:10.2310/JIM.0b013e31821b8755

5. Mailhot, Geneviève, and John H White. “Vitamin D and Immunity in Infants and Children.” Nutrients vol. 12,5 1233. 27 Apr. 2020, doi:10.3390/nu12051233

6. Cannell JJ, Vieth R, Umhau JC, Holick MF, Grant WB, Madronich S, Garland CF, Giovannucci E. Epidemic influenza and vitamin D. Epidemiology & Infection. 2006 Dec;134(6):1129-40.

7. “Vitamin D”. The Nutrition Source, Harvard School of Public Health.

8. “6 Things You Should Know about Vitamin D.” Harvard Health Publishing, Oct. 2020.

9. Dawodu, A, and C L Wagner. “Prevention of vitamin D deficiency in mothers and infants worldwide - a paradigm shift.” Paediatrics and international child health vol. 32,1 (2012): 3-13. doi:10.1179/1465328111Y.0000000024

10. Bodnar LM, Simhan HN, Powers RW, Frank MP, Cooperstein E, Roberts JM. High prevalence of vitamin D insufficiency in black and white pregnant women residing in the northern United States and their neonates. J Nutr 2007;137:447–52.

11.  “Vitamin D: Fact Sheet for Health Professionals.” National Institutes of Health, Office of Dietary Supplements.

12.  Tripkovic, Laura et al. “Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis.” The American journal of clinical nutrition vol. 95,6 (2012): 1357-64. doi:10.3945/ajcn.111.031070

13. Jones KS, Assar S, Harnpanich D, Bouillon R, Lambrechts D, Prentice A, Schoenmakers I. 25(OH)D2 half-life is shorter than 25(OH)D3 half-life and is influenced by DBP concentration and genotype. J Clin Endocrinol Metab. 2014 Sep;99(9):3373-81. doi: 10.1210/jc.2014-1714. Epub 2014 Jun 2. PMID: 24885631; PMCID: PMC4207933.