A well-balanced nutritious diet rich in healthy proteins, fats, vitamins, and minerals is one of the most important things required for a healthy child to grow. Chronic nutrient deficiencies, especially during childhood, can increase the risk of chronic, long-term health issues. 

Nutritional deficiencies can result from consistently eating nutrient-poor foods or from the malabsorption of nutrients. To help combat such nutritional food deficiencies, the United States started food fortification — the practice of adding micronutrients to dietary staples — in the 1920s1. By 2020, 83 countries now require fortification of flour, maize, and rice-related foods. Still, up to 60 percent of children worldwide do not consume fortified foods. 

Examples of food fortification include:

  • Iodization of salt to help prevent goiters (neck masses)
  • Vitamin D added to milk to prevent rickets (weak bones)
  • B vitamins, such as thiamine, added to flour products 

Common nutritional deficiency diseases in children2

  • Iron deficiency – Anemia
  • Vitamin D deficiency – Rickets, poor growth
  • Iodine deficiency – Goiter, mental delay
  • Vitamin C deficiency – Scurvy, bruising 
  • Calcium deficiency – Rickets and weak bones (vitamin D is needed to absorb calcium)
  • Biotin deficiency – Usually associated with a genetic disorder
  • Vitamin A deficiency – Night blindness, susceptibility to infections, growth delay
  • Vitamin B12 deficiency – Anemia
  • Zinc deficiency – Growth retardation, impaired immune system

The following are important nutrients for children.

‌‌‌‌1. Iron

A deficiency in iron is one of the most common nutritional deficiencies in children worldwide, affecting between 30 to 40 percent3. In breastfed infants, iron deficiency is uncommon unless the mother also happens to have an iron deficiency. Children over 12 months of age who drink more than 24 ounces of cow’s milk per day are at increased risk for iron deficiency. This occurs due to milk’s potential to irritate the intestines, resulting in chronic blood loss.

Symptoms of iron deficiency include fatigue, pallor, craving ice, brittle nails, dizziness, and shortness of breath.

Food sources of iron include:

‌‌‌‌2. Vitamin D

Vitamin D deficiency is common in children, affecting up to 60 to70 percent of those tested. It is particularly prevalent during the winter and spring months due to reduced exposure to sunlight. Traditionally, severely low levels of vitamin D are associated with rickets, which results in severe bowing of the legs. Low levels of vitamin D may also increase the risk for bone pain (osteomalacia and growing pains), poor growth, psoriasis, and increased risk for upper respiratory infections. 

Those with darker skin pigment are at higher risk for vitamin D deficiency, even when adequate time is spent in the sun. Melanin, the protein that results in pigmentation, acts as a “natural sunscreen,” which blocks the ultraviolet light (UV-Light) required for the skin to make vitamin D. 

Childhood obesity, which is becoming more common, is also a risk factor for vitamin D deficiency.

Breastmilk is commonly considered a poor source of vitamin D, however, this is only because most lactating mothers are also deficient. Most nursing moms need at least 6,000 IU daily in order to ensure their milk is replete with vitamin D. Pregnant women also frequently supplement with 2,000-5,000 IU per day.

Many pediatricians recommend vitamin D supplementation in babies during the first year of life. The National Academies of Sciences, Engineering, and Medicine states 600 IU (but no more than 1,000 IU) can be given daily. They suggest the safe upper limits for children depends on age. 

  • Children 1 to 3 years of age – 2,500 IU daily maximum
  • Children 4 to 8 years of age – 3,500 IU daily maximum
  • Children 9 and older – limit to 4,000 IU daily maximum 

The Endocrine Society suggests a higher dose limit for kids, recommending an upper limit of 2,000 IU for infants up to 12 months. For those over 1 year of age, they agree with a daily dose of up to 4,000 IU. 

Consult with your physician if you have any questions. Vitamin D is available in liquid drops, gummies formulations, and capsules. 

‌‌‌‌3. Iodine

Iodine is not only important for thyroid health but also for proper development of the reproductive system and brain. Worldwide, this is one of the more common deficiencies primarily due to low iodine content in soils in various places across the globe. A 2004 study4 out of Turkey showed that 46 percent of school-age children were deficient. 

Food sources of iodine

If you are concerned that your child may not be getting sufficient iodine through food, a supplement can be considered. For most kids, the amount of iodine in a multivitamin is sufficient unless a higher dose is recommended by your pediatrician. Suggested dose: As suggested on the label.

‌‌‌‌4. Vitamin C

According to a 2004 study5, 14 percent of males and 10 percent of females were vitamin C deficient. This includes children — 6 percent of kids aged 12 to 17 have low blood levels of vitamin C. Along with bleeding gums, easy bruising, and slow-healing wounds, weakened bones are a serious consequence of this deficiency, with long-term implications for children as they grow. But luckily vitamin C is available in many common foods that many kids enjoy.

Fruit sources of vitamin C

  • Acerola cherries
  • Avocado
  • Guava
  • Papaya
  • Mangos
  • Oranges
  • Pineapple
  • Cantaloupe
  • Kiwi
  • Strawberries

Vegetable sources of vitamin C

  • Bell peppers
  • Bok choy
  • Broccoli
  • Cabbage
  • Kale
  • Brussel sprouts
  • Potato

If consumption of adequate vitamin C through diet is not possible, then supplementing should be considered. Gummie formulations are popular with children, and capsules and powder supplements are also available. Most kids need no more than 250 mg per day although those over 12 can safely take 500 mg per day. 

‌‌‌‌5. Multivitamin

children’s multivitamin is a great way to ensure that at least minimal amounts of various vitamins and minerals are being consumed. A quality multivitamin includes calcium, biotin, vitamin A, vitamin E, zinc, and much more. Pediatric multivitamins come in liquid, gummies, or capsule formulations.

‌‌‌‌6. Melatonin

Trouble sleeping is not unique to adults, and children can also be affected. One study6 showed up to 4 percent (1 in 25) of children have sleep issues. However, medication is not an ideal approach as it is important to avoid prescription medications in children when possible. If your child has sleeping difficulty, evaluating the root cause is absolutely necessary — common causes of poor sleep quality at any age can include serious conditions like anxiety, depression, allergies, or sleep apnea. Once these possibilities have been evaluated and ruled out, 1 to 3 mg of melatonin, a natural hormone that aids the sleep cycle, may be considered. Melatonin should be taken about two hours prior to bedtime. Children formulations include liquids, chewables, and gummies. 

‌‌‌‌7. Omega-3 Fatty Acids

Omega-3 fatty acids are important for the growing brains of young children. However, in many places around the world, children don’t eat the volume of foods rich in essential fatty acids that they should. This can cause delayed growth, skin issues, and neurological issues. 

Omega-3 fatty acids include:

  • Alpha-linolenic acid (ALA, an omega 3 fatty acid), which can be found in flaxseedwalnuts, soy, chia seeds, and hemp seeds.
  • Eicosapentaenoic acid (EPA or icosapentaenoic acid), which is commonly found in fish oilkrill oil, and eggs (if the chickens were fed EPA). 
  • Docosahexaenoic acid (DHA, an omega-3 fatty acid), a large component of the human brain, skin, and eyes. Although important, it is not considered “essential” since it can be manufactured by the body when one has adequate intake alpha-linolenic acid (ALA).

Omega-3 Fatty Acids may have benefits for the following:

  • ADHD – A 2016 study7 demonstrated that omega-3 fatty acids could be beneficial in treating those with ADHD symptoms.
  • Asthma – A 2016 study in Nutrition Research Reviews8 concluded that supplementing with omega-3 fish oil could benefit asthma sufferers, while another 2016 study in Cytokine9 concluded that omega-3 is a promising complementary approach to managing asthma.

Omega-3 fatty acids are available in liquid, chewables, and gummy formulations. 

‌‌‌‌8. Probiotics

When it comes to choosing a children’s probiotic, it’s easy to become overwhelmed. There are so many different types and strains on the market. And though our knowledge of probiotics has grown considerably over the past decade — almost 20,000 scientific reports have been published on the subject in the last 10 years — we are still just beginning to understand the extent of their usefulness and benefits. However, they are believed to be useful in children, and for those with a history of antibiotic use, probiotics should be strongly considered. 

Probiotics are generally considered safe for all ages and anyone with a healthy functioning immune system. If your child is immune-compromised or undergoing cancer treatment, consult with their pediatrician before supplementing. 

In total, it is estimated that most people have between 40 to 50 trillion bacteria in their bodies, mostly in the gut. This is more than the estimated 30 trillion human cells10 present. Seeding of the newborn’s gut starts at birth for most if passage through the birth canal occurs. Also, if breastfed, skin bacteria from the mother helps ensure microbiome diversity. 

Traditionally, probiotics are considered and used for the following:

  • Help soothing digestive issues such as constipation, gas, or acid reflux
  • Help to relieve infantile colic 
  • Irritable bowel syndrome management
  • Crohn’s disease and ulcerative colitis management

The minimal dose of probiotic recommended for children and adults is usually 5 billion CFU (colony-forming units). Teens and adults can take up to 100 billion CFUs once or twice per day. Probiotics come in capsules, chewables, powders, and gummy formulas. Common strains include lactobacillus, bifidobacteria, saccharomyces, or a combination thereof.

Cold and Flu Supplements

When ill, there are also many cough, cold, and influenza supplements available which may help support a stronger immune system while reducing symptoms of illness. A 2012 review study11 recommended vapor rub and buckwheat honey for children. In order to help prevent infections, they recommended probioticszinc sulfate, and nasal saline irrigationVitamin C and elderberry formulations can also be considered. 


  1. Accessed May 25, 2020 http://web1.sph.emory.edu/users/hpacho2/PartnershipsMaize/Bishai_2002.pdf
  2. Accessed May 24h, 2020 http://learnpediatrics.sites.olt.ubc.ca/files/2011/08/GI_-_Nutritional_Deficiencies.pdf
  3. World Health Organization. A guide for programmer managers. Geneva (Switzerland): World Health Organization; 2001. Iron deficiency anaemia assessment, prevention, and control.
  4. Gür E, Ercan O, Can G, et al. Prevalence and risk factors of iodine deficiency among schoolchildren. J Trop Pediatr. 2003;49(3):168‐171. doi:10.1093/tropej/49.3.168
  5. Hampl JS, Taylor CA, Johnston CS. Vitamin C deficiency and depletion in the United States: the Third National Health and Nutrition Examination Survey, 1988 to 1994. Am J Public Health. 2004;94(5):870‐875. doi:10.2105/ajph.94.5.870
  6. Meltzer LJ, Johnson C, Crosette J, Ramos M, Mindell JA. Prevalence of diagnosed sleep disorders in pediatric primary care practices. Pediatrics. 2010;125(6):e1410‐e1418. doi:10.1542/peds.2009-2725
  7. Königs A, Kiliaan AJ. Critical appraisal of omega-3 fatty acids in attention-deficit/hyperactivity disorder treatment. Neuropsychiatr Dis Treat. 2016;12:1869-82. Published 2016 Jul 26. doi:10.2147/NDT.S68652
  8. Nutr Res Rev. 2016 Jun;29(1):1-16. doi: 10.1017/S0954422415000116. Epub 2016 Jan 26.
  9. Farjadian, Moghtaderi, Kalani, Gholami, & Hosseini Teshnizi. (2016). Effects of omega-3 fatty acids on serum levels of T-helper cytokines in children with asthma. Cytokine, 85, 61-66.
  10. http://www.microbiomeinstitute.org/blog/2016/1/20/how-many-bacterial-vs-human-cells-are-in-the-body
  11.  Fashner J, Ericson K, Werner S. Treatment of the common cold in children and adults. Am Fam Physician. 2012;86(2):153‐159.