By Dr. Nicole Avena

While childhood micronutrient deficiencies are far more commonly seen in the developing world, it is still crucial to be aware of your child’s nutritional intake and make sure they are getting adequate amounts of all important nutrients. Rounding out your child’s diet with the necessary micronutrients will ensure their optimal health and development. Four of the most impactful micronutrients for childhood development include vitamin A, zinc, iron, and iodine. In this article you will find information about the functions of these micronutrients in the body, how to tell if your child has a deficiency, and ways to supplement your child’s diet with these critical nutrients.

Vitamin A

This micronutrient is crucial in building a strong immune system in young children. Vitamin A deficiency increases susceptibility to infection. It is specifically correlated with less than optimal antibody and cell-mediated forms of immunity. More serious cases of vitamin A deficiency can result in xerophthalmia – a disease of the eye that causes severe dryness and inflammation. This impairment of the eyes due to lack of vitamin A can also lead to forms of blindness in children. While vitamin A deficiencies are rare in developed countries, extremely selective eating patterns in children can lead to deficiencies in any part of the world. Some symptoms associated with vitamin A deficiency are light sensitivity as well as higher susceptibility to infection. The easiest way to prevent and even heal these symptoms is making sure your child eats a wholesome and varied diet.

Dietary sources of vitamin A include:

  • Sweet Potato
  • Spinach
  • Pumpkin
  • Carrots

An oral supplement for vitamin A can also be taken for more concentrated dosage.


Zinc is a type of trace metal, and it has been shown to be important in cognitive development in children. Zinc is found for the most part in the brain. This micronutrient is known for its role in propagating DNA and RNA so that cells can grow healthily. Because of its key role in cell replication and division, zinc deficiencies often impair normal growth in children. Zinc deficiency is more common in developed countries than vitamin A, especially for children that do not eat meat or follow a plant-based diet. Some signs of possible zinc deficiency in children include lethargy, weight loss, and decreased ability to acquire new skills. 

Dietary sources of zinc include:

  • Oysters, lobster, and other seafoods
  • Pork and beef
  • Fortified breakfast cereals

Zinc supplementation may be a viable option for children who are picky eaters or do not eat meat.


One of the most significant effects of an iron deficiency is anemia. This condition affects levels of hemoglobin in the blood, decreasing oxygen transport, a crucial function for overall health. Iron, like zinc, is found in abundance in the brain and is involved with cognitive functions, as well. Iron and zinc often come from similar dietary sources like red meat, so deficiencies in both micronutrients can occur simultaneously. Sufficient iron levels in the body also depend on its ability to absorb iron. Foods rich in vitamin C aid iron absorption while foods with phytates – like soy – can inhibit absorption. Fatigue and shortness of breath are common signs that indicate iron deficiency.

Dietary sources of iron include:

  • Red meat
  • Legumes
  • Fortified cereal

Iron deficiency is a very common problem in all parts of the world. Taking iron as an oral supplement is also a viable solution to this problem.


This mineral is essential for the proper functioning of the thyroid gland. The thyroid releases a hormone that affects many other organs in the body. Iodine is needed to synthesize thyroid hormone. With insufficient levels of this hormone – the cause of hypothyroidism – development is impaired, especially in infancy and childhood. Normal puberty, specifically, can be negatively affected by improper functioning of the thyroid due to lack of iodine. One of the most prominent signs that a child may be iodine deficient is presence of a goiter on the neck.

Dietary sources of iodine include:

  • Iodized salt
  • Fish
  • Some fortified breads and cereals

Nicole Avena, PhD, is Assistant Professor of Neuroscience at Mount Sinai School of Medicine and Visiting Professor of Health Psychology at Princeton University. She is the author of several books, including What to Feed Your Baby and Toddler, and What to Eat When You’re Pregnant.  The post was adapted from What to Feed Your Baby and Toddler.