The ABCs of common nutritional deficiencies in kids

To ensure optimal development and prevent disease, your child’s body needs various minerals and vitamins. These minerals and vitamins, referred to as micronutrients, are not naturally produced by the body, which means they need to be consumed by food. A nutritional deficiency occurs when your child’s body does not absorb or get the necessary nutrients from their diet. Nutritional deficiencies, including rickets, iron deficiency anaemia, obesity, coronary heart disease, type 2 diabetes, cancer, and osteoporosis, can lead to various health problems in children. “The best way to prevent a nutritional deficiency is to include a variety of whole and minimally processed foods in your child’s diet,” says registered dietician Abigail Courtenay. She adds that a readily consumed and tasty nutritional milk supplement can also be used to act as nutritional “insurance” when your child’s food intake is not as good as it should be (especially when she is sick or during times of rapid growth).

We unpack four of the most common nutritional deficiencies in children and provide advice on what you can do to ensure that your child gets enough of these nutrients in her diet.  

C is for Calcium

This is one of the most common nutritional deficiencies seen in young children. “Calcium is important for bone mineralisation and maintenance of growing bones in children,” explains Abigail. “Toddlers need 700mg calcium per day, and older children need between 1 000 and 1 300mg per day, depending on their age,” says Abigail. Each person absorbs calcium at different rates, and dietary factors such as protein and phosphorus intake or their vitamin D status can also affect calcium absorption. “The rise in the risk of calcium deficiencies may be due to dietary restrictions of dairy, or the introduction of unfortified non-dairy milks,” explains Abigail. If your little one can’t consume normal dairy products, ensure the non-dairy alternative you choose is calcium-fortified.

D is for Vitamin D

Vitamin D is essential for calcium absorption, so make sure your child gets enough as it can affect bone mineralisation, tooth health, and even muscle contraction and joint health. It also plays a role in preventing chronic diseases like cancer, heart disease, and diabetes. “The main risk of a vitamin D deficiency is hypocalcaemia rickets (rickets due to low calcium levels),” explains Abigail. She cautions that an excessive intake of vitamin D may cause nausea, vomiting, loss of appetite, abdominal pain, muscle weakness, muscle and joint aches, confusion, fatigue, or damage to the kidneys. “Supplementation should always be discussed with your healthcare provider.”

Signs of a vitamin D deficiency may include:

• A softening or thinning of the scalp or the fontanel may open or bulge
• Painful and swollen joints.

Good to know: These signs and symptoms are not unique to vitamin D deficiency and could also be due to other problems. Eventual long-term symptoms include a “bow” leg appearance of rickets or the ribs’ beading (where bead-like cartilage masses form on the ribs).

Daily vitamin D requirements for children

Vitamin D is formed when you expose your skin to sunlight. The amount you need from food or supplements depends on your geographical location, skin tone, and time spent outside. Those with darker skin may not be getting as much vitamin D from sunlight as their melanin (the dark pigmentation) absorbs the sunlight instead of converting it to vitamin D. The daily reference intake for infants is 400IU per day and 600IU per day for “at risk” children (those with dark skin or those covered for religious reasons). Optimal blood levels are not currently known.

I is for Iron

Iron is a nutrient found in trace amounts in every cell in the body. It forms part of your red blood cells as well as your muscle cells. The purpose of these molecules is to carry oxygen. Children between the ages of one and three years are at the highest risk of iron deficiency anaemia due to their rapid growth. Iron deficiency inhibits the amount of oxygen each cell receives, including that of the brain, negatively irreversibly influencing brain development.

Signs of an iron deficiency

• Fatigue
• Pale skin, inner lips, and conjunctiva (the skin in your eyes)
• Spoon-shaped nails (koilonychia) that are dull and lackluster or may have poor perfusion (when pressed, they remain white for a prolonged period before turning pink again)
• The tongue may be pale or, in extreme cases, turn magenta and become inflamed, or it may become smooth and slick.

Daily iron requirements for children

Toddlers need approximately 7mg of iron a day, and older children need 8 to 15mg a day, depending on their age. Iron deficiency can be corrected through diet and supplementation. While non-heme iron (usually from plants) is not as well absorbed, this can be enhanced by pairing it with vitamin C or heme foods (usually from animal products).

Best heme iron sources:

• Oysters
• Liver
• Red meat, like beef
• Dark meat of poultry
• Tuna

Best non-heme iron sources:

• Tofu
• Lentils
• Beans
• Peas

Good to know: If you suspect your child has an iron deficiency, speak to your healthcare provider. Children can develop iron toxicity if they mistake iron supplements for sweets and eat them excessively. Symptoms of an iron overdose include fatigue, loss of appetite dizziness, nausea, vomiting, headache, weight loss, and shortness of breath.  

Z is for Zinc

Zinc stimulates the activity of about 100 enzymes. It supports immunity, is needed in wound healing, maintains your sense of smell and taste, helps with DNA synthesis, and supports normal growth and development.

Zinc deficiency can result in:

• Growth failure
• Poor appetite
• Decrease or distorted sense of smell and taste and poor wound healing.

Physical signs to look out for may also include dermatitis and thin or sparse hair with a lackluster appearance.

Good to know: It is difficult to diagnose a zinc deficiency as laboratory parameters are of limited value. If you suspect a zinc deficiency, seek medical assistance from your healthcare provider, who can conduct a comprehensive medical, physical, and lifestyle assessment to help determine the cause of the symptoms your child is experiencing.

The daily zinc requirement for toddlers is 3mg per day and 5 to 11mg per day for older children, depending on their age.

Include these foods in your child’s diet: Zinc is best absorbed from animal sources, with Atlantic oysters containing the most zinc per serving. If you can’t get your kids to eat oysters, red meat and poultry are also great zinc sources.

Other good food sources include:

• Beans
• Nuts
• Certain seafood
• Wholegrains
• Dairy products.

Good to know: Vegetarians may become zinc deficient if they’re not monitored carefully as the phytates from whole grains, cereals and legumes may decrease zinc absorption.