Severe vitamin D deficiency in children can lead to rickets — a disease of the bones’ growth plates that can slow growth and deform bones.

Published: August 18, 2021

A severe vitamin D deficiency in children can lead to rickets — a disease of the bones’ growth plates that can slow growth and deform bones.

Sunlight is the primary source of vitamin D. Another source is vitamin D fortified milk. Some foods also have a small amount of naturally occurring vitamin D.

“The overall incidence of rickets is thought to be increasing worldwide — even in developed nations,” said Prasanthi P. Gandham, M.D., a pediatric endocrinologist with Norton Children’s Endocrinology, affiliated with the UofL School of Medicine. “We’re not 100 percent sure why that is.”

“Screening for bone disease is an important part of a child’s overall care,” said Dr. Gandham, who treats patients at the Norton Children’s metabolic bone clinic.

Rickets can give a child bowed legs and a pot-bellied appearance. Children with rickets often have a softening of their skull and delayed closure of their fontanels, the spaces between the bones of the skull.

Muscle weakness and a decrease in muscle tone are common with rickets, which can cause delayed achievement of motor milestones.

Rickets also can be painful. Younger children unable to express what they’re feeling might be irritable and difficult to console.

Vitamin D deficiency risks

Vitamin D deficiency in children is a risk with premature babies because the fetus receives vitamin D from the mother, particularly in the third trimester.

Vegetarians and vegans are at a slightly higher risk. Very few foods naturally contain a high amount of vitamin D, but the foods that do contain vitamin D tend to be either fish or meat-based. For vegetarians who consume dairy products, drinking fortified milk can help.

Individuals with dark skin tones often will need longer exposure or more exposure to sunlight and ultraviolet (UV) radiation to get adequate vitamin D production. In general, anybody who has inadequate sun exposure is at high risk.

Obesity is also a risk factor, because vitamin D tends to get trapped in fatty tissue.

Making up for vitamin D deficiency

Treatment of nutritional rickets involves vitamin D replacement. Doses are typically daily over several months and depend on a child’s age.

If giving a child a daily dose for an extended time is difficult, a very high single dose — Stoss therapy — may be an option for children at least 3 months old.

Once vitamin D therapy is complete, children transition to maintenance dosing of vitamin D.

Rickets typically goes away within three months of addressing vitamin D deficiency, though skeletal healing takes longer. Lab results can determine whether the body’s chemistry is back to normal, and X-rays can confirm skeletal healing.

In the early stages of treatment for rickets, calcium replacement also is needed. This prevents a condition called hungry bone syndrome, where bones take up too much of the body’s available calcium.