Can Vitamin D Protect Kids From Long COVID?

COVID-19 has affected children around the world. While most kids recover quickly, some continue to have health problems long after the infection is gone. A new study looked at whether vitamin D might play a role in preventing these long-term symptoms.

What is Long COVID?

Long COVID means having symptoms that last for months after the initial COVID-19 infection. According to the World Health Organization, it is when symptoms continue for at least 2 months and usually start within 3 months of the infection.

In children, long COVID can look different from one child to another. Some may feel tired all the time, have trouble concentrating, or struggle with headaches and sleep problems. Others may have stomach issues, heart palpitations, or muscle aches.

While COVID-19 is usually milder in kids than adults, children can still develop long COVID. In this study, more than 40% of hospitalized children experienced long-term symptoms, showing that kids are not immune to this condition.

What Did the Research Discover?

Vitamin D is known for helping keep bones strong, but it also plays an important role in the immune system. It helps the body fight infections and regulate inflammation.

The researchers wanted to know if vitamin D levels in children made a difference in who developed long COVID. They found that kids with low vitamin D levels were more than twice as likely to develop long COVID compared to those with healthy levels.  According to the recommendations of the European Vitamin D Association (EVIDAS), a concentration of 25(OH)D between 30 and 100 ng/ml was considered optimal; 20–30 ng/ml was classified as vitamin D insufficiency; and concentrations below 20 ng/ml (<50 nmol/L) indicated vitamin D deficiency.

• Study design: This was a prospective cohort study—researchers followed children over time to see how their health changed.
  
• Who was studied: 162 children between 1 month and 18 years old were hospitalized with confirmed COVID-19 between September 2022 and March 2024. Their vitamin D levels were measured when they entered the hospital.
  
• Follow-up: After leaving the hospital, 134 children agreed to follow-up visits for up to a year. Parents and older kids answered questionnaires about long-term symptoms.
  
• Results:
  
  • 56 children (41.8%) developed long COVID, while 78 recovered fully.
    
  • Children with low vitamin D levels had longer hospital stays and higher risks of developing long COVID (2.2 times higher risk).
    
  • Neurological symptoms were almost twice as common in kids with low vitamin D.
    
  • Musculoskeletal symptoms were also more frequent in kids with vitamin D deficiency.
    

Low vitamin D seemed especially linked to neurological problems (like headaches, memory issues, or poor concentration) and muscle and joint pain. This suggests that vitamin D might help protect the brain and muscles from long-lasting effects of COVID-19.

The authors caution that this was research, not a treatment recommendation. More studies are needed before doctors can say exactly how vitamin D should be used to prevent long COVID in children. These findings suggest a link between vitamin D levels and the risk of long COVID, though the study could not prove cause and effect.

How Can I Apply This Information?

This study highlights the importance of vitamin D for children’s overall health and recovery after COVID-19. While we don’t yet know the perfect dose of vitamin D to prevent long COVID, parents and doctors can take steps now:

• Check vitamin D levels: Ask your child’s doctor whether they may need testing, especially if they don’t get much sunlight or have health conditions.
  
• Encourage healthy habits: Balanced nutrition, time outdoors in sunlight, and regular physical activity all support healthy vitamin D levels.
  
• Follow medical advice: If a child has low vitamin D, doctors may recommend supplements. Don’t start high doses without professional guidance.
  
• Stay informed: Remember, this was one research study. More studies are needed to confirm how vitamin D affects long COVID.
  

The bottom line: Vitamin D may play a protective role against long COVID in kids, especially when it comes to brain and muscle symptoms. Supporting healthy vitamin D levels is one more way to help children recover well after COVID-19.

Source:

Perestiuk V, Kosovska T, Dyvoniak O, Volianska L, Boyarchuk O. Vitamin D status in children with COVID-19: does it affect the development of long COVID and its symptoms? Frontiers in Pediatrics. 2025 Feb 14;13. https://pmc.ncbi.nlm.nih.gov/articles/PMC11881026/