Taking vitamin D and fish oil during pregnancy may reduce risk of croup, experts flag

05 Sep 2022 --- The number of viral croup infections, often revealing itself in the “barking” cough of the infants and children who may contract it, may be reduced by the consumption of fish oil and vitamin D by pregnant mothers, according to a clinical study.

The study was presented at the European Respiratory Society International Congress in Barcelona, Spain. It is based on a randomized control trial and is reported to be the first large clinical trial of the effects of the nutrients on croup.

“There is currently no vaccine against the pathogen that causes this disease,” says Dr. Nicklas Brustad, a researcher at the Copenhagen prospective studies on asthma in childhood (COPSAC) at Copenhagen University Hospital in Denmark.

“Therefore, other preventive strategies are needed, and measures initiated during pregnancy might be important since croup occurs in babies and young children. For such purposes, there is evidence that both vitamin D and fish oil could have an influence on the immune system.”

Consuming a high dose of vitamin D and fish oil while pregnant reduced the risks of croup by up to 40%.New cure for an old problem
The study included 736 pregnant mothers who had received care from COPSAC over the past 12 years. They were divided into four groups and given different amounts of fish oil with omega 3 fatty acids and vitamin D from the time they were 24 weeks pregnant until birth. 

The first group received 2800 IUs of vitamin D a day along with 2.4 g of fish oil, the second group was given olive oil and 2800 IUs of fish oil a day, the third group was given 2.4 g of fish oil and 400 IUs of vitamin D a day and the last group was given 400 IUs of vitamin D and olive oil everyday day.

The research team found that, compared to pregnant mothers who took olive oil during pregnancy, children of mothers who consumed fish oil had an 11% chance of developing croup, or 38% less risk. Moreover, they found that when pregnant mothers took a higher dosage of vitamin D their children also had an 11% chance of developing croup, 40% less than children whose mothers took the normal dose. 

“Our findings suggest that vitamin D and fish oil could be beneficial against childhood croup in sufficiently high doses,” remarks Brustad. “These are relatively cheap supplements meaning that this could be a very cost-effective approach to improving young children’s health.”

Continued benefits
The researchers continued to monitor the children until they were three years of age. Children with suspected cases of croup were sent to their doctor for diagnosis. In total, there were 97 confirmed diagnoses among the entire group of children. 

The researchers confirmed that, previously, COPSAC had already studied other benefits of fish oil and vitamin D, including effects on the central nervous system, body weight and composition, improved bone development and asthma. They stated that they will continue to monitor the children and plan to study why some are more predisposed to infections. 

“We are not sure of the exact mechanisms behind the beneficial effects of vitamin D and fish oil, but it could be that they can stimulate the immune system to help babies and young children clear infections more effectively,” concludes Brustad.

Edited by William Bradford Nichols