A new study published in the Journal of the American Medical Association found that contrary to popular belief, a higher dosage of vitamin D may not actually help to protect children from colds during the winter months.

Dr. Jonathon Maguire, the study’s leader and a pediatrician at St. Michael’s Hospital in Toronto, indicated that the study’s findings “do not support the routine use of high-dose vitamin D supplementation for the prevention of wintertime upper respiratory tract infections among healthy children.”

For years, it has been thought that taking vitamin D can help to prevent or reduce respiratory tract infections in children. For the study, the researchers gave a standard dose of vitamin D drops (400 IU a day) to 350 healthy toddlers. A second group of 350 healthy toddlers received a higher dose of vitamin D (2,000 IU a day). The drops were taken from fall of one year until spring of the following calendar year.

The researchers found that the children with the higher dose of vitamin D have an average of 1.97 colds over the winter months, while the children with the lower dose had an average of 1.91 colds over the winter. According to Dr. Maguire, this difference is not statistically significant.

However, this study did not look at children of other ages, or with different dosing regimens. Additionally, children with underlying health problems were not studied. Vitamin D may still have value in these additional scenarios. Above all, proper hygiene remains the best way to minimize risk of respiratory infections.