Leila Cruikshank

What happens if I don't get enough vitamin D?

Vitamin D deficiency is common not only in cystic fibrosis but also in the general population. Given the fact that individuals with CF have fat malabsorption, they are at higher risk for vitamin D deficiency (vitamin D dissolves in fat). Furthermore, many individuals with CF have low bone mineral density or “thin bones” so normalizing blood levels of vitamin D may be even more important in CF to optimize bone health. The normal range for blood vitamin D levels varies but most literature suggests that the optimal level is around 75-100 nmol/L in the bloodstream. Using this cut-off, the vast majority of individuals with CF are considered vitamin D deficient. As part of your yearly bloodwork, we measure your vitamin D level in your blood. Preliminary research in our clinic show that 85% of the adult CF population followed at St. Michael’s Hospital has blood levels below 75 nmol/L.