"Problem of pain": Further questions for the utility of vitamin D for chronic pain after gastrointestinal surgery.

This letter to the editor provides a short review on the number of different disease states that have been linked with at least a factorial relation with deficiency in vitamin D (defined at less than 50 nmol/L or 20 ng/mL serum levels) and tries to raise some question in regards to the recent publication within the journal. This letter also highlights some of the recent work within the neurology literature which demonstrates that supratherapeutic levels of vitamin D might provide benefit for patients suffering with different disease states, with the D-Lay MS randomized clinical trial utilizing 100000 international units every 2 weeks and some of the migraine literature supporting a higher target between 50 ng/mL to 100 ng/mL which might provide benefit for patients suffering from migraines. The letter concludes with a key question for further research asking about whether in gastrointestinal surgery should a normal vitamin D level, defined as 50 nmol/L (20 ng/mL) or greater, be targeted or if there might be a role for supratherapeutic dosing within gastrointestinal surgery.