THE ARTICLE "Is there any way to tell whether you are getting enough vitamin D?" (Health/Science, Feb. 4) cites recommendations for blood testing and possible supplementation with vitamin D for "everyone." However, a study in Science Daily raises a contrary concern about vitamin D supplementation. According to this report, the assumption has been that vitamin D supplements may protect against disease. However, this new research demonstrates that ingested vitamin D is immunosuppressive, and that low blood levels of vitamin D may be a result of the disease process in some individuals. Supplementation may make the disease worse for them. So, scientific conclusions are not necessarily simple, and what to do may take more figuring out.
Dr. MICHAEL I. GOOD
Chestnut Hill
The writer is in the psychiatry department at Harvard Medical School.
