HIV-positive people beginning antiretroviral (ARV) treatment may experience stunted immune recovery if they are deficient in vitamin D. Publishing their findings in Clinical Nutrition, researchers conducted a prospective study of 398 HIV-positive people starting treatment or who had been on ARVs for no longer than six months upon entering the study.

The researchers measured participants’ vitamin D levels upon their enrollment in the study and classified those levels as deficient, insufficient or sufficient. (Deficient vitamin D is lower than insufficient.) They also measured participants’ CD4 counts at enrollment and after three, six, 12 and 18 months.

A respective 17 percent, 60 percent and 23 percent of participants had deficient, insufficient and sufficient vitamin D levels at the study’s outset.

All the participants with low vitamin D saw smaller gains in CD4 cells during the study than those with sufficient levels of the vitamin. The biggest difference in CD4 gain was between those with deficient and sufficient levels: a deficit of 26 to 65 cells. This deficit was the most pronounced among those who were 35 or younger and among those with a baseline body mass index of less than 25.  

The researchers concluded that vitamin D supplementation may improve CD4 cell recovery among those starting ARVs. However, future research is needed.

To read a press release about the study, click here.

To read the study abstract, click here.