Vitamin D deficiency worsens PCOS symptoms

This study found that women with PCOS had significantly lower vitamin D levels than healthy women, and genetic analysis suggested low vitamin D may increase PCOS risk. However, Figure 1 shows the proportion of women with low vitamin D was nearly identical between groups, and the study does not show vitamin D directly worsens specific symptoms like high testosterone or irregular periods.

• The PCOS group was heavier on average, but authors adjusted for BMI in their models
• 14 measurements were compared without correcting for the number of tests, so some results may be false positives
• The study supports vitamin D as one factor among several in PCOS, but not that it worsens symptoms
• All participants were from a single hospital in China, limiting broader applicability