Korzonek-Szlacheta I, et al. - Researchers looked into the link between mean platelet volume (MPV) and serum 25-hydroxyvitamin D (25[OH]D) concentration in patients with stable coronary artery disease. Study cases were divided into 3 groups: group 1—25(OH)D<10 ng/mL, group 2—25(OH)D 10–20 ng/mL, and group 3—25(OH)D>20 ng/mL, with similar demographics across all groups. A negative correlation was noted between MPV and 25(OH)D. Vitamin D was found to be associated with thrombosis and hemostasis, even though interplay of multiple factors was suggested to underlie the impact of vitamin D on platelet size and function. Platelets are another possible element through which vitamin D deficiency could exert adverse cardiovascular outcomes.