Effect of vitamin D supplementation on markers of vascular function: a systematic review and individual participant meta‐analysis Dahkki Beveridge, LA, Khan, F, Struthers, AD, Armitage, J, Barchetta, I, Bressendorff, I, Cavallo, MG, Clarke, R, Dalan, R, Dreyer, G, Gepner, AD, Forouhi, NG, Harris, RA, Hitman, GA, Larsen, T, Khadgawat, R, Marckmann, P, Mose, FH, Pilz, S, Scholze, A, Shargorodsky, M, Sokol, SI, Stricker, H, Zoccali, C, Witham, MD