“…Chatterjee Montgomery et al analyzed the association of serum 25‐OH vitamin D (25OHD) level with development of diabetes among 2362 participants in a trial of persons with high‐risk prediabetes and overweight/obesity randomized to vitamin D3 4000 IU daily versus placebo; intratrial mean serum 25OHD ≥ 40 ng/ml was associated with significant ~50% reduced risk of T2D both in Black and in White participants, although only among those with BMI < 40 kg/m 2 . 23 Kim et al examined serum 25OHD and its metabolites among 114 children with islet autoimmunity and 116 controls, finding that 24,25 (OH) 2D3, an inactive catabolite, was associated with greater likelihood of islet autoimmunity and that 3‐epi‐25 (OH) D3 was protective against progression to T1D among children who seroconverted at an older age, but that neither 25OHD nor 1,25 (OH) 2D3 was associated with islet autoimmunity or with T1D development. 24 …”