Vitamin D for type 2 diabetes prevention: cost-effective, but not yet cost-saving

Briody and colleagues provide the first cost-effectiveness analysis of vitamin D for preventing type 2 diabetes in US adults with prediabetes, addressing a gap identified by the 2024 Endocrine Society guideline.1 The microsimulation is careful and transparent, and the conclusion that supplementation is economically attractive is plausible. The headline that vitamin D is “cost-saving,” however, rests on features of the model's own uncertainty that deserve a closer look.