Vitamin D and Health Outcomes | Then Came the Randomized Clinical Trials

Not long ago, vitamin D was riding high. Beyond its role in calcium homeostasis and bone health, animal studies linked vitamin D deficiency to numerous chronic illnesses including hypertension, diabetes, autoimmunity, and malignancy. Corroborating human observational studies reported associations between vitamin D deficiency and increased risks of hypertension, diabetes, cardiovascular disease, autoimmunity, and cancer. The lay press seized on this chorus of observational studies, testing of serum 25-hydroxyvitamin D levels proliferated, and supplementation with cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) increased substantially.

Then came the randomized clinical trials.

Multiple trials have failed to demonstrate significant benefits of vitamin D supplementation. For example, vitamin D supplementation, compared with placebo, failed to reduce systolic blood pressure in patients with prehypertension and stage hypertension. High-dose monthly oral vitamin D3, compared with placebo, did not reduce risk of incident cardiovascular disease or death. In the Vitamin D and Type 2 Diabetes (D2d) trial, vitamin D supplementation, compared with placebo, failed to lower risk of incident type 2 diabetes in patients with prediabetes.

Prosegui la lettura su “Jama Network“