This means, a clear tendency to show low calcidiol levels and increased PTH levels in severe obesity in relation to other nutritional situations is detected; in this way, other authors have highlighted that this condition might constitute a metabolic and/or cardiovascular risk factor.2, 4, 5, 6, 10, 13, 14, 16, 26, 27. Here, PTH is linked to obesity due to melanocortin 4 receptor deficiency.