Four studies about euthyroid patients with Hashimoto’s thyroiditis and three studies about thyroid carcinomas, there were both no significant difference of ghrelin levels compared to the healthy controls (SMD: -0.52, 95% CI [-0.82, 1.85] and SMD: 0.36, 95% CI [-1.03, 1.76]). This evidence concerns the gene GHRL and thyroid gland carcinoma.