What is the primary cause of cretinism?

Cretinism primarily results from a congenital lack of thyroid secretion, also known as congenital hypothyroidism. This condition leads to an underproduction of thyroid hormones, which are essential for normal growth, development, and metabolism in the body. Without adequate levels of these hormones during critical periods of brain development and growth, infants can experience severe physical and intellectual disabilities, characteristic of cretinism.

While other factors like vitamin D deficiency, genetic mutations, and environmental toxins can contribute to various health issues, they do not directly cause cretinism. The key factor in cretinism is the deficiency of thyroid hormone, which is why the answer focuses on the congenital absence of adequate thyroid function.