NANP Board Practice Exam 2025 - Free NANP Board Practice Questions and Study Guide

The synthesis of protein throughout the body is critically dependent on a variety of vitamins, and in this context, vitamin B6 plays a crucial role. It serves as a coenzyme in numerous enzymatic reactions involved in amino acid metabolism, which is essential for protein synthesis. Vitamin B6 assists in the conversion of amino acids to neurotransmitters and other vital compounds, thus impacting overall protein metabolism.

Vitamin A primarily functions in vision, immune function, and cellular communication, but it does not have a direct role in protein synthesis. Vitamin C is mainly known for its role in collagen synthesis, antioxidant protection, and the enhancement of iron absorption rather than directly impacting protein synthesis across the body. Vitamin D is primarily related to calcium homeostasis and bone health, and while it plays roles in some cellular processes, it does not have a direct function in the synthesis of proteins.

Therefore, the emphasis on vitamin B6 in relation to protein metabolism is accurate, as its deficiency leads to impaired protein synthesis and amino acid metabolism, subsequently affecting various bodily functions dependent on proper protein levels.