Which one among the following vitamins is necessary for blood clotting ?

Vitamin K is essential for the process of blood coagulation, often referred to as the "clotting vitamin" [2]. It acts as a vital co-factor for the synthesis of several coagulation proteins in the liver, specifically clotting factors II (prothrombin), VII, IX, and X [2]. This biochemical process involves the gamma-carboxylation of glutamate residues, which allows these factors to bind calcium ions and perpetuate the clotting cascade [1]. Without sufficient vitamin K, the body cannot produce functional clotting factors, leading to impaired coagulation and increased risks of bruising or excessive bleeding [2]. While other vitamins have distinct roles—such as Vitamin A for vision and growth, Vitamin D for calcium absorption and bone health, and Vitamin C for collagen synthesis—only Vitamin K is directly necessary for the blood clotting mechanism.

Sources

1. [2] https://medlineplus.gov/ency/article/002407.htm
2. [1] https://www.ncbi.nlm.nih.gov/books/NBK551578/