The Methionine Hub: Vitamin B12, Tetrahydrofolate, SAM & Homocysteine

This podcast details the physiological importance of **methionine**, an **essential amino acid** that humans must obtain through their diet. It serves as a critical **building block for protein synthesis**, acting as the starting signal for translating genetic code in all living organisms. Beyond its role in structures, it functions as a **precursor to cysteine** and generates **S-adenosylmethionine**, a vital molecule used for transferring methyl groups in biological reactions. The podcast also explains that while methionine can be recycled from **homocysteine**, this process requires **Vitamin B12 and folate** to function correctly. Consequently, a lack of these vitamins can lead to an unhealthy **accumulation of homocysteine**, which is linked to a higher risk of **cardiovascular disease**.