Vitamin B6 (Pyridoxine HCl) is involved in numerous enzymatic reactions in the body, including those related to the metabolism of amino acids, neurotransmitters, and hormones. Its role in supporting the glandular system—particularly the adrenal, pituitary, and thyroid glands—is primarily based on its involvement in hormone synthesis and regulation. For example, B6 is a coenzyme in the biosynthesis of neurotransmitters such as serotonin and dopamine, which affect hypothalamic-pituitary function and, indirectly, the endocrine system. It is also essential for the synthesis of steroid hormones via modulation of their receptors and metabolism. Deficiency in Vitamin B6 can lead to symptoms such as irritability, depression, and confusion, sometimes attributed to disrupted endocrine and neurotransmitter function. Limited clinical trials and animal studies suggest B6 supplementation can support hormonal balance, especially in conditions like premenstrual syndrome, which involves endocrine function. However, evidence directly linking Vitamin B6 supplementation to broad support of the entire glandular system is moderate rather than robust. Most studies focus on specific glands or hormone-related conditions rather than comprehensive glandular health. Thus, while scientific rationale and some evidence exist, the overall strength of evidence for supporting the whole glandular system is rated as moderate.