Vitamin A is scientifically validated as essential for the normal functioning of the glandular system, particularly the thyroid and other endocrine glands. Vitamin A exists as retinoids (from animal sources) and carotenoids (from plant sources), and both forms are converted in the body to active retinoic acid, which plays a crucial role in regulating gene expression and cellular differentiation. Research has shown that vitamin A is necessary for the synthesis of glycoproteins, which are essential for hormone production and secretion in various endocrine glands.

Specifically, studies indicate that vitamin A influences thyroid hormone metabolism and can support the maintenance of normal thyroid gland structure and function. Deficiency in vitamin A has been linked to impaired thyroid hormone synthesis and secretion, and supplementation has been shown in some studies to improve thyroid function, particularly in populations where vitamin A deficiency is common (Zimmermann et al., 2002). Additionally, vitamin A impacts the function of the adrenal glands and is involved in the regulation of steroidogenesis.

While vitamin A is not a direct treatment for glandular diseases, its role in supporting the normal physiology of glands is well-documented, and deficiency can lead to glandular dysfunction. Therefore, vitamin A is considered scientifically supported for use in maintaining the health of the glandular (endocrine) system.