Vitamins

Question 1

Vitamin A what is the active and storage form

Answer 1

**Retinol is the ** storage form and Retonic Acid is an active form

Retinol: Retinol is the primary form of preformed vitamin

Retinal: Retinal is an intermediate form of vitamin A that plays a crucial role in vision. It is derived from retinol and is involved in the process of converting light into nerve signals in the retina, a key aspect of visual function.

Retinoic Acid: Is the primary active form of vitamin A. It is derived from retinol through oxidation processes in the body, primarily in the liver. Once converted into retinoic acid, it acts as a hormone-like compound that binds to retinoic acid receptors (RARs) and retinoid X receptors (RXRs) inside cells. It helps regulate gene expression and cellular processes. It plays essential roles in cell growth, differentiation, immune function, and skin health.

Retinyl Esters: Retinyl esters are storage forms of vitamin A found in animal-based foods and supplements. They are converted into retinol in the small intestine during digestion and serve as a reserve of vitamin A in the body.

Carotenoids: Carotenoids are pigments found in plants, algae, and certain bacteria. While not technically forms of vitamin A, some carotenoids have provitamin A activity, meaning they can be converted into retinol in the body. The most well-known carotenoid with provitamin A activity is beta-carotene. Other carotenoids like alpha-carotene, beta-cryptoxanthin, lutein, and zeaxanthin have antioxidant properties but are not efficiently converted into retinol.

Beta-Carotene: Beta-carotene is a provitamin A carotenoid found in orange and yellow fruits and vegetables, as well as dark leafy greens. The body can convert beta-carotene into retinol as needed. However, the conversion efficiency varies among individuals and is influenced by factors such as genetics and dietary habits.

In summary, vitamin A exists in various forms, including retinol, retinal, retinoic acid, retinyl esters, and provitamin A carotenoids like beta-carotene. Each form plays specific roles in vision, gene regulation, immune function, and overall health. Obtaining a mix of preformed vitamin A from animal-based sources and provitamin A carotenoids from plant-based foods contributes to meeting the body’s vitamin A needs and supporting optimal health.

Question 2

Vitamin D what are the active and storage form

Answer 2

Calcitrol is the active form and Cholecalciferol(D3) is the storage form in the skin

You’re correct that vitamin D3 (cholecalciferol) is indeed considered the active form of vitamin D in the body. Let’s clarify the different forms of vitamin D:

Vitamin D3 (Cholecalciferol): Vitamin D3 is synthesized in the skin when it’s exposed to sunlight (UVB radiation). It can also be obtained from dietary sources such as fatty fish, fish liver oils, egg yolks, and fortified foods. Once in the body, vitamin D3 undergoes hydroxylation in the liver to form 25-hydroxyvitamin D (calcifediol), which is considered the storage form of vitamin D. Further hydroxylation in the kidneys produces the active form, 1,25-dihydroxyvitamin D (calcitriol).

Vitamin D2 (Ergocalciferol): Vitamin D2 is derived from plant-based sources, such as fungi and yeast. It is less potent than vitamin D3 but can still be converted into the active form, calcitriol, in the body through similar hydroxylation processes.

Calcitriol (1,25-Dihydroxyvitamin D): Calcitriol is the biologically active form of vitamin D that regulates calcium and phosphorus levels, bone health, immune function, and various cellular processes. It is synthesized in the kidneys from 25-hydroxyvitamin D (calcifediol) produced in the liver. Calcitriol acts on vitamin D receptors (VDRs) in target tissues throughout the body to exert its effects.