It has the effect of eliminating peroxide radicals produced by protophyrin when exposed to sunlight. In the human body, betacarotene releases two molecules of vitamin A through the action of oxidase, thereby exerting the effect of vitamin A.

Vitamin A has various physiological functions such as promoting growth and reproduction, maintaining bones, epithelial tissues, vision, and normal secretion of mucosal epithelium. Vitamin A and its analogues can prevent precancerous lesions.

The classic or earliest recognized function of vitamin A is to participate in maintaining the circulation of photosensitive substances for scotopic vision in visual cells. The rod cells on the retina contain rhodopsin, which is composed of 11-cis retinal combined with opsin, and is sensitive to dark light. After rhodopsin is exposed to light, 11-cis-retinal is converted into all-trans retinal and separated from the opsin, producing visual electrical signals.

The dissociated all-trans retinal is reduced to all-trans retinol in rod cells and transported to the retinal pigment epithelial cells, where it combines with all-trans retinol from plasma. Together, the complex isomerization process begins, participating in the supply of 11-cis-retinal required for the resynthesis of rhodopsin, and maintaining dark light adaptation.

Therefore, to maintain good dark-light vision, it is necessary to continuously supply sufficient 11-cis-retinal to rod cells. When vitamin A is deficient, the supply of 11-cis-retinal is reduced and the dark adaptation time is prolonged.

Extended information

Betacarotene precautions:

1. Use with caution in those with severe liver and kidney damage.

2. Most of the effects of this product appear within 2-6 weeks after taking the medicine. If no effect is seen after 6 weeks, the dose can be appropriately increased until the skin of the palms becomes yellowish, and then the dosage can be gradually reduced.

3. It is forbidden for those who are allergic to this product.

Reference: Baidu Encyclopedia - Betacarotene