See also Fat soluble vitamins
Zinc and vitamin A interact in several ways. Zinc is a component of retinol-binding protein, a protein necessary for transporting vitamin A in the blood. Zinc is also required for the enzyme that converts retinol (vitamin A) to retinal. This latter form of vitamin A is necessary for the synthesis of rhodopsin, a protein in the eye that absorbs light and thus is involved in dark adaptation. Zinc deficiency is associated with decreased release of vitamin A from the liver, which may contribute to symptoms of night blindness that are seen with zinc deficiency
So a zinc deficiency may really mean a vitamin A deficiency in some cases. On the other hand, it might also be that you have symptoms of a vitamin A deficiency when in fact, you’re having a zinc deficiency.
- Low zinc, low vitamin A: symptoms of both zinc and vitamin A deficiency.
- Low zinc, normal vitamin A: symptoms of both zinc and vitamin A deficiency, because the low zinc prevents the vitamin A from doing its job.
- Normal zinc, low vitamin A: symptoms of a vitamin A deficiency (night blindness, rough skin), but not of zinc deficiency (white spots on nails, feeling drowsy).
It might be difficult to find out what deficiency is causing your problems.
Vitamins A and D support the absorption of zinc and zinc supports the absorption of all the fat-soluble vitamins.