β-Carotene vs Retinol: what is the difference?

How they differ

Beta-carotene is essentially two molecules of retinol joined tail to tail, which the body can cut in the gut wall to make vitamin A. That conversion is the entire difference. Retinol is preformed vitamin A from animal sources and is used directly, so it accumulates and can reach toxic levels; beta-carotene is converted only as needed, so surplus is stored in fat and skin rather than causing vitamin A toxicity. Eating a very large amount of beta-carotene turns skin orange, which is harmless and reversible. Beta-carotene is the orange of carrots and sweet potato and is nearly twice retinol's weight at 536.9 against 286.5. Conversion efficiency varies a great deal between people.

Side by side

Structural similarity 0.80 of 1, computed as a Morgan fingerprint Tanimoto coefficient. It measures shape, not effect.

Common questions

What is the difference between β-Carotene and Retinol?

Beta-carotene is essentially two molecules of retinol joined tail to tail, which the body can cut in the gut wall to make vitamin A. That conversion is the entire difference. Retinol is preformed vitamin A from animal sources and is used directly, so it accumulates and can reach toxic levels; beta-carotene is converted only as needed, so surplus is stored in fat and skin rather than causing vitamin A toxicity.

Is β-Carotene bigger than Retinol?

β-Carotene is the heavier molecule, 536.9 g/mol against 286.5 g/mol for Retinol. β-Carotene is C40H56 and Retinol is C20H30O.