Repletion and depletion of serum alpha and beta carotene in humans with carrots and an algae-derived supplement.

ABSTRACT

A 10-day low-carotene diet phase (LCD), followed by a 7-day treatment phase (TP) and then another LCD, was adhered to by 32 adult human subjects. Serum alpha carotene (SAC) and serum beta carotene (SBC) levels were examined using HPLC and found to have decreased 44.7% and 35.8% respectively in the first LCD. Alpha and beta carotene, from algae-derived capsules and raw carrots, significantly increased SAC and SBC levels during the TP. Half-lives of SAC and SBC averaged 7.8 days and 12.4 days respectively during the two LCD. Serum vitamin A remained unchanged throughout the study.