Vitamin C disposition in young and elderly men

Area of Science:

• Biochemistry
• Human Physiology
• Nutritional Science

Background:

• Vitamin C (ascorbic acid) is essential for numerous bodily functions.
• Understanding its pharmacokinetics is crucial for determining optimal intake and therapeutic strategies.
• Age-related changes in physiology could potentially influence vitamin C metabolism.

Purpose of the Study:

• To compare the pharmacokinetics of vitamin C in young versus elderly healthy men.
• To investigate the influence of vitamin C nutritional status (depleted vs. supplemented) on its pharmacokinetics.
• To determine if age or nutritional status is a more significant factor in vitamin C pharmacokinetics.

Main Methods:

• 15 healthy young men and 15 healthy elderly men were enrolled.
• Subjects were studied in two states: vitamin C-depleted (diet <10 mg/d for 4-5 weeks) and vitamin C-supplemented (500 mg/d for 3 weeks).
• Pharmacokinetics were assessed after a single 500-mg oral vitamin C tablet dose, with plasma and urine samples collected for up to 72 hours.

Main Results:

• Several pharmacokinetic indices differed significantly between vitamin C-depleted and supplemented subjects.
• No significant age-related differences in any measured pharmacokinetic indices were observed.
• Vitamin C nutritional status demonstrably influences vitamin C pharmacokinetics.

Conclusions:

• Vitamin C nutritional status is a key determinant of vitamin C pharmacokinetics.
• Age does not appear to be a significant factor influencing vitamin C pharmacokinetics in healthy adult males.
• These findings highlight the importance of maintaining adequate vitamin C status for optimal vitamin C utilization.