Human requirements and needs. Vitamin C status: methods and findings

Area of Science:

• Biochemistry
• Human Nutrition
• Clinical Diagnostics

Background:

• Assessing vitamin C nutritional status traditionally relies on dietary intake and clinical signs.
• Biochemical measurements provide a more objective evaluation of vitamin C adequacy.
• Previous methods for assessing vitamin C status included measuring ascorbate in serum, leukocytes, blood, and urine.

Purpose of the Study:

• To review objective biochemical methods for assessing vitamin C nutritional status.
• To highlight the practicality and common use of serum ascorbate measurements.
• To discuss the utility of leukocyte and urinary ascorbate levels, and vitamin C loading tests in specific clinical contexts.

Main Methods:

• Review of biochemical procedures for measuring ascorbic acid in biological samples.
• Discussion of automated and manual colorimetric and fluorometric assays.
• Analysis of data from nutrition surveys in Canada and the United States.

Main Results:

• Serum ascorbate measurement is the most common and practical method for assessing vitamin C status in individuals and populations.
• Leukocyte ascorbate levels offer insights into body stores but are technically challenging.
• Urinary ascorbate levels and vitamin C loading tests can aid in scurvy diagnosis.
• Nutrition surveys indicate vitamin C deficits in certain population groups in Canada and the US.

Conclusions:

• Biochemical assessments, particularly serum ascorbate levels, are crucial for objective vitamin C status evaluation.
• While other methods exist, serum analysis remains the most practical for widespread use.
• Identified vitamin C deficits highlight the need for continued nutritional monitoring and intervention.