Micronutrient status, with special reference to vitamin B6

Area of Science:

• Nutritional biochemistry
• Human physiology
• Public health

Background:

• Micronutrient deficiencies pose public health challenges.
• Vitamin B6 is crucial for numerous metabolic processes.
• Assessing vitamin B6 status in the general adult population is important.

Purpose of the Study:

• To evaluate the adequacy of micronutrient status in adults.
• To specifically assess vitamin B6 status in relation to intake.
• To compare different biomarkers for their sensitivity to low vitamin B6 intake.

Main Methods:

• A random sample of 300 Dutch adults (20-79 years) served as a reference group.
• A separate group of 144 individuals with a documented low vitamin B6 intake was also studied.
• Micronutrient status was assessed using biochemical markers (plasma, erythrocyte, urinary levels) and functional tests (enzyme activities, homocysteine excretion, handgrip strength).

Main Results:

• Individuals with low vitamin B6 intake exhibited lower levels of key vitamin B6 metabolites (pyridoxal, pyridoxal-5'-phosphate) and impaired biochemical markers.
• Direct biomarkers of vitamin B6 status (plasma pyridoxal-5'-phosphate, urinary 4-pyridoxic acid) correlated well with functional parameters.
• The prevalence of inadequate vitamin B6, B2, B12, and C was generally below 7%, with a notable exception of 16% for low plasma pyridoxal-5'-phosphate in men aged 50-79.

Conclusions:

• Direct biomarkers effectively confirmed the low vitamin B6 intake in the selected group.
• Biomarker sensitivity for detecting low vitamin B6 status varied, with direct markers being most sensitive.
• Overall micronutrient adequacy was good, but specific subgroups, like older men, may require attention for vitamin B6 status.