Challenges and Lessons Learned in Generating and Interpreting NHANES Nutritional Biomarker Data

Area of Science:

• Nutritional epidemiology
• Public health surveillance
• Laboratory science

Background:

• The National Center for Health Statistics has conducted nutrition surveillance for 45 years.
• NHANES collects anthropometric, dietary, and biomarker data to assess US population nutritional status.
• Biomarker testing has evolved to include a wide range of nutrients and bioactive compounds.

Purpose of the Study:

• To review challenges in measuring nutritional biomarkers within the NHANES program.
• To provide insights for researchers working with NHANES biomarker data.
• To emphasize the importance of data quality and interpretation in nutritional surveillance.

Main Methods:

• Review of the National Health and Nutrition Examination Survey (NHANES) biomarker data collection and analysis.
• Focus on the continuous NHANES (1999-present) using a "lessons learned" approach.
• Identification of key challenges in biomarker measurement, quality control, and interpretation.

Main Results:

• Challenges include using multiple biomarkers for single nutrients (e.g., folate, vitamin B-12, iron).
• Specimen collection and handling are critical for certain biomarkers (e.g., vitamin C, PUFAs, iodine).
• Quality control and study design (e.g., crossover studies) are essential for accurate trend assessment and method adjustment.

Conclusions:

• High-quality biomarker measurements are crucial for reliable nutritional status assessment.
• Addressing measurement challenges ensures the utility of NHANES data for public health.
• NHANES data informs comparisons of nutritional status, intervention impacts, and health-disease associations.