Biomarkers: Current Projects

• A methodologic study is being carried out through the Eating at America's Table Study (EATS), which will examine how well various dietary assessment instruments estimate nutrient intake in relation to appropriate biomarkers. Two serum samples were obtained from a subset of 139 subjects in the EATS project who completed food frequency questionnaires and 24-hour dietary recalls. An additional 16 subjects provided only one serum sample. Serum carotenoids, tocopherols, and lipids were assessed for all subjects who provided at least one serum sample. The relation of these biomarkers with appropriate dietary estimates from three food frequency questionnaires and the dietary recalls will be evaluated.
  
  
• The Observing Protein and Energy Nutrition (OPEN) Study collected biomarkers of energy expenditure (doubly labeled water) and nitrogen, sodium, and potassium intakes (urinary nitrogen, sodium, and potassium) to assess the structure of measurement error in two self-reported dietary assessment instruments – 24-hour recalls and food frequency questionnaires (FFQs). Respondents were 484 adult men and women from suburban Washington, DC area. These data will be used to assess the degree of misreporting on both recalls and FFQs, as well as the ability of recalls to adjust for measurement error associated with FFQs.
  
  
• Staff have collaborated with the International Life Sciences Institute to produce a new monograph on Biomarkers of Nutritional Exposure and Status. This publication describes current knowledge for a variety of biomarkers and highlights future research directions.