Executive Summary

Background

Knowledge about biochemical indicators helps health experts make diet and nutrition recommendations to address disease and improve health. The CDC Nutrition Report is part of a series of publications that provide ongoing assessment of the U.S. population's nutrition status. This report helps with assessment by measuring indicators in blood and urine.

Inside the report

The report presents information on 131 biochemical indicators in the U.S. population. CDC scientists measured these levels in the blood and urine of people who participated in CDC's National Health and Nutrition Examination Survey (NHANES) between 1999 and 2023. The information is presented by age, sex, and race and Hispanic origin.

Some of the indicators used in this report include

• Water-soluble vitamins (compounds that can dissolve in water), such as folate, vitamins B6, B12, and C
• Fat-soluble vitamins and nutrients (compounds that can dissolve in fat), such as vitamins A, E, and D; carotenoids; and fatty acids (saturated, monounsaturated, and polyunsaturated)
• Trace elements (dietary minerals that are needed in very small quantities) such as iron and iodine
• Isoflavones and lignans (natural compounds found in certain plant foods)
• Acrylamide hemoglobin adducts (chemical compounds formed when certain starchy foods are cooked at high temperatures and react with hemoglobin)
• Trans-fatty acids (unsaturated fats found naturally in some animal products and artificially in partially hydrogenated oils)

Access the comprehensive list of indicators covered in the CDC Nutrition Report in Appendix B.

Purpose of the CDC Nutrition Report

This report informs health scientists and policy makers about the levels of biochemical indicators of diet and nutrition. It focuses on the U.S. population and on selected population groups such as children and women of childbearing age. These data help healthcare providers, scientists, and public health officials assess whether there is inadequate or excess nutritional intake. The report also helps

• Establish or improve data that are used to determine if a person or a group has an unusually high or low level of a nutrition biochemical indicator (population reference level)
• Determine if the nutrition status of population groups—such as minorities, children, women of reproductive age, or the elderly—differs from other groups and if the nutrition status needs improvement
• Detect significant trends in nutrition levels
• Assess whether public health efforts to enhance the diet and nutrition of the U.S. population are working
• Guide future research in nutrition and health

Interpreting the data

The measurements presented in this report are the result of cumulative intakes from

• Foods, some fortified with micronutrients (e.g., iron, thiamin, riboflavin, niacin, folate, vitamin A, vitamin D)
• Dietary supplements that contain vitamins, minerals, or both

Biochemical indicators measured in blood and urine can also be influenced by factors other than diet, such as various diseases.

This report presents reference information on selected biochemical indicators. Differences between population subgroups can be assessed by identifying groups with non-overlapping confidence intervals. A confidence interval is a range around a measurement that conveys how precise the measurement is.

It is beyond the scope of this report to explore the reasons for differences in observations derived from descriptive analyses. Also, the study design does not permit CDC to estimate biochemical indicators by state or by city. For example, CDC cannot extract a subset of data and examine levels of folate in a particular state or city.