Do Global Dietary Nutrient Datasets Associate with Human Biomarker Assessments? A Regression Analysis

Area of Science:

• Global nutrition research
• Nutritional epidemiology
• Public health policy

Background:

• Nationally representative biomarker assays are the gold standard for assessing global nutrition but are costly and difficult to implement.
• Global nutrient datasets, measuring nutrients provided by diet, are frequently used as proxies due to broader coverage, despite questionable accuracy.
• The reliability of these dietary nutrient datasets as indicators of actual nutritional status is a significant concern for global health assessments.

Purpose of the Study:

• To evaluate the association between estimates of inadequate dietary intake from global nutrient datasets and actual biophysical deficiencies measured by biomarkers.
• To determine if commonly used global nutrient datasets accurately reflect nutritional status in vulnerable populations.

Main Methods:

• Linear regressions were used to compare inadequate dietary nutrient intake estimates from three global datasets (Global Dietary Database, Global Nutrient Database, GENuS model) with biomarker data.
• The analysis focused on three key nutrients: zinc, folate, and vitamin A.
• Two vulnerable groups were assessed: females of childbearing age and children under 5 years.

Main Results:

• Only 3 out of 22 regressions showed significant associations (P < 0.1) between global nutrient datasets and biophysical deficiency.
• Reliable associations were found for zinc in females of childbearing age (GENuS, Global Dietary Database) and children under 5 years (GENuS).
• Folate and vitamin A exhibited no consistent relationship between dataset estimates and biomarker data; estimated global zinc deficiency ranged from 31%-37%.

Conclusions:

• Global dietary nutrient datasets demonstrate limited association with direct biomarker measures of nutritional deficiency.
• Caution is advised when utilizing global nutrient datasets for global health research and policy decisions.
• Findings suggest that global nutrient datasets have restricted applications and should be used judiciously, especially for folate and vitamin A assessments.