Global Data Visualizations

The proportion of the population with deficiency in folate, iron, vitamin A, vitamin B12, and zinc.

This interactive map provides the percentage of the population with deficiencies in folate, iron, vitamin A, vitamin B12, and zinc. For information on iodine status, please visit this visualization.

This visualization can help identify specific population groups with micronutrient deficiencies and areas of public health concern. The information provided here can help guide improvements to existing fortification programs, introduction of new food vehicles to be fortified, addition of new nutrients to existing fortification vehicles, or strengthening other programs that deliver micronutrients.

For each nutrient, there are 1 to 3 indicators measured in individuals’ blood to determine population nutrient status.

Indicators Used for Each Nutrient

• Folate: (1) Plasma or serum folate; (2) Red blood cell folate
• Iron: (1) Plasma or serum ferritin; (2) Serum transferrin receptor; (3) Iron-deficiency anemia
• Vitamin A: (1) Plasma or serum retinol; (2) Retinol binding protein
• Vitamin B12: Plasma or serum vitamin B12
• Zinc: Plasma or serum zinc

For all nutrients included in this visualization, higher deficiency prevalence indicates a greater nutritional problem in the population.

Iron deficiency severity (WHO 2020)

• Less than or equal to 4.9%: No public health problem
• 5.0% to 19.9%: Mild public health problem
• 20.0% to 39.9%: Moderate public health problem
• Greater than or equal to 40.0%: Severe public health problem

Interpreting iron status using ferritin and transferrin receptor (WHO 2014)

• If low ferritin is less than 20% AND high transferrin receptor is less than 10%, iron deficiency is not prevalent.
• If low ferritin is less than 20% AND high transferrin receptor is 10% or greater, iron deficiency is prevalent and inflammation is prevalent.
• If low ferritin is 20% or greater AND high transferrin receptor is 10% or greater, iron deficiency is prevalent.
• If low ferritin is 20% or greater AND high transferrin receptor is less than 10%, iron deficiency is prevalent.

Vitamin A deficiency severity (WHO 2011)

• Less than 2.0%: No public health problem
• 2.0% to 9.9%: Mild public health problem
• 10.0% to 19.9%: Moderate public health problem
• 20.0% or greater: Severe public health problem

1. Click on the “Data” tab at the bottom of the visualization window.
2. Hover over the header row of the table until three dots appear.
3. Click “More options.”
4. Select “Export data.”
5. Choose your desired format (Excel or CSV) and click “Export.”

• Across biomarkers used in GFDx, deficiency is generally indicated by low concentrations in individuals or populations, with the exception of transferrin receptor, where higher levels indicate iron deficiency.

Using an application programming interface (API) from the World Health Organization, GFDx imports the following data from the Vitamin and Mineral Nutrition Information System:

• Population group: The group with data in this visualization, such as infants, school-age children, adolescents, pregnant women, women of reproductive age, men, and the elderly
• Nutrient: The micronutrients with data in this visualization; specifically, folate, iron, iodine, vitamin A, vitamin B12, and zinc.
• Indicator: The biomarker measured in individuals’ blood or urine to determine nutrient status in the population group. For example, there are two indicators for folate: (i) plasma or serum folate, and (ii) red blood cell folate.
• Percent with deficiency: The percent of the population with deficiency for the indicators’ plasma or serum folate, red blood cell folate, transferrin, transferrin receptor, plasma or serum retinol, retinol binding protein, plasma or serum vitamin B12 and plasma or serum zinc.

For more information about GFDx methodology and indicators: GFDx Data Dictionary.

The data populating this visualization are from the World Health Organization’s Vitamin and Mineral Nutrition Information System (VMNIS).

• WHO, 2011: Serum retinol concentrations for determining the prevalence of vitamin A deficiency in populations.
• WHO, 2014: Serum transferrin receptor levels for the assessment of iron status and iron deficiency in populations.
• WHO 2020. Guideline on use of ferritin concentrations to assess iron status in individuals and populations.
• WHO, 2020: Serum and red blood cell folate concentrations for assessing folate status in populations.

Global Fortification Data Exchange. Map: Micronutrient deficiency prevalence estimates by country. Accessed dd/month/yyyy. [http://www.fortificationdata.org.]