Assessment of nutritional and micronutrient status Wolfgang Stütz Institute of Biological Chemistry and Nutrition University of Hohenheim Scale-N Kickoff-Meeting, January 2016, Morogoro

Assessment of nutritional/micronutrient status by Anthropometry: weight, height, BMI ‘Stunting’: height for age" value to be less than two standard deviations of the WHO Child Growth Standards median Dietary intake (24 hour recall, food frequency) of macro- and micronutrients (proteins, fat, vitamins) Questionnaires on clinical symptoms for deficiencies Analysis of macro- and micronutrients (MNs) in blood Biological monitoring: detailed assessment to control an intervention / nutrition program (e.g. Scale-N)

Minerals and trace elements Macronutrients Micronutrients Vitamins Minerals and trace elements carbohydrates glucose fat fat acids triglycerides cholesterol protein albumin amino acids water soluble vitamin B1 vitamin B2 vitamin B6 vitamin B12 vitamin C folate fat soluble vitamin A vitamin D vitamin E vitamin K sodium potassium calcium magnesium iron copper iodine fluorine manganese selenium zinc

Main ‚important‘ micronutrients (MNs) essential for manifestation of its deficiency indicator cut off value Iron hemoglobin, many enzymes anemia, reduced growth, impaired development serum ferritin < 12 µg/L < 30 µg/L Vitamin A eyes / vision immune system xerophthalmia immune deficiency serum retinol < 0.7 µmol/L < 1.05 µmol/L Zinc Growth retardation, immune deficiency serum zinc < 10.7 µmol/L (0.7 mg/L)

Specimen and Methods to analyse MNs / MN status in Food: iron, pro-vitamin A, zinc in fruits, vegetables, corn Blood: iron, vitamin A, zinc in serum/plasma; hemoglobin in whole blood Direct measurement of MNs: vitamin A (retinol) and carotenoids (HPLC), iron, zinc (AAS or ICP-MS) Indirect measurement: hemoglobin (iron status) and transport proteins in blood retinol binding protein (RBP)  vitamin A status ferritin, soluble transferrin receptor (sTfR)  iron status HPLC: high performance liquid chromatography: vitamin A, carotenoids, vitamin E AAS: atomic absorption spectrophotometry: zinc, iron, ICP- MS: inductively coupled plasma – mass spectrometry: zin, iron ELISA: enzyme-linked immuno (sorbent) assay: antibodies (RBP, ferritin, sTfR) Spectro-photometry: also in connection with other techniques (HPLC)

Assessment of Iron status Hemoglobin - Hb or hematocrit - Hct (packed cell volume: % x 3.33 ≈ Hb ) Anemia: Hb < 120 g/L (< 110 g/L pregnant women, children) < 70 g/L severe anemia Serum Ferritin (SF): transport protein reflecting iron storage SF < 12 µg/L - depleted iron stores SF < 30 µg/L - depleted iron stores during infections SF is affected by infections: ↑ if acute phase protein CRP or AGP ↑ CRP: C-reactive protein (acute infections) AGP: alpha 1-glycoprotein (‚persistant‘ infections) Soluble Transferrin Receptor (sTfR): reflecting tissue iron storage sTfR > 8.5 mg/L - iron deficiency Iron deficiency anemia (IDA): anemia and iron deficiency e.g. Hb < 120 g/L and SF <12 µg/ L and/or sTfR > 8.5 mg/L hemoglobin/hct ↓ serum ferritin ↓ soluble transferrin receptor ↑ MNs responsible for anemia: iron, folic acid, vitamin B12, vitamin A

Assessment of vitamin A and zinc status Serum / plasma retinol: normal range 0.7 - 1.75 µmol/L vitamin A deficiency (VAD): retinol < 0.7 µmol/L (< 20 µg/dL) severe VAD: < 0.35 µmol/L (night blindness) subclinical VAD: 0.35 - 0.70 µmol/L (10 - 20 µg/dL) low vitamin A status : < 1.05 µmol/L (< 30 µg/dL) RBP - retinol binding protein (ELISA): highly correlated to plasma retinol Pro-vitamin A- carotenoids: α-/β-carotene, β-cryptoxanthin Zinc in plasma: normal range >0.7 mg (10.7 µmol/L)

Retinol,  -tocopherol, and  -carotene in food or blood by high performance liquid chromatography (HPLC) 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 min -1000 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 uV ß-Cryptoxanthin Oxim α-, ß- Carotene Retinol Lycopene Lutein Zeaxanthin Retinol at 325 nm Carotenoids at 450 nm Tocopherols EX/EM 298/328 nm 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 min -2500 2500 5000 7500 10000 12500 15000 17500 20000 22500 uV γ-,α- Tocopherol

Budget for hemoglobin and MN analysis € per Unit N Units Total € Carotenoids , retinol and vitamin E in food (HPLC) 10 750 7500 Vitamin C in food 6 4500 Iron and zinc in food (ICP-MS) 4 3000 15000 Hemoglobin 1 1200 + 2100 Ferritin, soluble transferrin receptor CRP (C-recative protein) AGP (α-1 glycoprotein) RBP - Retinol Binding Protein 2 x 600 1200 (2400) Transport to Germany 2 Carotenoids, Vitamin A, E in plasma 12000 (24000)

Nutritional Surveys: baseline and after ‚intervention‘ June 2016 Measurement Method House-holds Number (n) Dietary intake FFQ and 24 h Recall 4 x 150 600 Anthropometry Weight (kg) and height (cm) > 600 Blood MNs Mother infant pairs: Iron status (ferrritin, sTfR), vitamin A (RBP, vitamin A, carotenoids) 1200 MNs in food (vegetables, fruits) Iron, zinc, carotinoids (vitamin A) ??? Nutritional Survey June 2018