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Sonja Y. Hess

Sonja Y. Hess

  • Associate Research Nutritionist, Department of Nutrition

3253 Meyer

(530) 752-1992



  • MSc, Food Science Engineering, Swiss Federal Institute of Technology Zurich, Switzerland, 1998
  • Ph.D. Human Nutrition, Swiss Federal Institute of Technology Zurich, Switzerland, 2003

Research Interests

Dr. Hess’ major research interests involve the design, implementation and evaluation of programs to control micronutrient deficiencies among children and women in low-income countries, and related issues of nutrient bioavailability, nutrient-nutrient interactions and nutritional assessment. The research program is generally carried out in the context of community-based intervention trials, using an efficacy or effectiveness study design.

Dr. Hess serves as Executive Officer of the International Zinc Nutrition Consultative Group whose objectives are to promote increased global awareness of the problem of zinc deficiency and implement activities to reduce or eliminate this problem.

Selected Publications

  • Abbeddou S, Hess SY, Yakes Jimenez E, Somé JW, Vosti SA, Guissou RM, Ouédraogo JB, Brown KH (2014). Comparison of methods to assess adherence to small-quantity lipid-based nutrient supplements (SQ-LNS) and dispersible tablets among young Burkinabé children participating in a community-based intervention trial. Maternal and Child Nutrition, 17 DEC 2014. doi: 10.1111/mcn.12162 [Epub ahead of print]. [PubMed]
  • Wessells KR, Hess SY, Ouédraogo ZP, Rouamba N, Ouédraogo JB, Brown KH (2014). Asymptomatic malaria infection affects the interpretation of biomarkers of iron and vitamin A status, even after adjusting for systemic inflammation, but does not affect plasma zinc concentrations among young children in Burkina Faso. Journal of Nutrition. Dec;144: 2050-8. doi: 10.3945/jn.114.200345. [Epub 2014 Oct 1]. [PubMed]
  • Hess SY, Brown KH, Sablah M, Engle-Stone R, Aaron GJ, Baker SK (2013). Results of Fortification Rapid Assessment Tool (FRAT) surveys in sub-Saharan Africa and suggestions for future modifications of the survey instrument. Food and Nutrition Bulletin, 34:21-38.[PubMed]
  • Wessells KR, Hess SY, Rouamba N, Ouédraogo ZP, Kellogg M, Goto R, Duggan C, Ouédraogo JB, Brown KH (2013). Associations between intestinal mucosal function and changes in plasma zinc concentration following zinc supplementation. Journal of Pediatric Gastroenterology and Nutrition, Sep;57(3):348-55. [PubMed]
  • Brown KH, Hess SY, Vosti SA, Baker SK (2013). Comparisons of the estimated cost-effectiveness of preventive and therapeutic zinc supplementation strategies for reducing child morbidity and mortality in sub-Saharan Africa. Food Nutrition Bulletin, 34:199-214. [PubMed]
  • Wilson SE, Ouédraogo CT, Prince L, Ouédraogo A, Hess SY, Rouamba N, Ouédraogo JB, Vosti SA, Brown KH (2012). Caregiver recognition of childhood diarrhea, care seeking behaviors and home treatment practices in rural Burkina Faso: a cross-sectional survey. PLOS ONE, 7(3):e33273 (pp 1-8). [PubMed]
  • Hess SY, Bado L, Aaron GJ, Ouedraogo JB, Zeilani M, Brown KH (2011) Acceptability of zinc-fortified, lipid-based nutrient supplements (LNS) prepared for young children in Burkina Faso. Maternal and Child Nutrition 7, 357-367. [PubMed]
  • Wuehler SE, Hess SY, Brown KH (2011) Situational analysis of infant and young child nutrition activities in the Sahel - Executive summary. Maternal and Child Nutrition 7, 1-5. [PubMed]
  • Wuehler SE, Hess SY, Brown KH (2011) Accelerating improvements in nutritional and health status of young children in the Sahel region of Sub-Saharan Africa: Review of international guidelines on infant and young child feeding and nutrition. Maternal and Child Nutrition 7, 6-34. [PubMed]
  • Baker S, Breyne C, Brown KH, Coulibaly-Zerbo F, David P, Diop M, Eijkenaar J, Fabre C, Fernandez JL, Hess SY, Hoorelbeke P, Horner A, Johnston R, Kupka R, Mulder-Sibanda M, Ndiaye B, Seidou B, Tchibindat F, Teixeira S, Wuehler SE (2011) The way forward: Repositioning children’s right to adequate nutrition in the Sahel. Maternal and Child Nutrition 7, 182-185. [PubMed]
  • Ba Lo N, Aaron GJ, Hess SY, Idohou Dossou N, Guiro AT, Wade S, Brown KH (2011) Plasma zinc concentration responds to short-term zinc supplementation but not zinc fortification in young children in Senegal. American Journal of Clinical Nutrition, Apr 13. [Epub ahead of print] [PubMed]
  • Aaron GJ, Ba Lo N, Hess SY, Guiro AT, Wade S, Brown KH (2011) Plasma zinc concentration increases within 2-weeks in healthy Senegalese men given liquid supplemental zinc, but not zinc-fortified wheat bread. Journal of Nutrition, May 11. [Epub ahead of print] [PubMed]
  • Gibbs M, Bailey KB, Lander RD, Fahmida U, Perlas L,  Hess SY, Loechl CU, Winichagoon P, Gibson RS (2011) The adequacy of micronutrient concentrations of manufactured complementary foods for low-income countries. Journal of Food Composition and Analysis 24, 418-426.
  • Wessells KR, Jorgensen J, Hess SY, Woodhouse L, Peerson JM, Brown KH (2010) The effects of initiation and discontinuation of short term zinc supplementation on the magnitude and velocity of change in plasma zinc concentrations. Journal of Nutrition 140, 2128-2133. [PubMed]
  • Hess SY (2010) The impact of common micronutrient deficiencies on iodine and thyroid metabolism: The evidence from human studies. Best Practice & Research Clinical Endocrinology and Metabolism 24, 117-132. [PubMed]
  • Hess SY, Lönnerdal B, Hotz C, Rivera JA, Brown KH (2009) Recent advances in knowledge on zinc nutrition and human health. Food and Nutrition Bulletin 30, S5-11. [PubMed]
  • Brown KH, Peerson JM, Baker S, Hess SY (2009) Preventive zinc supplementation among infants, pre-schoolers, and older pre-pubertal children. Food and Nutrition Bulletin 30, S12-40. [PubMed]
  • Hess SY, King JC (2009) Effects of maternal zinc supplementation on pregnancy and lactation outcomes. Food and Nutrition Bulletin 30, S60-78. [PubMed]
  • Hess SY, Brown KH (2009) Impact of zinc fortification on zinc nutrition. Food and Nutrition Bulletin 30, S79-107. [PubMed]
  • Brown KH, Hess SY, Boy E, Gibson R, Horton S, Osendarp S, Sempertegui F, Shrimpton R, Rudan I (2008) Setting priorities for zinc-related health research to reduce children’s disease burden worldwide: an application of the CHNRI research priority-setting method. Public Health Nutrition 12, 389-396. [PubMed]
  • Semba RD, de Pee S, Hess SY, Sun K, Sari M, Bloem MW (2008) Child malnutrition and mortality among families not utilizing adequately iodized salt in Indonesia. American Journal of Clinical Nutrition 87, 438-444. [PubMed]
  • Hess SY, Peerson JM, King J, Brown KH (2007) Use of serum zinc concentration as an indicator of population zinc status. Food and Nutrition Bulletin 28, S403-S429. [PubMed]
  • Brown KH, Wessells KR, Hess SY (2007) Zinc bioavailability from zinc-fortified foods. International Journal of Vitamin and Nutrition Research 77, 174-181. [PubMed]
  • Zimmermann MB, Winichagoon P, Gowachirapant S, Hess SY, Harrington M, Chavasit V, Lynch SR, Hurrell RF (2005) A comparison of the efficacy of wheat-based snacks fortified with ferrous sulphate, electrolytic iron, or hydrogen-reduced elemental iron: a randomized, double blind, controlled trial in Thai women. American Journal of Clinical Nutrition 82, 1276-1282. [PubMed]
  • Zimmermann MB, Ito Y, Hess SY, Fujieda K, Molinari L (2005) High thyroid volume in children with excess dietary iodine intakes. American Journal of Clinical Nutrition 81, 840-844. [PubMed]
  • Zimmermann MB, Molinari L, Staubli-Asobayire F, Hess SY, Chaouki N, Adou P, Hurrell RF (2005) Serum transferrin receptor and zinc protoporphyrin as indicators of iron status in African children. American Journal of Clinical Nutrition 81, 615-623. [PubMed]
  • Hess SY, Zimmermann MB (2004) The effect of micronutrient deficiencies on iodine nutrition and thyroid metabolism. International Journal for Vitamin and Nutrition Research 74, 103-115. [PubMed]
  • Zimmermann MB, Hess SY, Molenari L, de Benoist B, Delange F, Braverman L, Fujieda K, Ito Y, Jooste PL, Moosa K, Pearce EN, Pretell EA, Shishiba Y (2004) New reference values for thyroid volume by ultrasound in iodine-sufficient schoolchildren: A WHO/NHD IDD Study Group Report. American Journal of Clinical Nutrition 79, 231-237. [PubMed]
  • Zimmermann MB, Hess SY, Adou P, Torresani T, Wegmüller R, Hurrell RF (2003) Thyroid size and goiter prevalence after introduction of iodized salt: a 5-y prospective study in schoolchildren in Côte d'Ivoire. American Journal of Clinical Nutrition 77, 663-667. [PubMed]
  • Hess SY, Zimmermann MB, Adou P, Torresani T, Hurrell RF (2002) Treatment of iron deficiency in goitrous children improves the efficacy of iodized salt in Côte d'Ivoire. American Journal of Clinical Nutrition 75, 743-748. [PubMed]
  • Hess SY, Zimmermann MB, Arnold M, Langhans W, Hurrell RF (2002) Iron deficiency anemia reduces thyroid peroxidase activity in rats. Journal of Nutrition 132, 1951-1955. [PubMed]
  • Hess SY, Zimmermann MB, Torresani T, Bürgi H, Hurrell RF (2001) Monitoring the adequacy of salt iodization in Switzerland: a national study of school children and pregnant women. European Journal of Clinical Nutrition 55, 162-166. [PubMed]
  • Hess SY, Zimmermann MB, Brogli S, Hurrell RF (2001) A national survey of iron and folate status in pregnant women in Switzerland. International Journal for Vitamin and Nutrition Research 71, 268-273. [PubMed]
  • Zimmermann MB, Molinari L, Spehl M, Weidinger-Toth J, Podoba J, Hess S, Delange F (2001) Toward a consensus on reference values for thyroid volume in iodine-replete schoolchildren: results of a workshop on inter-observer and inter-equipment variation in sonographic measurement of thyroid volume. European Journal of Endocrinology 144, 213-220.
  • Hess SY, Zimmermann MB (2000) Thyroid volumes in a national sample of iodine-sufficient Swiss school children: comparison with the World Health Organization/International Council for the control of iodine deficiency disorders normative thyroid volume criteria. European Journal of Endocrinology 142, 599-603. [PubMed]
  • Zimmermann M, Saad A, Hess S, Torresani T, Chaouki N (2000) Thyroid ultrasound compared with World Health Organization 1960 and 1994 palpation criteria for determination of goiter prevalence in regions of mild and severe iodine deficiency. European Journal of Endocrinology 143, 727-731. [PubMed]