About

Kimberly O'Brien is a Professor of Human Nutrition in the Division of Nutritional Sciences at Cornell University. She received her B.S. in Biology from the University of New Hampshire and her Ph.D. in Nutrition from the University of Connecticut, Storrs. Her professional training includes fellowships with the National Institute of Child Health and Human Development, the Laboratory of Theoretical and Physical Biology/Section for Metabolic Analysis and Mass Spectrometry, and the Children’s Nutrition Research Center at Baylor College of Medicine. Prior to her current position, she worked for ten years as a faculty member in the Center of Human Nutrition at Johns Hopkins Bloomberg School of Public Health. Professor O'Brien's research centers on understanding mineral metabolism and bone health in infants, children, and pregnant and lactating women in both developed and developing countries. Her work addresses issues of calcium metabolism through metabolic studies involving groups such as children from osteoporotic families, pregnant and lactating adolescents, and children with chronic diseases like cystic fibrosis and HIV infection. Her current research focuses on the impact of adolescent pregnancy among minority populations on maternal and fetal bone health, risk of anemia, and maternal and neonatal vitamin D and iron physiology. She investigates nutrient partitioning between mother and fetus at the cellular level by assessing placental mineral transporters in relation to maternal and neonatal status. To facilitate kinetic studies of human mineral metabolism, she has established a mass spectrometry laboratory equipped for high-sensitivity mineral stable isotope analysis, which collaborates with other academic institutions.

Selected publications

• Differential associations between menstrual blood loss scores and iron status in East Asian and Northern European individuals: findings from a cross-sectional analysis of the Iron Genes in East Asian and Northern European Adults Study (FeGenes) cohort

  American Journal of Clinical Nutrition · 2026-04-25

  articleSenior authorCorresponding
  PublisherDOI

• A genetic association study of iron absorption in adults of East Asian or Northern European ancestry from the Iron Genes in East Asian and Northern European Adults Study (FeGenes)

  American Journal of Clinical Nutrition · 2026-03-26

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Impact of Hormonal Contraceptives on Iron (Fe) Status in Females of Reproductive Age

  Current Developments in Nutrition · 2025-05-01

  articleOpen accessSenior author
  PublisherDOI

• Unilateral Absence of the Psoas Major and Iliacus Muscles and Downstream Effects of Surgical Intervention in a 96 year-old Female Donor

  International Journal of Cadaveric Studies and Anatomical Variations · 2025-06-27

  articleOpen access

  Learning anatomy through donor dissection allows students the unique opportunity to explore variations in anatomical structures which may include or indicate pathological anomalies. Findings could reveal insights into the life of the donor, along with the downstream effects of clinical intervention. This case study discusses the findings of a group of first-year medical students during a full body dissection of a 96-year-old female. Among other anomalies, evidence of drastic surgical intervention, extreme scoliosis, and muscle atrophy were noted. Findings suggest that the donor’s right psoas major and iliacus muscles were removed, likely as part of a surgical resection of a retroperitoneal tumor. Distal to the resected muscles, notable muscle atrophy with fat infiltration in the anterior right thigh muscles suggests muscle wasting, which could be secondary to the removal of these muscles. In addition, extreme scoliosis was discovered, likely attributed to the imbalance in hip flexor muscles following surgical removal of the iliopsoas muscle. The theorized surgical removal of iliopsoas muscles along with the downstream effects of muscle atrophy and severe scoliosis depict the impact surgical intervention can have on a patient’s quality of life. Anatomical findings of the donor discovered during dissection and theorized surgical interventions based upon gross findings are discussed in detail within this case.

  PublisherOA PDFDOI

• Double-Chambered Right Ventricle

  CSurgeries · 2025-01-01

  article1st authorCorresponding
  PublisherDOI

• Impact of Plant-Based vs. Omnivorous Diets: Iron absorption and Gut Microbiota Interactions

  Current Developments in Nutrition · 2025-05-01

  articleOpen access
  PublisherDOI

• Characterization of iron status biomarkers and hematological indices among young adults of East Asian or Northern European ancestry: A cross-sectional analysis from the Iron Genes in East Asian and Northern European Adults Study (FeGenes)

  American Journal of Clinical Nutrition · 2025-02-01 · 5 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Iron regulatory hormones and their associations with iron status biomarkers among healthy adults of East Asian or Northern European ancestry: A cross-sectional comparison from the Iron Genes in East Asian and Northern European Adults Study (FeGenes)

  American Journal of Clinical Nutrition · 2025-02-01 · 5 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Dietary intake in East Asian and Northern European participants from the FeGenes study

  European Journal of Nutrition · 2025-06-05 · 3 citations

  articleSenior author
  PublisherDOI

• Menstrual Characteristics and Iron Status in Northern European and East Asian Individuals

  Current Developments in Nutrition · 2025-05-01

  articleOpen accessSenior author

  from fat), or 4) HFD + 5% FOS (HFD-FOS) for 10 weeks.Serum and colonic mucosa were collected for analyses of VD signaling and pro-inflammatory cytokines.Results: Body weight of HFD mice was 1.6-fold greater than in CON mice after 10-week of intervention (P < 0.001), yet FOS did not alter body weight in mice fed either diet.HFD mice exhibited lower VD status (P 0.037), as measured by serum 25hydroxycholecalciferol (25D), and 70% lower in colonic Vdr mRNA expression (P 0.038) compared to CON mice.Though FOS did not affect serum 25D levels in either CON or HFD mice, mRNA expression of colonic Vdr was upregulated by 2-fold in mice of HFD-FOS compared to HFD (P < 0.01).A lowering trend was observed with mRNA expression of colonic Toll-like receptor 4 (Tlr4) in HFD-FOS mice compared to HFD mice (P 0.068), which was negatively correlated to colonic Vdr expression (r -0.747; P < 0.01).Additionally, FOS suppressed the elevation of circulating IL-6 by 44% in HFD mice (P 0.038), and that it did not differ from CON mice.Conclusions: We showed that FOS suppressed VDR activation in the colon and attenuated colonic inflammation in HFDinduced obese mice possibly via the inhibition of TLR4 signaling pathway.Taken together, FOS may serve as a potential dietary intervention for the prevention of gastrointestinal complications associated with obesity phenotype.

  PublisherOA PDFDOI

Labs

• Kimberly O'Brien LaboratoryPI

Awards & honors

• NRSA Fellowship, Baylor College of Medicine (1995)
• IRTA Fellowship, National Institutes of Health (1993)