Why ASH's New Guidelines Raise Ferritin Thresholds, With Jacquelyn Powers, MD, MS

Commonly used ferritin cutoffs miss many patients who are iron deficient and could benefit from treatment, according to the chair of the American Society of Hematology (ASH) panel behind the society's first guideline on diagnosing iron deficiency. To set new cutoffs, the panel compared thresholds population by population.

"The serum ferritin threshold of 15 was specifically chosen because that is the recommendation used by the World Health Organization, and then 30 was used because a lot of evidence suggests that 30 might be a more appropriate physiologic threshold," said Jacquelyn M. Powers, MD, MS, guideline chair, section chief of hematology at Texas Children's Hospital, and associate professor of pediatrics at Baylor College of Medicine, in an interview with HCPLive. "And then there is some data to suggest that certain patients feel better if you target a higher ferritin threshold of 50 or more, and that individuals continue to absorb iron up until their ferritin is 50."

The new guideline includes 5 recommendations developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. It recommends a serum ferritin threshold of ≤30 ng/mL for most adults, including menstruating and pregnant individuals, and ≤20 ng/mL for children aged 9 months to 4 years. These thresholds apply whether or not anemia is present.¹,²

Why ASH Prioritized Iron Deficiency Diagnosis Before Treatment

Each year, ASH asks its members to propose blood conditions that have new evidence but no existing guideline. Several years ago, members proposed guidance on diagnosing and treating iron deficiency, and ASH chose to prioritize it.

Iron deficiency affects patients from infancy to older adulthood, and many types of clinicians manage it. Powers noted that not all of those clinicians know the full range of signs and symptoms. She added that many commonly used lab values and thresholds miss a large number of patients who are iron deficient.

Because accurate identification has to come before treatment, the panel focused first on diagnosis, and specifically on serum ferritin. It is the most commonly used test for iron deficiency and serves as a marker of the body's iron stores. ASH expects to release treatment guidance in 2027.²

Comparing Ferritin Thresholds of 15, 30, and 50 ng/mL Across Populations

For adults who are not menstruating or pregnant, pregnant individuals, and menstruating adolescents and adults, the panel compared ferritin thresholds of 15, 30, and 50 ng/mL. These are the thresholds where most of the evidence on diagnostic accuracy, treatment response, and symptoms is concentrated.

The panel evaluated each threshold separately for each group. The prevalence of iron deficiency and the needs of patients differ across populations, so a new cutoff could have a different effect in each group. For adults with inflammation, the guideline recommends a ferritin <100 ng/mL or a transferrin saturation <20%.¹

Why Young Children Need a Separate Ferritin Threshold

"That's not because children have less iron needs necessarily, but because they're going through a rapid period of growth," Powers said. "They're really using that iron much more actively compared to adult populations, and so it's just kind of a different phase of life physiologically, how they're using that iron."

For young children, the panel compared ferritin thresholds of 12 ng/mL, the World Health Organization cutoff, and 20 ng/mL. Powers explained that some data suggest children continue to absorb iron until ferritin reaches about 20 ng/mL, after which absorption may plateau. The guideline recommends ≤20 ng/mL for this age group.¹

Editor's Note: Powers reported no relevant disclosures.

References

1. Powers JM, Lim MY, Achebe MO, et al. American Society of Hematology 2026 guidelines for diagnosis of iron deficiency. Blood Adv. 2026. doi:10.1182/bloodadvances.2025015950

2. American Society of Hematology. ASH sets new standards for diagnosing iron deficiency. Medical Xpress. September 16, 2026. https://medicalxpress.com/news/2026-09-ash-standards-iron-deficiency.html