What Hemoglobin (Hb) and Hematocrit (Hct) values are significant?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: June 27, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Significant hemoglobin (Hb) and hematocrit (Hct) values are those that indicate anemia or polycythemia, with Hb below 11 g/dL (Hct 33%) and above 12 g/dL (Hct 36%) being critical thresholds for adults, as evidenced by studies such as 1.

Key Points:

  • For adults, hemoglobin levels below 11 g/dL (Hct 33%) are associated with increased morbidity and mortality, while levels above 12 g/dL (Hct 36%) are generally considered adequate 1.
  • The target range for hemoglobin (hematocrit) should be Hgb 11 g/dL (33%) to Hgb 12 g/dL (36%), as recommended by clinical practice guidelines for anemia in chronic kidney disease 1.
  • Hemoglobin levels below 10 g/dL (Hct 30%) are associated with worse patient outcomes, including increased risk of left ventricular hypertrophy, decreased quality of life, and higher mortality rates 1.
  • Anemia is a significant factor in various conditions, including heart failure, renal failure, and malignancy, and its diagnosis and treatment are crucial for improving patient outcomes 1.
  • Hemoglobin and hematocrit values vary by age, sex, and clinical context, and must be interpreted in light of these factors to ensure accurate diagnosis and treatment of anemia or polycythemia 1.

From the Research

Hemoglobin (Hb) Values

  • The World Health Organization (WHO) defines anemia as Hb levels <12.0 g/dL in women and <13.0 g/dL in men 2, 3
  • New lower limits of normal Hb values have been proposed, according to ethnicity, gender, and age 2
  • Hb levels <12 g/dL in both sexes are considered anemic in the elderly population 2
  • Hb concentrations <13 g/dL for men and <12 g/dL for women are defined as pernicious anemia (PA) by the WHO 3
  • Normal Hb values for healthy persons living at high altitude (4000 meters) are:
    • Men: 13-21 g/dL
    • Women: 12-19 g/dL 4
  • Hb levels between 4 gm% and 11 gm% are considered severe anemia in patients with menorrhagia 5
  • An Hb level of 12-13 g/dL may be appropriate for some chronic kidney disease patients, depending on the individual patient and ESA dose 6

Hematocrit (Hct) Values

  • Normal Hct values for healthy persons living at high altitude (4000 meters) are:
    • Men: 45-61%
    • Women: 41-56% 4
  • Hct values above 61% in men or 56% in women are considered outside the normal range 4

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Do all the patients with vitamin B12 deficiency have pernicious anemia?

Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology, 2016

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.