From the Research
Chronic heavy smokers typically have elevated hematocrit and hemoglobin levels compared to non-smokers, with average hematocrit levels around 41.4% and hemoglobin levels around 16-18 g/dL, as seen in a study published in 2018 1. The elevation in hematocrit and hemoglobin levels in chronic heavy smokers is a compensatory mechanism to maintain oxygen delivery to tissues despite the reduced efficiency of each hemoglobin molecule due to carbon monoxide binding. Some key points to consider include:
- The average hematocrit for a chronic heavy smoker is approximately 45-52% for men and 42-49% for women, while the average hemoglobin is around 16-18 g/dL for men and 15-17 g/dL for women, as supported by a study published in 2017 2.
- These values are generally 1-3 percentage points higher for hematocrit and 1-2 g/dL higher for hemoglobin than in non-smokers.
- A study published in 2020 found that smokers had significantly higher levels of red blood cells, hematocrits, hemoglobin levels, and other parameters compared to non-smokers 3.
- Another study published in 2009 found that heavy smokers had significantly higher mean haemoglobin levels than non-smokers, with a positive correlation between number of cigarettes/day and haemoglobin concentrations 4. However, it's essential to note that these elevated levels also increase blood viscosity, which can contribute to cardiovascular risks associated with smoking. The most recent and highest quality study, published in 2018, found that current smoking was independently positively associated with hematocrit levels and hemoglobin levels, but inversely associated with EPO levels 1. These findings suggest that chronic heavy smoking has a significant impact on hematocrit and hemoglobin levels, and healthcare providers should be aware of these changes when interpreting laboratory results for smokers.