Know your Hematocrit. Know your health.
Test your Hematocrit and 100+ other biomarkers in a single blood draw.
Normal range: 38.5 – 50 % (higher is better)
Hematocrit measures what percentage of your blood is made up of red blood cells versus plasma. It rises and falls alongside hemoglobin and RBC count. Low hematocrit points to anemia or blood loss. High hematocrit may suggest dehydration, smoking, or a bone marrow condition. Because it is a percentage, hematocrit can shift based on fluid status alone.
A normal Hematocrit is 38.5 – 50 %. Higher is better.
Low hematocrit has the same causes as low hemoglobin and RBC: iron deficiency, B12 or folate deficiency, chronic disease, blood loss, and bone marrow problems. Overhydration (excess IV fluids) can dilute the reading without actual red cell loss.
High hematocrit is most often from dehydration. Chronic causes include smoking, sleep apnea, living at high altitude, and testosterone or anabolic steroid use. Polycythemia vera, a rare bone marrow disorder, causes persistently elevated hematocrit.
The same dietary and lifestyle factors that support hemoglobin apply here: iron-rich foods, adequate B12 and folate, and staying well-hydrated. If you are dehydrated before a blood draw, hematocrit may look artificially high. Drinking water before your test gives a more accurate baseline.
Hematocrit is most highly correlated with Iron Saturation and Carbon Dioxide. Here are the top biomarkers correlated with Hematocrit, based on 500,000 tests done by Empirical Health.
The percentage shows how strongly two biomarkers move together. A higher number means the relationship is stronger. Green = rises and falls together. Orange = one rises as the other falls.
You can test your Hematocrit for $190 as part of Empirical's comprehensive health panel, which includes 100 biomarkers.
You can measure your Hematocrit for at 2,200+ testing locations across the US. Click below and enter your zip code to browse locations near you.
Test your Hematocrit and 100+ other biomarkers in a single blood draw.