What Causes Thick Blood?

The term “thick blood” is not a medical diagnosis, but it is sometimes used informally to describe various conditions or factors that can affect blood viscosity (thickness). Blood viscosity is primarily determined by the concentration of blood cells and the level of plasma proteins in the bloodstream. Several medical conditions and factors can influence blood thickness, including:

  • Dehydration: When you’re dehydrated, your body may not have enough fluid to maintain normal blood volume. This can lead to an increase in blood viscosity because there is less water in the bloodstream.
  • Polycythemia: Polycythemia refers to an increase in the number of red blood cells in the blood. This can occur due to various reasons, including certain medical conditions (such as polycythemia vera), smoking, high altitudes, or chronic hypoxia (oxygen deficiency). An increase in red blood cells can make the blood thicker.
  • Elevated Blood Lipids: High levels of cholesterol and triglycerides in the blood can increase blood viscosity. Elevated lipids can contribute to the development of atherosclerosis (hardening and narrowing of the arteries), which may further affect blood flow.
  • Certain Medical Conditions: Some medical conditions, such as systemic lupus erythematosus (SLE) and multiple myeloma, can affect blood viscosity and lead to thicker blood.
  • Medications: Certain medications, such as oral contraceptives, hormone replacement therapy, and anticoagulants (blood thinners), can alter blood viscosity as a side effect.
  • Hematocrit: The hematocrit is a measure of the proportion of blood that consists of red blood cells. An elevated hematocrit can make the blood thicker.
  • Dehydration: Inadequate fluid intake or excessive fluid loss (e.g., through sweating, vomiting, or diarrhea) can lead to dehydration, which can increase blood viscosity.
  • Blood Disorders: Some blood disorders, such as sickle cell disease, can affect the shape and function of red blood cells, potentially altering blood viscosity.

It’s important to note that while the term “thick blood” is sometimes used colloquially, healthcare professionals typically evaluate specific factors like hematocrit, blood lipid levels, and underlying medical conditions to diagnose and address any abnormalities in blood composition or viscosity. The treatment for thick blood or conditions contributing to it will depend on the underlying cause and may include lifestyle changes, medication management, or other medical interventions as appropriate. If you suspect you have a problem related to blood thickness or viscosity, it’s essential to consult a healthcare provider for a proper evaluation and diagnosis.