Why is Red Cell Distribution Width (RDW) High? Causes, Symptoms, and What to Do

Red Cell Distribution Width (RDW) is a measure of the variation in size of your red blood cells. A high RDW value can indicate a variety of health conditions, so understanding its causes and implications is important. This article will help you understand what a high RDW means, why it matters, and what steps you might consider next.

What is RDW and why does it matter?

RDW stands for Red Cell Distribution Width, a blood test parameter that measures the variation in size of your red blood cells. The typical adult range for RDW is 11.5–14.5%. When RDW is higher than this range, it suggests that there is a significant variation in the size of your red blood cells. This can be a sign of various underlying conditions, such as anemia or nutritional deficiencies.

Check your own value in the calculator above

Causes of high RDW

Several factors can lead to a high RDW value:

• Anemia: Different types of anemia, such as iron-deficiency anemia or vitamin B12 deficiency anemia, can cause increased RDW. In these conditions, the body produces red blood cells of varying sizes as it attempts to compensate for the lack of essential nutrients.
• Nutritional deficiencies: Deficiencies in iron, vitamin B12, or folate can lead to a high RDW. These nutrients are crucial for producing healthy red blood cells.
• Chronic health conditions: Conditions like liver disease, kidney disease, or inflammatory disorders can also result in a high RDW.
• Recent blood loss or transfusion: If you've recently had significant blood loss or a blood transfusion, your RDW may temporarily increase as your body works to replace the lost cells.

Symptoms associated with high RDW

High RDW itself doesn't cause symptoms, but the underlying conditions might. Common symptoms related to conditions causing high RDW include:

• Fatigue or weakness
• Shortness of breath
• Pale skin
• Dizziness or lightheadedness
• Rapid heartbeat

These symptoms can vary depending on the specific condition causing the high RDW.

Frequently asked questions

What does it mean if my RDW is high?
A high RDW indicates that there is a large variation in the size of your red blood cells. This can be due to anemia, nutritional deficiencies, or other underlying health conditions.

Can a high RDW be temporary?
Yes, a high RDW can be temporary, especially if it is due to recent blood loss or a transfusion. It may return to normal as your body stabilizes.

Is a high RDW always a cause for concern?
Not always. While a high RDW can indicate a health issue, it is often evaluated alongside other tests and clinical information to determine the cause and significance.

When to see a doctor

If you receive a lab result showing a high RDW, it is important to discuss it with your healthcare provider. They can interpret the result in the context of your overall health and any symptoms you may have. Seek medical advice if you experience symptoms like persistent fatigue, shortness of breath, or any other concerning signs. It's also important to consult a doctor if you have a known condition that could affect your red blood cells.

Remember, while this information can help you understand your lab results better, decisions about your health should always be made in consultation with your healthcare provider.