High Hemoglobin Count

Causes, Symptoms, and What to Do About It

A high hemoglobin level means you have an above-normal amount of the protein in red blood cells that delivers oxygen throughout your body and brings carbon dioxide back to the lungs. When the body needs more oxygen than it is getting, hemoglobin levels rise to fix that.

High hemoglobin is often caught during routine blood tests. It may be due to lifestyle factors, like smoking or living in a high altitude, or medical conditions that promote low blood oxygen, like heart failure. Diseases that increase red blood cell production can also be to blame.

This article looks at the symptoms and causes of high hemoglobin levels, how it's diagnosed and treated, and what lifestyle changes might help keep your levels in the normal range.

An illustration with information about diet and lifestyle changes for high hemoglobin

Illustration by Laura Porter for Verywell Health

Symptoms of High Hemoglobin

High hemoglobin levels themselves usually don't cause any symptoms. Sometimes, they may cause:

  • Headaches
  • Dizziness
  • Symptoms of the underlying condition causing levels to rise (which can vary)

Complications of high hemoglobin can be serious. They include:

Causes of High Hemoglobin

Several lifestyle issues and medical conditions can cause high hemoglobin levels.

Many conditions that lead to high hemoglobin are chronic. It's possible that you may be given a diagnosis before getting an abnormal hemoglobin test result.

Lifestyle Issues

Lifestyle causes of elevated hemoglobin levels include: 

  • Smoking: Red blood cells and hemoglobin increase to compensate for high levels of carbon monoxide in cigarette smoke.
  • High altitude: Lower oxygen pressure in your environment makes your body require more hemoglobin to maintain your oxygen needs.

Sometimes, dehydration can give you false high hemoglobin results when levels are normal. This is believed to be because dehydration changes the amount of fluid in your blood. Rehydrating usually corrects the measurement. 

Medical Conditions

These conditions can make your body produce excess red blood cells, and high hemoglobin is a consequence of that: 

When to See a Healthcare Provider

While a random headache or dizzy spell probably isn't cause for concern, reach out to a healthcare provider if dizzy spells or headaches become more frequent or consistent, or are otherwise concerning.

It's also important to contact a healthcare provider if you experience any symptoms of an underlying condition that causes high hemoglobin.

Diagnosing High Hemoglobin

High hemoglobin levels show up in a blood test that's part of a routine complete blood cell count (CBC).

You'll be sent for a simple blood draw, where a healthcare professional will collect blood in a syringe and send it to a laboratory for testing.

Normal hemoglobin values vary slightly depending on the lab. Hemoglobin is usually reported in grams per deciliter (g/dL).

Assigned Sex Normal Hemoglobin
Male 13.5 to 17.5 g/dL 
Female 12.0 to 15.5 g/dL

What Can I Do If My Hemoglobin Is High?

The treatment for a high hemoglobin level depends on the cause. You may just need treatment for the underlying condition, or you may need additional treatment for the high hemoglobin.

High hemoglobin, especially in polycythemia vera, is often treated with therapeutic phlebotomy. That involves removing a unit of blood, similar to making a blood donation. This may need to be done several times.

High hemoglobin is also treated with medication to reduce the number of red blood cells, which can decrease the effects and complications of the condition.

Diet Changes

If you have high hemoglobin, it’s important that you maintain a healthy diet. No specific dietary recommendations have been established, but staying hydrated and avoiding alcohol is always beneficial.

It's also important to avoid foods that are high in sugar, which can contribute to obesity, inflammation, and other conditions that increase the risk of heart disease.

Limit your intake of foods containing trans fats, which are in many processed foods, and saturated fats. Foods containing saturated fat include:

  • Cured meats like salami
  • Sausage and bacon
  • Red meat
  • Cheese
  • Butter
  • Some baked goods

Aim to eat a healthy diet that includes:

  • An ample amount of fruits and veggies
  • Whole grains
  • Protein sources such as fish, seafood, nuts, and lean lean, unprocessed meats or poultry

Lifestyle Changes

Exercising regularly can help maintain overall health and lower your risk of developing some conditions that lead to high hemoglobin. The American Heart Association recommends aiming for at least 150 minutes of moderate exercise or 75 minutes of vigorous physical activity a week.

Getting adequate sleep is also important for optimal health. Adults ages 18 to 60 get at least seven hours of sleep a night, according to the American Academy of Sleep Medicine.

Preventing High Hemoglobin

Sometimes you can't ward off high hemoglobin. This is the case if you have a condition such as polycthemia vera, which can't be prevented.

However, there are steps you can otherwise take to prevent a rising hemoglobin count. Strategies include:

  • Not smoking or quitting if you've already started
  • Not living somewhere that has a high altitude
  • Staying hydrated

Maintaining a healthy lifestyle can help prevent some of the conditions that cause high hemoglobin, such as heart failure and kidney disease. Healthy lifestyle choices include:

  • Regularly eating fruits and veggies
  • Limiting your intake of foods that are high in sugar and trans and saturated fats
  • Not drinking alcohol
  • Exercising regularly


Elevated hemoglobin doesn’t usually cause symptoms, but it can cause complications, including blood clots. A high hemoglobin level is often an indicator of disease, including polycythemia vera, cancer, heart disease, lung disease, and kidney or liver disease.

Smoking and high altitudes can also cause hemoglobin levels to increase.

Hemoglobin levels can be checked with a routine blood test. Treatment is usually necessary for the underlying cause, and sometimes treatment is specifically needed for high hemoglobin levels as well.

Frequently Asked Questions

  • Are there any medications that can cause high hemoglobin?

    Erythropoietin is a medication that can be used to raise red blood cells if they are low. Misuse can cause high hemoglobin levels.

  • Does dehydration cause high hemoglobin?

    No, but dehydration can give you a false high hemoglobin reading on a blood test. This is because it lowers the fluid volume in your blood relative to red blood cells, which contain hemoglobin.

  • What could happen if my hemoglobin level gets too high?

    Having a high red blood cell concentration could increase your risk of blood clots. If your hemoglobin is high due to chronic illness such as cancer or kidney disease, that disease may continue to progress and cause health problems until it is treated.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Heidi Moawad, MD
Heidi Moawad is a neurologist and expert in the field of brain health and neurological disorders. Dr. Moawad regularly writes and edits health and career content for medical books and publications.