Why Is Good Oxygen Saturation of the Blood So Important?

When you go to your doctor, they may measure your blood oxygen saturation. Oxygen saturation of the blood is likely something you have heard of, but you may not know what it means.

As you might guess, having enough oxygen in your blood is vital. However, why is good oxygen saturation of the blood so important? This article discusses blood oxygen saturation, why it’s essential, and other relevant aspects.

What Is Oxygen Saturation of the Blood?

Blood oxygen saturation may also be known as your blood oxygen level—how much oxygen you have circulating in your blood. Oxygen is essential to survival, as our bodies need it to function.

When you inhale air, you take in oxygen, which passes into your bloodstream. Once oxygen enters your bloodstream, it is transferred to all the cells in your body that need oxygen to function and create energy.

Your body needs oxygen to think, move, exercise, digest your food, etc. Once your cells have used the oxygen, carbon dioxide is created, which your bloodstream then carries back to your lungs for you to breathe out.

Your blood oxygen level indicates how well your body absorbs and uses the oxygen you breathe in. Normal blood oxygen levels mean you are in good health, barring other conditions.

However, a low blood oxygen saturation level is an indication that you may be suffering from a serious health condition or may be an indication that you are developing a serious illness.

If you don’t have enough oxygen in your blood, none of the cells or organs in your body can function correctly.

What Is a Normal or Good Blood Oxygen Saturation Level?

Before talking about normal blood oxygen saturation levels, consider that different laboratories have different ranges for what they find acceptable.

However, generally speaking, between 95% and 100% is considered normal or good blood oxygen levels.

A saturation level between 90% and 95% is also considered relatively good. However, blood oxygen levels below 90% indicate you do not have enough oxygen in your blood.

Low Blood Oxygen Levels – Hypoxemia

A blood oxygen saturation level below 90% is considered very low and means you are suffering from hypoxemia.

General hypoxemia may cause relatively mild issues such as headaches, shortness of breath, and dizziness. However, it can also affect brain and heart function in more severe cases. When hypoxemia causes low oxygen levels in your body tissues, it is known as hypoxia.

Symptoms of Hypoxemia

Suppose you have hypoxemia or low blood oxygen levels. In that case, you may experience various symptoms such as shortness of breath, headache, coughing, a fast heartbeat, confusion, wheezing, bluish color of the lips, fingernails, or skin.

If you experience one or more of these symptoms, you are likely suffering from hypoxemia or low blood oxygen saturation, and you should get tested for blood oxygen saturation.

Why Is Good Oxygen Saturation of the Blood So Important

What Causes Hypoxemia or Low Blood Oxygen Levels?

Various conditions may cause low blood oxygen levels.

One of the most common causes of hypoxemia is various lung conditions. These can include bronchitis, emphysema, and asthma. Also, different heart conditions, such as heart defects, may cause low blood oxygen levels.

Another leading cause of low blood oxygen levels is sleep apnea when you do not breathe properly during your sleep. Other issues such as scarring of the lung tissue or inflammation of the lung tissue may also cause low blood oxygen levels.

Mountain climbers may also experience hypoxemia due to the high altitude, simply because there is less oxygen at high altitudes.

Perhaps one of the biggest leading causes of low blood oxygen levels is smoking, which damages the lungs, and you’re not able to take diffuse as much oxygen through the lung tissue and into the bloodstream.

How Are Blood Oxygen Levels Tested?

When you go to your doctor for low blood oxygen levels, they will do a physical exam. First, they will listen to your lungs and heart to see if everything sounds normal. They might also check to see if your skin, fingernails, or lips look bluish. However, there are then two tests that are used to diagnose low blood oxygen levels.

The first test is known as pulse oximetry. This is performed with a small device known as a pulse oximeter, a small electronic device that generally clips over your fingertip.

This device shines infrared light into your skin and into your capillary blood. The pulse oximeter measures how much light is reflected off of the hemoglobin in your blood. In simplest terms, it’s like sonar to measure your blood oxygen levels.

The second way blood oxygen levels are measured is by drawing blood. This is known as an arterial blood gas test. A machine analyzes the blood to determine blood oxygen saturation levels.

How to Increase Blood Oxygen Levels and Treat Hypoxemia

Various things can be done to treat hypoxemia, including treatments or medications to treat the underlying condition. Oxygen therapy is the first choice to elevate a low blood oxygen saturation level.

You may also be given inhalers or medications to help your lungs absorb more oxygen. Furthermore, you can do things to help increase blood oxygen levels.

  • Take deep and slow breaths
  • Drink ideal amounts of water
  • Cough very hard several times
  • Sit up straight or stand up
  • Be active and increase your overall cardiovascular health
  • Practice breathing exercises
  • Stop smoking


An adequate blood oxygen saturation is vital for your body to function. If you have a pulse oximeter and it measures below 88%, seek immediate medical attention.