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What is FEV1? Here’s What You Need to Know

15 Jun 2016
| Under Disease Education, Medical | Posted by | 13 Comments
What is FEV1? Here's What You Need to Know

What is FEV1? It is a critical measurement for those with lung disease. Find out why.

People who have a lung disease like chronic obstructive pulmonary disease (COPD), pulmonary fibrosis or emphysema know that FEV1 is an important factor in measuring their respiratory health. However, not everyone knows why. Although FEV1 is the standard unit of measurement used by doctors, governments and insurance agencies to determine coverage, to a patient, it can feel like just another number.

With your health in mind, the Lung Institute is here to break down what this metric means for your respiratory health and diagnosis moving forward. So what is FEV1? Here’s What You Need to Know.

What is FEV1?

To put it simply, FEV1 is the maximum amount of air you can forcefully blow out of your lungs in one second and is measured using a spirometer, an instrument that measures pulmonary air flow by having a person blow into a plastic tube. It is used to show lung capacity and helps pulmonologists classify COPD patients into stages. The lower the FEV1, the more severe the disease. However, the FEV1 is not used to diagnose COPD, rather, to determine the severity of it. Instead, forced vital capacity (FVC) is used to diagnose COPD, but more on that later.

What is FEV1? Here’s What You Need to Know

What Does It Mean?

The results of the FEV1 are particularly useful when compared with current standards or expected values based on a healthy person, along with gender, height and race. By comparing your FEV1 with the general standard, a doctor can determine the stage of your COPD—that is, how far it has progressed.

In practice:

  • An FEV1 of 80> of the expected value indicates mild COPD.
  • An FEV1 between 50-80 percent indicates moderate COPD.
  • An FEV1 between 30-50 percent indicates severe COPD.
  • An FEV1 of <30 percent indicates very severe COPD.

The Relationship between FVC and FEV1

As you might guess, FVC and FEV1 are closely related. Your FEV1 is divided into your FVC, and the resulting percentage determines whether you have COPD. It’s important to keep track of your FEV1 after diagnosis because it is used to determine the progression of your COPD, as well as the decline of your lung function. Staying on top of your FEV1 is critical to managing your COPD, so test yourself if you notice changes in your lung function.

We hope that you’ve found What is FEV1? Here’s What You Need to Know helpful. As millions across the U.S. continue to see the quality of their lives decline, it may be time for intervention-oriented treatments such as cellular therapy. However, time can be a factor in any decision. If you’re looking to take control of your health, don’t wait. If you or a loved one suffers from COPD or another lung disease, the Lung Institute may be able to help with a variety of cellular therapy options. Contact us at (800) 729-3065 today to find out if you qualify for cellular therapy.

Still have questions regarding What is FEV1? Here’s What You Need to Know? Share your thoughts and comments below.


  1. PB

    1 year ago

    Dear Kimmy,

    First and foremost, we’re sorry to hear that you’ve been going through such a difficult time with COPD. Like you, many people with COPD have trouble maintaining a healthy weight. We understand how challenging it can be to quit smoking, but it’s very important for your lung health and overall health to be smoke-free. For our free smoking cessation guide, click here.

    It’s understandable to feel depressed and frustrated, and many people living with chronic conditions experience these tough emotions. One way to receive help is to see a local mental health counselor. They can teach you ways to cope, techniques for relaxation and be an objective, helpful listening ear. You can also talk with your doctor or ask someone at your local hospital about COPD support groups in your area. Having the support and guidance of others dealing with similar challenges can be very helpful.

    We hope this information is helpful for you, and we wish you the best.

    Kind Regards,

    The Lung Institute

  2. kimmy smith

    1 year ago

    Hi,I have copd since I was 45 years old,and now I’m 59,I been in denial since they said I had copd,I also have weight problem underweight,and major depressed,I take 17 medication a day,still in denial!!!I have been told bad news from a specialist that I need a lung trasplant,I don’t feel like I do,once again denial,transplant center wouldn’t consider me due to weight and yes I’m trying to quit smoking,but I’m not really healthy to go for surgery. My question is how to realize what is going on with me so I can take charge of what life i have left,just can’t seem to do that. I’m in late stage of copd

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  10. Cameron Kennerly

    2 years ago

    Hello Rob,

    That’s excellent news! We’re happy to hear that your health and quality of life have improved since treatment. Please feel free to keep us updated on your progress.


    -The Lung Institute

  11. Rob Stewat

    2 years ago

    Six months after having my first cell therapy for Sarcoidosis, which is restrictive versus obstructive. My FEV1 did not change much, but my diffusion rate increased 26%. I assume this means that my lung volume is still the same but my lungs are doing a better job of processing the oxygen that I am taking in. I know that my shortness of breath has went away and my O2 numbers are now in the upper 90’s instead of lower or mid 90’s. I had a booster in April and hope to see continuing success.

  12. PB

    2 years ago

    Dear Wanda,

    First and foremost, we’re sorry to hear that you and your family have been going through such a difficult time. Many patients have found treatment fundraising helpful. If you’re interested in reading more about treatment fundraising tips, click here. We’re happy to answer any questions you have about cellular treatment options, candidacy and cost, so feel free to contact us at (855) 313-1149 to speak one-on-one with a patient coordinator. We look forward to hearing from you soon.

    Kind Regards,

    The Lung Institute

  13. wanda smith

    2 years ago

    I have stage 4 copd. I am healthy in other ways. I really want to live plus I have two daughters with breast cancer .One was a 10 year survivor and now it is metastatic breast cancer of the bones. I wish I could get funds to do this. One of my daughters is mentally retarded and their father passed away of cancer.

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