Thyroid eye disease (TED) is an inflammatory eye disorder that happens when your body mistakenly attacks the tissues around the eyes.

TED is common in people with Graves’ disease, an autoimmune condition in which the immune system attacks the thyroid gland. It’s sometimes called Graves’ orbitopathy or Graves’ ophthalmopathy.

TED can cause facial swelling, light sensitivity, dry eye, irritation, vision problems, retracted eyelids, and bulging eyes. Symptoms tend to worsen over time. In rare cases, TED can cause permanent loss of vision.

Smoking greatly increases the risk of having TED and experiencing more severe symptoms, especially if you have Graves’ disease. Quitting can lower this risk.

According to a 2021 research review, people who smoke now or have smoked in the past are at least twice as likely to develop TED than those who have never smoked.

Both first- and secondhand smoking have been found to increase the risk of TED. The more cigarettes you smoke per day, the higher your risk.

Researchers aren’t exactly sure why smoking increases the risk of Graves’ disease and TED.

One hypothesis is that smokers have a higher blood concentration of a chemical called serum thiocyanate than nonsmokers. This chemical may prevent the transport of iodide into thyroid cells. Iodide is essential for thyroid health.

Smoking may also increase congestion in the veins of the eye, reduce available oxygen to the body’s tissues, and increase inflammation in the body.

Below are seven reasons to quit smoking if you have TED.

Once a doctor diagnoses TED, treatment may include lubricating eye drops, radioactive iodine, or glucocorticoid therapy to help suppress the immune system.

Various research shows that smoking has a negative effect on treatment response.

For example, a 2010 review found that smokers undergoing radioactive iodine therapy for TED were more likely to experience an unfavorable outcome. The risk was proportional to the number of cigarettes smoked per day.

A 2003 study found that nonsmokers treated with glucocorticoid therapy were more likely to show improved eye motility (or alignment and control of eye movements) and a lower clinical activity score (CAS) than smokers after 12 months of treatment.

CAS is a scoring tool doctors use to evaluate the symptoms of TED. A score of 3 or more out of 7 suggests TED is in an active phase.

Early diagnosis of TED, along with quitting smoking, can slow the progression to a more severe form of the disease.

Severe symptoms of TED, which include vision problems and misalignment of the eyes, can have a negative impact on quality of life and can be difficult to treat.

By slowing progression, quitting can keep you from needing more aggressive treatment, like surgery.

Quitting smoking reduces the risk of developing bulging eyes (exophthalmos) and double vision (diplopia) in people with Graves’ disease.

One study from 1996 found that the risk of experiencing these two symptoms increased in proportion to the number of cigarettes smoked per day.

In addition, former smokers who quit had a much lower risk of experiencing bulging eyes and double vision than active smokers.

Along with TED, smoking increases your risk of other serious eye conditions that can cause vision loss or blindness. These include:

  • Macular degeneration: This eye disease affects central vision and can lead to vision loss if left untreated. Smokers are twice as likely to develop it than nonsmokers.
  • Cataracts: These are cloudy areas in the eye that can cause blurry vision. They can worsen over time. Cataracts require surgery and can cause blindness if not treated.

Smoking damages nearly every organ in the body. Smoking also increases your risk of developing cardiovascular disease, lung cancer, various lung diseases, and autoimmune diseases, like rheumatoid arthritis and lupus.

Many people with Graves’ disease go into remission after an initial course of treatment. But about half will experience a relapse after the initial treatment.

A 2017 meta-analysis of 54 clinical trials with a total of 7,595 participants with Graves’ disease found that smoking was strongly associated with relapse.

Most relapses occur between 6 and 18 months after stopping the treatment with antithyroid medications.

In some cases, TED may require surgery, like orbital decompression surgery, strabismus (eye muscle) surgery, or eyelid retraction surgery.

All surgeries carry risks. But the World Health Organization (WHO) found that smokers who quit about 4 weeks or more before their surgery have a lower risk of complications. They also have better outcomes 6 months later.

Quitting also reduces your risk of experiencing complications with anesthesia.

In 2020, the Food and Drug Administration (FDA) approved a new treatment for TED called Tepezza (teprotumumab).

Some insurance policies state that you must currently be nonsmoking, actively enrolled in a smoking cessation program, or at least had a discussion with your doctor about quitting before insurance will cover this drug.

People with TED who continue to smoke respond less well to treatments. Quitting has been shown to improve people’s outlooks.

A 2007 meta-analysis that included results from 15 studies on TED and smoking found that the risk of severe symptoms, like bulging eyes, declined in smokers who quit.

Study authors concluded that people with TED should be advised to stop smoking, as cessation is likely to slow or stop progression of eye disease and improve the outcome of treatment.

Smoking is the biggest risk factor associated with TED. The risk increases the more you smoke. If you have TED and smoke, quitting is considered a crucial aspect of managing the disease and supporting favorable outcomes.

Talk with your doctor about ways to quit smoking. You can also call 800-QUIT-NOW (800-784-8669) for free support.