‍In this article:

• What is Hashimoto's disease?

• Toxins and autoimmune disease

• Why are cigarettes harmful?

• Does smoking cigarettes increase your risk for Hashimoto's?

• Smoking cessation

Cigarette smoking correlates with numerous chronic health conditions. From heart disease and osteoporosis to lung cancer and stroke, cigarette smoking exacerbates or increases your risk for nearly every health condition. But what about autoimmune disorders like Hashimoto's thyroiditis? Ahead, an in-depth look at what the research shows between cigarette smoking and Hashimoto's risk.

What is Hashimoto's disease?

Hashimoto's is an autoimmune disorder that involves chronic inflammation of the thyroid. This autoimmune condition is the most common cause of hypothyroidism in the United States. Hashimoto's tends to run in families and most often occurs in middle-aged women. However, anyone can develop Hashimoto's at any age, including children. 

Hashimoto's is often a silent disease for many years. Thyroid inflammation goes undetected, and there are rarely any symptoms that suggest an inflammatory process is at work. With time and factors that worsen inflammation, Hashimoto's can impair thyroid hormone production in the gland, resulting in a decline in thyroid function. When the thyroid cannot produce enough thyroid hormone to support the body's metabolic needs, you can develop hypothyroidism. 

Toxins and autoimmune disease

Evidence suggests that both genetic and environmental factors can cause autoimmune diseases. However, there is still much speculation regarding how much your genes versus environmental toxins affect the presence of autoimmunity. 

We know that frequent exposure to environmental toxins can cause chronic inflammation. Furthermore, some environmental agents directly interfere with the thyroid gland by interrupting the following processes:

• Thyroid hormone synthesis

• Thyroid hormone metabolism and excretion

• The action of thyroid hormones

Toxins can also disrupt other processes related to optimal thyroid functioning, such as influencing TSH secretion from the pituitary and interrupting iodine uptake from your diet.

Why are cigarettes harmful?

Cigarette smoking is a type of environmental toxin that can cause serious health consequences. According to the American Cancer Society, 1 in 5 deaths is due to tobacco-related diseases. People who smoke regularly have a life expectancy of ten years less than nonsmokers. 

Cigarettes contain toxic substances that are damaging to your tissues. 

• Carbon monoxide is in cigarettes. It replaces oxygen in your blood, causing your organs not to receive sufficient amounts of oxygen. With low oxygen (called hypoxemia), your tissues cannot function well.

• Cigarettes may also contain tar. This sticky substance attaches to the alveoli in the lungs, making it difficult for oxygen to pass from the lungs to your blood.  

• Nicotine is the addictive substance in cigarettes that makes people hunger for more.

Along with affecting your heart, vessels, brain, lungs, GI system, skin, reproductive function, and bones, smoking also harms your immune system. Some studies suggest that smoking reduces your immune function, which causes chronic inflammation. 

Does smoking cigarettes increase your risk for Hashimoto's?

The jury is still out on what role cigarette smoking plays in Hashimoto's. Indeed, there are still many questions about the role environmental toxins play in developing Hashimoto's compared to genetic factors. 

One smaller study found that smoking cessation or continuation did not significantly impact when patients began to experience Hashimoto's symptoms before age 39. However, there was an interesting correlation found in patients who quit smoking later in life: the results suggested that stopping smoking later in life triggered Hashimoto's symptoms. Whether smoking cessation, age, or other factors like hormones (especially in menopausal women) is the primary trigger for Hashimoto's symptoms is yet to be studied.    

An older study found that people who smoked seemed to be less likely to develop TPO antibodies, present in Hashimoto's thyroiditis. However, cigarette smoking may stimulate Graves' disease, an autoimmune condition resulting in hyperthyroidism. Despite this study's results, we know that cigarette smoking is not a solution to preventing Hashimoto's, as smoking causes chronic inflammation and may also promulgate autoimmune disease. 

Smoking cessation

It is imperative to stop smoking today to ward off chronic smoking-related health conditions. Smoking can damage all of your tissues, including your thyroid gland. Smoking cessation is not easy. However, with the right action plan, you can stop. Here are some tips on how to quit smoking.

Talk to your doctor  

Your doctor may prescribe recommended medications and treatments  to help you curb smoking cravings, including: varenicline (Chantix), bupropion (Zyban), and nicotine replacement therapy (NRT).

Develop a "Quit Plan" 

Your Quit Plan is a guide created by you where you plan out your quitting strategy. It is helpful to include:

• What day you will quit

• When you will tell loved ones that you are quitting

• A list of the triggers that you will need to remove to stop reminding yourself of smoking

• Your reasons for quitting (it helps to put this somewhere that you will see every day)

• Thinking ahead about coping strategies 

• Set rewards for when you reach significant milestones

• List resources where you can get help right away if you are struggling with temptation (several helplines are available)
  

Find a support group 

If you have a friend or relative who is planning to quit smoking, try to do it together. Also, there are plenty of social support groups in person and online. 

Use supporting technology 

There are many apps, free text messages, and phone services to help you meet your goals.    

• quitSTART App — Free smartphone app with personalized tips, craving tracking, challenges, and progress tracking.
  https://smokefree.gov/tools-tips/quitstart
• SmokefreeTXT — Free text-message program providing daily encouragement, tips, and support. Text QUIT to 47848.
  https://smokefree.gov/tools-tips/text-programs/quit-for-good/smokefreetxt
• Smokefree CRAVE Text Support — Get immediate help during a craving. Text CRAVE to 47848.
  https://smokefree.gov/tools-tips/text-programs
• 1-800-QUIT-NOW — Free, confidential telephone counseling connecting you with trained quit-smoking counselors in your state. Call 1-800-784-8669.
  https://smokefree.gov/tips
• National Cancer Institute Quitline — Free telephone counseling for people who want to quit smoking. Call 1-877-44U-QUIT (1-877-448-7848)
  https://smokefree.gov/quit-smoking/getting-started/prepare-to-quit

A note from Paloma

Living with Hashimoto’s or hypothyroidism shouldn’t mean settling for rushed appointments or one-size-fits-all care. At Paloma Health, our thyroid-focused providers specialize in hypothyroidism and Hashimoto’s, offering personalized care that considers your symptoms, lab results, medical history, and individual treatment needs.

From comprehensive and convenient thyroid testing and virtual visits to medication management and ongoing support, Paloma makes it easier to get the thyroid care you need from the comfort of home. Our goal is to work with you over time—not simply prescribe medication, but help you understand your condition, monitor your progress, and develop a treatment plan tailored to you.

Frequently asked questions

Can smoking cause Hashimoto’s?

Research has not established that cigarette smoking directly causes Hashimoto’s disease. However, smoking exposes the body to toxins that can promote inflammation and affect immune and thyroid function.

Does smoking increase inflammation?

Yes, smoking can contribute to chronic inflammation and can affect the immune system. This is one reason smoking is concerning for people with autoimmune conditions such as Hashimoto’s.

Can smoking affect thyroid function?

Smoking can affect the thyroid and interfere with processes involved in normal thyroid hormone function. Cigarette smoke also contains substances that can harm tissues throughout the body.

Can quitting smoking trigger Hashimoto’s symptoms?

One small study found an association between quitting smoking later in life and the appearance of Hashimoto’s symptoms. However, researchers do not know whether quitting itself, age, hormonal changes, or other factors explain this connection.

Does smoking lower thyroid antibodies?

An older study found that smokers appeared less likely to develop TPO antibodies, which are associated with Hashimoto’s. This does not mean smoking prevents Hashimoto’s or is beneficial for thyroid health.

Can smoking increase the risk of Graves’ disease?

Some research suggests cigarette smoking may stimulate Graves’ disease, an autoimmune thyroid condition that causes hyperthyroidism. This is another reason smoking is particularly concerning for people with thyroid or autoimmune conditions.

Should I quit smoking if i have Hashimoto’s?

Yes, quitting smoking is an important step toward protecting your overall health and reducing exposure to tobacco-related toxins. Your healthcare provider can help you develop a quit plan and discuss medications or other resources that may reduce cravings.

Where can I get help quitting smoking?

Free smoking-cessation support is available through resources such as Smokefree.gov, CDC quitlines, and other evidence-based programs. You can also ask your healthcare provider about medications and strategies that can make quitting more manageable.