- What is the relationship between smoking and thyroid disease?
- Is it worse to smoke if you have thyroid disease? and
- Is it a coincidence that a diagnosis of hypothyroidism sometimes comes not long after quitting smoking? (For more on this, take our Thyroid/Smoking Poll!).
Back in 1996, I posted a request the Usenet thyroid newsgroup for anecdotal information from other women who, like me, were diagnosed hypothyroid after stopping smoking. I stopped smoking in July of 1995, and it was not too long after that I believe my thyroid went haywire. I began to wonder about the relationship between thyroid disease and smoking.
I received a large number of responses from women who said they'd experienced this same thing -- being diagnosed with hypothyroidims not long after stopping smoking, and were interested in more information. I contacted the Thyroid Foundation of America with these questions, and they indicated that some research had been done on the relationship between smoking and the thyroid. They sent me an article from their newsletter, The Bridge, Spring 1993, Vol. 8, No. 1, titled "Smoking and the Thyroid," by David S. Cooper, M.D., F.A.C.P. You can request a copy of this article by calling the Foundation at 1-800-832-8321.
Smoking Definitely Damages the Thyroid
The article said that tobacco smoke contains substances that affect the function of the thyroid. Studies show that smokers are more likely to have thyroid enlargement, and it is possible that mild thyroid enlargement in smokers could be a sign of subtle thyroid disturbance. According to a Jan. 27, 1993 article in the Journal of the American Medical Association smokers are twice as likely as nonsmokers to develop Graves' disease. According to that article, smoking also apparently worsens eye problems in people with Graves' disease.
Smoking Increases the Risk and Severity of Thyroid Disease
One study also suggests that that smoking may increase the risk of hypothyroidism in patients with Hashimoto's thyroiditis. [link url=http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=8957745&form=6&db=m&](Jo urnal of Endocrinology Investigation1996 Oct;19(9):607-612, "Relationship between cigarette smoking and hypothyroidism in patients with Hashimoto's thyroiditis")[/link].Also, a journal article "Cigarette Smoking and the Thyroid," The New England Journal of Medicine -- October 12, 1995 -- Volume 333, Number 15, -- says that smoking is associated with so many abnormalities of thyroid function that it is unlikely it has just one single effect on the thyroid gland.
But, the study results do not indicate that smoking causes hypothyroidism, only that it increases the severity and effects of hypothyroidism.
