Low Thyroid (Even if Tests Are Normal) Is a Major Cause of Heart Attacks

Published: October 22, 2012

In earlier newsletters, we talked about how missing an underactive thyroid by relying on blood testing is a major cause of totally preventable miscarriages (over 50,000 a year in the US alone). It is also a major cause of unexplained infertility (see "Addressing Infertility Naturally"), unexplained fatigue, fibromyalgia, chronic pain, and a host of other problems. A new landmark study showed that women whose thyroid blood tests showed thyroid function to be in the lower third of the normal range vs. the upper third (i.e., TSH was in the upper third vs. the lower third) of the normal range (which doctors would say is "just fine") were 69% more likely to die from a heart attack. As heart attack is the most common cause of death in the US, a 69% decrease in risk is massive. To put this in perspective, cholesterol lowering medications only decreased heart attacks by 1.4% in those without underlying heart disease (review of cholesterol medication research). This makes thyroid, which is dirt cheap and makes you feel better, about 50 times more effective than Mevacor family medications (which cost billions of dollars a year and are fairly toxic in many cases). If you are tired, achy, have weight gain or are cold intolerant, ask your holistic doctor about a trial of natural Armour Thyroid. Besides helping you feel a lot better, it could save your life!

In this study, Åsvold and colleagues prospectively studied the association between TSH levels and fatal heart attacks in participants of the Norwegian Nord-Trøndelag Health Study (HUNT) study. 17,311 women and 8,002 men without known thyroid, cardiovascular disease, or diabetes mellitus at baseline were followed fr an average of 8.3 years, and 228 women and 182 men died of heart attacks. Of these, 192 women and 164 men had TSH levels within the normal clinical reference range of 0.50 to 3.5 mIU/L. Interestingly, these researchers recognized over 10 years ago that a TSH over 3.5 represents an underactive thyroid. Most American labs are still horribly outdated in the science they use, and consider a TSH up to 5.5 to be "normal."

The study showed that women with intermediate (1.14-2.52) or "high" levels (2.5-3.5) of TSH had a 41% and 69% increased risk of heart attack death compared with women who had TSH levels in the lower range of normal (0.50-1.4 mIU/L). Women whose thyroid levels were actually abnormally low had an even greater risk of heart attack.

Cardiovascular disease kills 2,800 Americans every day. Much of this is preventable using natural therapies. If thyroid medication was patentable and expensive, the drug companies would spend hundreds of millions of dollars to be sure doctors knew the research and used thyroid therapies more often. Because it is cheap though, I suspect hundreds of thousands (if not millions) of Americans will die unnecessarily because of ignorance about the importance of addressing hypothyroidism. The good news is that with health care reform on the national agenda, we have the possibility at hand to heal our health care system.

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Åsvold BO, Bjoro T, Nilsen TIL, et al. Thyrotropin levels and risk of fatal coronary heart disease. The HUNT study. Arch Intern Med. 2008;168:855-860.

Jacob Teitelbaum, MD

is one of the world's leading integrative medical authorities on fibromyalgia and chronic fatigue. He is the lead author of eight research studies on their effective treatments, and has published numerous health & wellness books, including the bestseller on fibromyalgia From Fatigued to Fantastic! and The Fatigue and Fibromyalgia Solution. His newest book (June 10, 2024) is You Can Heal From Long COVID. Dr. Teitelbaum is one of the most frequently quoted fibromyalgia experts in the world and appears often as a guest on news and talk shows nationwide including Good Morning America, The Dr. Oz Show, Oprah & Friends, CNN, and Fox News Health.

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