Life Extension Magazine®

Woman self-checking her own thyroid health

Don't Overlook Your Thyroid

The thyroid affects every cell in your body and is a key regulator of your energy, metabolism, and body weight. Too frequently, physicians overlook a malfunctioning thyroid as a cause for fatigue, lack of concentration, and even hair loss! Eva Cwynar, MD, explains why it is essential to test your thyroid, especially as you age.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, in August 2023. Written by: LifeExtension Book Excerpt.

The Fatigue Solution by Eva Cwynar, MD, published by Hay House

Too often, uninformed physicians diagnose fatigue, difficulty concentrating, unwanted weight gain, and hair loss in their patients as the inevitable results of aging. This blanket diagnosis may be flat-out wrong.

In fact, your lack of energy and inability to focus may have nothing at all to do with your age! You may simply need to adjust a thyroid malfunction.

The thyroid affects every cell in your body and is a key regulator of your energy, metabolism, heart, and bones. In her new book, The Fatigue Solution, Eva Cwynar, MD, urges readers to have their thyroid checked with a simple blood test.

Check Your Thyroid

When was the last time you went to the doctor and he checked your thyroid? You would know if he did, because to manually examine the thyroid, you have to step behind the patient and put your hands around the patient's neck as if you were going to choke her. That's the only way you can feel for the butterfly-shaped thyroid gland, which is located at the front of the neck near the collar bone (right where a man would wear a bowtie). When I introduce this examination to my patients, I always get the same reaction: "Why are you doing that? No doctor has ever done that to me before!"

You can't breathe without the thyroid, you can't think without the thyroid, you'd constantly be constipated without a thyroid, and yet it's way down at the bottom of the list of possible causes of some very common symptoms. Are you losing your hair? It could be your thyroid. Is your voice getting hoarse and raspy? It could be your thyroid. Are you always cold? It could be your thyroid. Are you having trouble concentrating? It could be your thyroid. And if it is, it's something that is easily fixed. That's why I get so angry and excited at the same time about the subject. People are suffering needlessly, some for many years, when they could be leading much more energetic, productive lives with the right diagnosis and treatment.

The Thyroid: What, Where, and How

The Thyroid: What, Where, and How

One woman in eight will develop a thyroid disorder during her lifetime. And by the time they reach age 60, more than 20 percent of American women will have a thyroid disorder. I personally believe the numbers may be even higher because so many women haven't been officially diagnosed.

The simplest way to describe your thyroid and its function is to compare it to a furnace that is run by a thermostat (the pituitary gland). Together, they regulate how much energy and stamina you have on a daily basis. The amount of thyroid hormone you have affects how well you have slept, how you feel when you get up in the morning, and how effectively you will make it through your day.

Thyroid function affects every cell in the body. It is the main regulator of basal metabolism, which is the amount of energy needed to maintain essential physiologic functions when you are at complete rest, both physically and mentally. If your thyroid gland is not producing optimally, your cells cannot properly take in the nutrients they need, receive the right amount of oxygen, or get rid of waste materials efficiently. Thyroid hormones also affect your heart, muscles, bones, and cholesterol, to name just several of its jobs.

Introducing the 3s and 4s

There are two main hormones produced by the thyroid:

  • Triiodothyronine, known as T3
  • Tetraiodothyronine, known as T4

You may have noticed a portion of the word "iodine" in each of the hormones above. That's because the function of the thyroid gland is to take iodine, found in many foods, and convert it into thyroid hormones. Thyroid cells are the only cells in the body that can absorb iodine.

These cells combine iodine and the amino acid tyrosine to make T3 and T4.

There is one more factor we have to mention to complete this process, and that is Thyroid Stimulating Hormone (TSH), which is produced by the pituitary gland in the brain and gives that gland its thermostat-like function. So the thyroid is the furnace that provides "heat" in the form of the T3 and T4 hormones and the pituitary gland is the thermostat that goes on and off according to the amount of heat in the body. TSH tells the thyroid to raise or lower the heat.

The process goes like this:

  • T3 and T4 travel through the bloodstream, producing heat
  • The pituitary gland senses the heat; the thermostat shuts off; TSH production slows down
  • The body cools as the level of thyroid hormones decrease
  • The furnace produces more heat

When your body temperature drops, your metabolic rate drops, too. You produce less energy, and you store more calories as fat—in other words, you gain weight. You also suffer from fatigue, irritability, and the inability to concentrate.

Too Few Hormones

The most common form of thyroid disorder is hypothyroidism. Hypothyroidism occurs when the thyroid is not producing enough of its hormones. Approximately 25 million people suffer from hypothyroidism, and about half of them are undiagnosed. It is usually found in women, particularly older women; the percentage of patients with hypothyroidism is greater for women for each decade of age after age 34. That is because thyroid hormone production decreases with age.

One of the reasons that hypothyroidism often goes undiagnosed is that symptoms usually appear slowly over time, and they may appear to be signs of normal aging.

Symptoms include:

  • Anxiety and nightmares
  • Difficulty losing weight
  • Dry skin
  • Easy weight gain
  • Impaired concentration and memory
  • Menstrual irregularities
  • Mood swings
  • Severe fatigue
  • Thinning eyebrows
  • Thinning hair
  • Yellow skin from poor conversion of beta carotene to vitamin A

There are many women who have no symptoms and feel perfectly healthy, and yet, when tested, are diagnosed with hypothyroidism. These women need to be treated as well as those who have symptoms, because their slowed metabolism will result in adverse effects down the line. If you are not treated for hypothyroidism, you may have a heart attack because of the metabolic dysfunction that your thyroid has produced over the course of many years. That's the reason testing is so important, especially as you get older and the likelihood of hypothyroidism increases.

Too Few Hormones

In the United States, the most common cause of hypothyroidism is called Hashimotos's thyroiditis. This is an autoimmune disorder—in other words, the body's immune system attacks thyroid tissue. The tissue eventually becomes so inflamed that the gland can't make enough thyroid hormone. The pituitary gland, noticing the lack of these hormones, reacts by turning up the thermostat and sending out TSH to raise hormone production. But that's no longer possible because of the inflammation of the gland. Thyroid cells start to enlarge and multiply, which will eventually cause nodules and swelling. Hashimosto's disease, like many other autoimmune diseases, is most often inherited, usually from mothers to daughters.

Too Many Hormones

When everything is functioning properly, the thyroid and pituitary work together to produce just the right amount of hormones. But there are times when the thyroid malfunctions and produces either too many or too few hormones. When the thyroid becomes overactive and produces too many hormones, you end up with a condition called hyperthyroidism. This condition affects 10 times more women than men, and usually occurs in women under 40. Here are some of the symptoms of hyperthyroidism:

  • Being nervous, moody, weak, or tired
  • Excessive sweating
  • Fine hair that is falling out
  • More bowel movements than usual
  • Rapid heartbeat
  • Red, itchy skin
  • Shaky hands
  • Shortness of breath

The most common form of this disorder is Graves' disease, which was made "famous" when first lady Barbara Bush was diagnosed with the illness in 1989 (coincidentally, her husband, President George H. W. Bush, was later diagnosed with the same disease, as was their dog, Millie). One of the stranger symptoms of Graves' disease is known as "frog eyes" where the eyeballs get pushed forward and protrude because fat builds up behind them. Graves' disease can be life threatening and can lead to heart problems if left untreated. This type of hyperthyroidism is an autoimmune disease that is genetically inherited. It causes mood and body changes when the immune system "mistakenly attacks" the thyroid gland, causing overproduction of the thyroid hormones.

Too Many Hormones

People who have hyperthyroidism are often confused when they hear the diagnosis. My patients tell me, "I thought if I had hyperthyroidism, I'd be full of energy and losing weight and able to multitask like crazy! How come I'm so tired all the time?" Although this line of thinking is correct in most situations, the answer in other situations is that the overactive thyroid is burning out your body. It's affecting other organs (such as the adrenal gland) that are being compromised. It's like an engine that is constantly revving at a very high speed and going nowhere. Eventually, the parts will burn out and the engine will stop going.

Another type of hyperthyroidism is subacute thyroiditis, which involves swelling (inflammation) of the thyroid gland and is thought to be produced by a virus that usually follows an infection of the upper respiratory tract. It is often treated with anti-inflammatory drugs such as aspirin or ibuprofen to decrease both the production and the release of thyroid hormone. A beta-blocker (usually given for heart disease or hypertension or even tremor or anxiety) is also given to slow down the heart rate and make the patient more comfortable until the situation spontaneously resolves itself. This disease usually lasts for only a few months and heals itself naturally, but if left untreated can be life threatening.

Testing Your Thyroid

Testing Your Thyroid

The good news is that there is a simple blood test that can measure thyroid function to determine whether or not your hormone production is normal (the "gold standard" is to test one of many thyroid functions, which is the production of thyroid stimulating hormone). The bad news is that if you get five doctors in a room, you'll get five different opinions on what is "normal" and what is not. In my practice, I don't rely on blood tests alone because over the years I have found that what is normal for one person, and even normal for the population at large, may be abnormal for someone else. I use other tests as well (such as one that tests for particular antibodies) and palpation (examining with my hands) of the thyroid to determine its size, shape, firmness, or location to check for abnormalities. Internists may do this as well, but since they do not palpate the gland as frequently as endocrinologists do, they may miss the diagnosis. Some doctors may recommend an ultrasound of the thyroid as well.

Here's where the tricky part comes in. As of 2010, at most laboratories in the United States, the official normal reference range for the thyroid stimulating hormone blood test runs from approximately .5 to 5.0 (measured in micrograms per deciliter). Reference range is what determines—for the vast majority of physicians, who rely on blood tests almost exclusively—whether or not thyroid disease is even diagnosed at all, much less treated, and when diagnosed, how it is treated. In January of 2003, the American Association of Clinical Endocrinologists recommended that doctors "consider treatment for patients who test outside the boundaries of a narrower margin based on a target TSH level of 0.3 to 3.0." Even though many years have passed since the new range was established, some doctors use it and some don't. The issue that it raises is this: One study found that using a TSH upper normal range of 5.0, approximately 5 percent of the population is hypothyroid. However, if you use 3.0 as the top of the normal range, approximately 20 percent of the population would be hypothyroid. That means that millions of patients with hypothyroidism are being undiagnosed and untreated.

There are now more effective blood tests that provide a complete picture of how well the thyroid produces T4, how well the body converts T4 into T3, how much of the active form T3 is created, and whether there are significant anti-thyroid antibodies present. A complete panel would also include levels of free (unbound) T3 and T4. You might want to suggest to your doctor that she use the free T3 and T4, as the "regular" T3 and T4 totals may not be as accurate.

One of the problems with thyroid testing is that they are typically not on the list of things that are regularly checked in a standard or even a more comprehensive blood test panel. Just like the guidelines we have established for testing for colon cancer, for instance, beginning at age 50 and not before, it's not until you reach the age of 65 that your doctor will routinely request thyroid testing.

When you complain to your doctor about putting on weight, losing a little hair, fatigue, lack of libido—most of the time you get the same response: "Well, you are getting older, it's to be expected." If you are suffering from any of these symptoms and your doctor doesn't suggest testing, bring it up yourself. Most doctors, even though they may be skeptical, will order the testing if you insist.

I Keep Forgetting What You Said About Thyroids…

I Keep Forgetting What You Said About Thyroids…

Here is a frightening thought: many doctors have diagnosed patients with dementia and Alzheimer's disease, when in reality what they had was a thyroid disorder. A 2008 study published in the Archives of Internal Medicine found that older women who had levels of TSH that were either too high or too low had more than twice the risk of Alzheimer's disease than those with more moderate levels (the same was not true of men). This is another reason that testing your thyroid become part of your standard testing routine as you get older!

Your Numbers, Your Doctor, and You

Here's an important point to remember if do get tested and your numbers are not "normal." Hypothyroidism has a huge range, from very mild to quite severe. Not only that, one person whose TSH tests result in a reading of 2.5 may feel perfectly fine, while another person with the same reading may be suffering a battery of symptoms. The numbers and the symptoms don't always correlate. Most of the time, taking thyroid medication will cure your symptoms and you will feel better within a matter of days; by six weeks on the medication you'll have a very good idea of how it's working. Unless you tell your doctor how you're feeling, he or she has nothing to go on but your test results. You need to share with your doctor if your symptoms are getting better (or worse), and you need to be consistently retested to see how your medication is working. Your numbers may go back to normal, but if you're still not feeling well it's your responsibility to tell your doctor so that more tests can be taken or your medication can be tweaked until you find what works best for you.

It is possible, however, to go overboard with thyroid medication. Some of my patients have the "if some is good, more is better" attitude. However, too much thyroid medication can stress out the adrenal glands, which will then overproduce cortisol as well as dysregulate (impair) the ratio of cortisol and DHEA and epinephrine and norepinephrine. This will leave you more fatigued than you were in the first place, because the rest of your body's systems will not be able to produce the energy needed to keep up with your now revved-up thyroid.

Iodine Deficiency and the Thyroid

Since iodine is needed for the production of thyroid hormone, and the body does not make iodine, we have to get through what we eat. It is commonly found in foods such as saltwater fish, seaweed, sea vegetables, shellfish, bread, cheese, and iodine-containing multivitamins.

Iodized salt is now the main source of iodine in the American diet, but only about 20 percent of the salt America eats contains the micronutrient. Increasingly popular "designer" table salts, such as sea salts and Kosher salts, usually do not have much iodine. However, the majority of salt intake in the United States comes from processed foods, and food manufacturers almost always use noniodized salt in processed foods. Add to that the ubiquitous warnings against using too much salt because of our ever-pressing issues of hypertension, congestive heart disease, and other coronary artery diseases, and iodine deficiency becomes a real threat for some people in the United States. Whereas, just a few years ago iodine was mandated by the FDA to be included in salts (and was for decades), now most medical advice states that, due to the large variety of food sources available from all over the world, iodine in salt is no longer necessary in the United States and other Western countries. Iodization of salt is now voluntary in America. It appears that iodine intake has declined by 50 percent in North America in the past 30 to 40 years and the anticipated rate of future hypothyroid cases has risen dramatically.

Before the 1920s, iodine deficiency was common in the Great Lakes, Appalachian, and Northwestern regions of the United States and Canada; however, the introduction of iodized salt has virtually eliminated the problem in those areas. Iodine deficiency can lead to goiter, hypothyroidism, and even to mental retardation in infants and children (the term "cretin" comes from the fetus not getting enough iodine while in the mother's womb).

Worldwide, the number one cause of hypothyroidism is iodine deficiency, which remains a public health problem in 47 countries, and about 2.2 billion people (38 percent of the world's population) live in areas with iodine deficiency. An article in The Lancet in 2008 stated that, "According to WHO, in 2007, nearly 2 billion individuals had insufficient iodine intake, a third being of school age. Thus iodine deficiency, as the single greatest preventable cause of mental retardation, is an important public health problem."

There are many different types and brands of iodine supplementation available over the counter. It's important, however, that you get guidance from your doctor or health professional before taking any iodine supplementation. If you take too much, you can develop hyperthyroidism.


Thyroid Treatments

Thyroid Treatments

One of the first thyroid treatments that was commercially available was Armour Thyroid, which was a natural product made of desiccated pig and cow thyroid glands put into pill form. It is still available today. It contains both T3 and T4 hormones. It fell out of favor over the years because quality control of this medication was difficult. In recent years, however, production has become much more stable and it is back in use again. Your doctor may prescribe Armour Thyroid if you have had problems with a synthetic therapy, or if you or your doctor prefer natural products.

The most commonly prescribed synthetic drug for hypothyroidism is called levothyroxine, known under the brand names Synthroid, Levothroid, Levoxyl, and Unithroid. A more recent addition is a drug called Tirosint, which is made in Switzerland and distributed in the United States. It has fewer additives and preservatives than the other synthetic medications, so it may be a good choice for you if you find you're allergic to any of the other brands.

Another popular drug is called Cytomel, which contains only T3. Synthroid contains only T4, which must be converted to T3 by the body. Some people respond better to T3 preparations because they have trouble converting T4 into T3; those people fare better with either a combination of T3/T4 or T3 alone.

The mineral selenium decreases the antibodies that form in Hashimoto's thyroiditis, thereby decreasing the inflammation, which is why I recommend selenium to everyone who has hypothyroidism. It is also useful as a messenger in the brain helping with the communication between the thyroid and the adrenal gland.

How to Take Thyroid Medication

Although thyroid problems are usually easily treated with medication, it can be tricky to take because of how thyroid hormones react with other substances. Tell your doctor about all the prescription and over-the-counter medications you use because there are many other medicines that can affect thyroid medications. This includes vitamins, minerals, and herbal products. There are also some substances that block the absorption of thyroid medications (e.g., soy, calcium, iron, some mood altering prescription medications), which is why some patients don't see the results they'd like.

How to Take Thyroid Medication
  • Do not take thyroid medication within two hours of eating as food may delay or reduce its absorption.
  • Do not take estrogen, birth control pills, or hormone replacement therapy in the pill form at the same time you're taking thyroid medication (you can take them in the same day, just not at the same time of the day). Any form of oral estrogen may be a problem if taken at the same time as thyroid because both estrogen and thyroid hormone share the same binding globulin (a protein to which thyroid hormone binds in the blood and from which it is released into tissue cells) in the liver. If you take them both at the same time, you're not absorbing as much of either one. This does not apply if you are taking other forms of birth control, such as the patch or the NuvaRing; transdermal (through the skin) hormone replacement; or sublingual (dissolving directly into the bloodstream from drops or lozenges into the mouth) hormone replacement. That's another reason why I treat my menopausal women who have hypothyroidism with a hormone CREAM instead of the standard oral prescription pill.
  • Calcium also prevents absorption of thyroid medication, so they should not be taken at the same time.
  • Iron, whether alone, or as part of a multivitamin or prenatal vitamin supplement, interferes with thyroid hormone absorption. You should not take your iron supplements or your vitamins with iron at the same time as your thyroid hormone, and should allow at least two hours (four being the optimal time frame) between taking them.

Your Thyroid and Menopause

Although it is very rarely mentioned, your thyroid and your reproductive cycle are closely related. Thyroid problems can cause irregularities in the menstrual cycle, and even infertility in extreme cases. As you get older, these problems can become exacerbated. In fact, untreated hypothyroidism can cause a woman to be in an artificial premature perimenapause or even throw her into menopause.

It's important to remember that the thyroid is part of the overall endocrine system, and when any of this system's hormones get out of balance, all of the parts suffer. So when you go through times where hormonal imbalance is more than likely—such as pregnancy, perimenopause, and menopause—your thyroid is also more than likely to get out of whack as well.

Your Thyroid and Menopause

That is why women over 50 should be tested for thyroid problems every few years (earlier if you have a family history) and woman over 65 should be tested annually. Any woman of any age should be tested at any time and as frequently as needed if she has symptoms of hypothyroidism. Your doctor will then be able to determine whether you need thyroid hormone medication, and/or iodine or other supplementation.

In dealing with thyroid problems, it's important to find a doctor who will listen to your symptoms and be open to the newest research, the latest reference range recommendations, inclusive testing, and who understands that each patient will react differently to various treatments. You may need to see an endocrinologist, someone who is trained in the art and science of working with hormones, to get the results you need and deserve.

It makes me frustrated to know that there are so many women who suffer unnecessarily for so many years. I hear it over and over again, how finally being diagnosed and treated for thyroid problems has changed women's lives. They have accepted their "lot in life" for so long that they have almost forgotten what it's like to have energy and focus and fun in their lives. I'm here to tell you, don't just accept it. Get tested. Check your results. Ask for a copy of your labs. See a specialist. Don't settle—if you don't agree with your doctor, go somewhere else. You know your body better than anyone else. Listen to it and get your life and your health back in your hands.

The "Check Your Thyroid" Jump Start Tip

Taking Matters into Your Own Hands—or Armpits. If you suspect you're having thyroid problems and you want to check yourself out at home, there is a simple test you can do called the basal temperature test. Here are the steps:

  • Get a basal thermometer (the kind you can use under your tongue). Leave it overnight on your bedside table.
  • First thing in the morning, before you get out of bed, tuck the thermometer under your armpit and lay completely still for 10 minutes. Set a timer before you begin so that you don't have to move around to look at the clock.
  • Record your temperature for there to five days. If your temperature is consistently below 97.8°F, you may have a thyroid problem, and you should have yourself evaluated by a health professional.

Remember, thyroid disease is not just about fatigue, it can ultimately affect your morbidity as well as your mortality. Take control, but do it with the assistance of an expert.

Excerpted with permission from The Fatigue Solution by Eva Cwynar, MD, published by Hay House. For more information on Dr. Eva Cwynar, visit

Editor's Note

Science continues to evolve, and new research is published daily. As such, we have a more recent article on this topic: Do You Suffer From Suboptimal Thyroid Function?