By Dr. Mercola
Most people realize that their thyroid is important for controlling their metabolism and body weight.
But did you know that depression, heart disease, chronic fatigue, fibromyalgia, PMS (premenstrual syndrome), menopausal symptoms, muscle and joint pains, irritable bowel syndrome, or autoimmune disease could actually indicate a problem with your thyroid?
The classic signs of a sluggish thyroid gland include weight gain, lethargy, poor quality hair and nails, hair loss, dry skin, fatigue, cold hands and feet, and constipation -- and these symptoms are relatively well known.
However, some of the conditions you might not associate with your thyroid include:
- High cholesterol
- Irregular menstruation
- Low libido
- Gum disease
- Fluid retention
- Skin conditions such as acne and exzema
- Memory problems
- Poor stamina
And there are, in fact, many more conditions that can be associated with poor thyroid function. Your thyroid plays a part in nearly every physiological process. When it is out of balance, so are you. This is why it is so important to understand how your thyroid gland works and what can cause it to run amok.
The sad fact is, half of all people with hypothyroidism are never diagnosed. And of those who are diagnosed, many are inadequately treated, resulting in partial recovery at best.
Hypothyroidism: The Hidden Epidemic
Hypothyroidism simply means you have a sluggish or underactive thyroid, which is producing less than adequate amounts of thyroid hormone.
“Subclinical” hypothyroidism means you have no obvious symptoms and only slightly abnormal lab tests. I will be discussing these tests much more as we go on since they are a source of great confusion for patients, as well as for many health practitioners.
Thyroid problems have unfortunately become quite common.
The same lifestyle factors contributing to high rates of obesity, cancer and diabetes are wreaking havoc on your thyroid… sugar, processed foods, stress, environmental toxins, and lack of exercise are heavy contributors.
More than 10 percent of the general population in the United States, and 20 percent of women over the age of 60, have subclinical hypothyroidism. But only a small percentage of these people are being treated.
Why is that?
Much of it has to do with misinterpretation and misunderstanding of lab tests, particularly TSH (thyroid stimulating hormone). Most physicians believe that if your TSH value is within the range of “normal,” your thyroid is fine. But more and more physicians are discovering that the TSH value is grossly unreliable for diagnosing hypothyroidism.
And the TSH range for “normal” keeps changing!
In an effort to improve diagnosis of thyroid disease, in 2003 the American Association of Clinical Endocrinologists (AACE) revised the “normal” TSH range as 0.3 to 3.04. The previous range was defined as 0.5 and 5.0, which red-flagged only the most glaring hypothyroidism cases.
However, the new range is still not wholly reliable as the sole indicator of a sulky thyroid gland. You simply cannot identify one TSH value that is “normal” for every person, regardless of age, health, or other factors.
Having said that though most physicians who carefully follow this condition recognize that any TSH value greater than 1.5 could be a strong indication that an underactive thyroid is present.
Your TSH value is only part of the story, and your symptoms, physical findings, genetics, lifestyle and health history are also important considerations. Only when physicians learn to treat the patient and not the lab test will they begin to make headway against thyroid disease.
Understanding How Your Thyroid Works is Step One
The thyroid gland is in the front of your neck and is part of your endocrine, or hormonal, system. It produces the master metabolism hormones that control every function in your body. Thyroid hormones interact with all your other hormones including insulin, cortisol, and sex hormones like estrogen, progesterone, and testosterone.
The fact that these hormones are all tied together and in constant communication explains why an unhappy thyroid is associated with so many widespread symptoms and diseases.
This small gland produces two major thyroid hormones: T4 and T3. About 90 percent of the hormone produced by the gland is in the form of T4, the inactive form. Your liver converts this T4 into T3, the active form, with the help of an enzyme.
Your thyroid also produces T2, yet another hormone, which currently is the least understood component of thyroid function and the subject of much ongoing study.
Thyroid hormones work in a feedback loop with your brain -- particularly your pituitary and hypothalamus -- in regulating the release of thyroid hormone. Your pituitary makes TRH (thyroid releasing hormone), and your hypothalamus makes TSH. If everything is working properly, you will make what you need and you’ll have the proper amounts of T3 and T4.
Those two hormones -- T3 and T4 -- are what control the metabolism of every cell in your body. But their delicate balance can be disrupted by nutritional imbalances, toxins, allergens, infections and stress.
If your T3 is inadequate, either by insufficient production or not converting properly from T4, your whole system suffers.
You see, T3 is critically important because it tells the nucleus of your cells to send messages to your DNA to crank up your metabolism by burning fat. That is why T3 lowers cholesterol levels, regrows hair, and helps keep you lean.
How to Know if You are Hypothyroid
Identifying hypothyroidism and its cause is tricky business. Many of the symptoms overlap with other disorders, and many are vague. Physicians often miss a thyroid problem since they rely on just a few traditional tests, so other clues to the problem go undetected.
But you can provide the missing clues!
The more vigilant you can be in assessing your own symptoms and risk factors and presenting the complete picture to your physician in an organized way, the easier it will be for your physician to help you.
Sometimes people with hypothyroidism have significant fatigue or sluggishness, especially in the morning. You may have hoarseness for no apparent reason. Often hypothyroid people are slow to warm up, even in a sauna, and don’t sweat with mild exercise. Low mood and depression are common.
Sluggish bowels and constipation are major clues, especially if you already get adequate water and fiber.
Are the upper outer third of your eyebrows thin or missing? This is sometimes an indication of low thyroid. Chronic recurrent infections are also seen because thyroid function is important for your immune system.
Another telltale sign of hypothyroidism is a low basal body temperature (BBT), less than 97.6 degrees F averaged over a minimum of 3 days. It is best to obtain a BBT thermometer to assess this.
How about your family history? Do you have close relatives with thyroid issues?
Some of the family history that suggests you could have a higher risk for hypothyroidism includes:
- High or low thyroid function
- Prematurely gray hair
- Autoimmune diseases (rheumatoid arthritis, lupus, sarcoidosis, Sjogren’s, etc.)
- Crohn’s disease or ulcerative colitis
- Multiple sclerosis (MS)
- Elevated cholesterol levels
It might be useful to take an online thyroid assessment quiz, as a way to get started. Mary Shomon has a good one. Some of the classic symptoms are mentioned above, but there are many more -- too many to list here.
If you suspect you might be hypothyroid, you should see a healthcare provider who can evaluate this, including ordering the basic lab tests for thyroid function.
Even though lab tests are not the end-all, be-all for diagnosing a thyroid problem, they are a valuable part of the overall diagnostic process. The key is to look at the whole picture.
New studies suggest a very high incidence of borderline hypothyroidism in Westerners. Many cases are subclinical, and even “sublaboratory,” not showing up at all in standard laboratory measurements.
Coexistent subclinical hypothyroidism often triggers or worsens other chronic diseases, such as the autoimmune diseases, so the thyroid should be addressed with any chronic disease.
Many physicians will order only one test -- a TSH level. This is a grossly inadequate and relatively meaningless test by itself, as well as a waste of your money. It would be like saying you know your water is pure because it tastes fine.
I recommend the following panel of laboratory tests if you want to get the best picture of what your thyroid is doing:
- TSH -- the high-sensitivity version. This is the BEST test. But beware most all of the “normal” ranges are simply dead wrong. The ideal level for TSH is between 1 and 1.5 mIU/L (milli-international units per liter)
- Free T4 and Free T3. The normal level of free T4 is between 0.9 and 1.8 ng/dl (nanograms per deciliter). T3 should be between 240 and 450 pg/dl (picograms per deciliter).
- Thyroid antibodies, including thyroid peroxidase antibodies and anti-thyroglobulin antibodies. This measure helps determine if your body is attacking your thyroid, overreacting to its own tissues (ie, autoimmune reactions). Physicians nearly always leave this test out.
- For more difficult cases TRH can be measured (thyroid releasing hormone) using the TRH stimulation test. TRH helps identify hypothyroidism that’s caused by inadequacy of the pituitary gland.
Other tests that might be indicated for more complex cases are a thyroid scan, fine-needle aspiration, and thyroid ultrasound. But these are specialized tests that your physician will use only in a small number of cases, in special situations.
Even if all your lab tests are “normal,” if you have multiple thyroid symptoms, you still could have subclinical hypothyroidism.
Keeping Your Thyroid Healthy in a Toxic World
Now that you have some understanding of the importance of your thyroid and how it works, let’s take a look at the factors that can readily cause problems with your thyroid gland.
Your lifestyle choices dictate, to a great degree, how well your thyroid will function.
If you follow my plan to eat for your nutritional type, and my nutritional plan your metabolism will be more efficient, and your thyroid will have an easier time keeping everything in check. Eating for your type will normalize your blood sugar and lipid levels and enhance your immune system, so that your thyroid will have fewer obstacles to overcome.
Eliminate junk food, processed food, artificial sweeteners, trans fats, and anything with chemical ingredients. Eat whole, unprocessed foods, and choose as many organics as possible.
Gluten and Other Food Sensitivities
Gluten and food sensitivities are among the most common causes of thyroid dysfunction because they cause inflammation.
Gluten causes autoimmune responses in many people and can be responsible for Hashimoto’s thyroiditis, a common autoimmune thyroid condition. Approximately 30 percent of the people with Hashimoto’s thyroiditis have an autoimmune reaction to gluten, and it usually goes unrecognized.
How this works is, gluten can cause your gastrointestinal system to malfunction, so foods you eat aren’t completely digested (aka Leaky Gut Syndrome). These food particles can then be absorbed into your bloodstream where your body misidentifies them as antigens -- substances that shouldn’t be there -- our body then produces antibodies against them.
These antigens are similar to molecules in your thyroid gland. So your body accidentally attacks your thyroid. This is known as an autoimmune reaction or one in which your body actually attacks itself.
Testing can be done for gluten and other food sensitivities, which involves measuring your IgG and IgA antibodies.
Another food that is bad for your thyroid is soy. Soy is NOT the health food the agricultural and food companies would have you believe.
Soy is high in isoflavones (or goitrogens), which are damaging to your thyroid gland. Thousands of studies now link soy foods to malnutrition, digestive stress, immune system weakness, cognitive decline, reproductive disorders, infertility and a host of other problems -- in addition to damaging your thyroid.
Properly fermented organic soy products such as natto, miso, and tempeh are fine -- it’s the unfermented soy products that you should stay away from.
Coconut oil is one of the best foods you can eat for your thyroid. Coconut oil is a saturated fat comprised of medium chain triglycerides (MCTs), which are known to increase metabolism and promote weight loss.
Coconut oil is very stable (shelf life of 3 to 5 years at room temperature), so your body is much less burdened with oxidative stress than it is from many other vegetable oils. And coconut oil does not interfere with T4 to T3 conversion the way other oils can.
Iodine is a key component of thyroid hormone. In fact, the names of the different forms of thyroid hormone reflect the number of iodine molecules attached -- T4 has four attached iodine molecules, and T3 has three -- showing what an important part iodine plays in thyroid biochemistry.
If you aren’t getting enough iodine in your diet (and most Americans don’t), no matter how healthy your thyroid gland is, it won’t have the raw materials to make enough thyroid hormone.
Chlorine, fluorine and bromine are also culprits in thyroid function, and since they are halides like iodine, they compete for your iodine receptors.
If you are exposed to a lot of bromine, you will not hold on to the iodine you need. Bromine is present in many places in your everyday world -- plastics, pesticides, hot tub treatments, fire retardants, some flours and bakery goods, and even some soft drinks. I have written a special article about bromine and its influence on your thyroid gland and I encourage you to read it.
Also make sure the water you drink is filtered. Fluoride is particularly damaging to your thyroid gland. Not all water filtersremove fluoride, so make sure the one you have does.
Stress and Adrenal Function
Stress is one of the worst thyroid offenders. Your thyroid function is intimately tied to your adrenal function, which is intimately affected by how you handle stress.
Many of us are under chronic stress, which results in increased adrenalin and cortisol levels, and elevated cortisol has a negative impact on thyroid function. Thyroid hormone levels drop during stress, while you actually need more thyroid hormones during stressful times.
When stress becomes chronic, the flood of stress chemicals (adrenalin and cortisol) produced by your adrenal glands interferes with thyroid hormones and can contribute to obesity, high blood pressure, high cholesterol, unstable blood sugar, and more.
A prolonged stress response can lead to adrenal exhaustion (also known as adrenal fatigue), which is often found alongside thyroid disease.
Environmental toxins place additional stress on your body. Pollutants such as petrochemicals, organochlorines, pesticides and chemical food additives negatively affect thyroid function.
One of the best destressors is exercise, which is why it is so beneficial for your thyroid.
Exercise directly stimulates your thyroid gland to secrete more thyroid hormone. Exercise also increases the sensitivity of all your tissues to thyroid hormone. It is even thought that many of the health benefits of exercise stem directly from improved thyroid function.
Even something as simple as a 30-minute walk is a great form of exercise, and all you need is a good pair of walking shoes. Don’t forget to add strength training to your exercise routine, because increasing your muscle mass helps raise your metabolic rate.
Also make sure you are getting enough sleep. Inadequate sleep contributes to stress and prevents your body from regenerating fully.
Finally, one excellent way to reduce stress is with an energy psychology tool such as the Meridian Tapping Technique (MTT). More and more people are practicing MTT and experiencing amazing results.
Treatment Options for a Sluggish Thyroid
Here are some suggestions that can be used for general support of your thyroid, as well as treating an underperforming one:
- Eat plenty of sea vegetables such as seaweed, which are rich in minerals and iodine (hijiki, wakame, arame, dulse, nori, and kombu). This is probably the most ideal form of iodine supplementation as it is also loaded with many other beneficial nutrients.
- Eat Brazil nuts, which are rich in selenium.
- Get plenty of sunlight to optimize your vitamin D levels; if you live where sunlight is limited, use vitamin D3 supplementation.
- Eat foods rich in vitamin A, such as dandelion greens, carrots, spinach, kale, Swiss chard, collard greens, and sweet potatoes.
- Make sure you are eating enough omega-3 fatty acids.
- Use pure, organic coconut oil in your cooking -- it’s great for stir fries and sautéing many different meats and vegetables.
- Filter your drinking water and your bathing water.
- Filter your air, since it is one of the ways you take in environmental pollutants.
- Use an infrared sauna to help your body combat infections and detoxify from petrochemicals, metals, PCBs, pesticides and mercury.
- Taking chlorella is another excellent detoxification aid.
- Many women suffering with hormonal imbalances report significant benefits from the South American herb maca. For more information, please review this article by thyroid expert Mary Shomon, or her Q&A session with Dr. Viana Muller on this topic.
- Take active steps to minimize your stress ... relaxation, meditation, hot soaks, EFT, whatever works for you.
- Exercise, exercise, exercise!
Thyroid Hormone Replacement
If you know your thyroid function is poor, despite making the supportive lifestyle changes already discussed, then it might be time to look at thyroid supplementation.
Taking thyroid hormone should be done only after you have ruled out other conditions that could be causing the thyroid dysfunction such as adrenal fatigue, gluten or other food allergies, hormonal imbalance, etc. It is always best to get your thyroid working again by treating the underlying cause, as opposed to taking an external source of thyroid hormone.
But sometimes supplementation is necessary.
Conventional pharmaceutical treatment usually consists of replacing only T4 in the form of Synthroid, Levoxyl, Levothyroid, Unithroid, and levothyroxine, leaving your body to convert this to T3.
However, research has shown that a combination of T4 and T3 is often more effective than T4 alone. The conversion to T3 can be hampered by nutritional deficiencies such as low selenium, inadequate omega-3 fatty acids, low zinc, chemicals from the environment, or by stress.
Oftentimes, taking T4 alone will result in only partial improvement.
Taking T3 alone is usually too stimulating. The drug Cytomel is a very short-acting form of T3 that can cause palpitations, anxiety, irritability and insomnia. I never recommend this drug.
By far, the better approach is combined T4 and T3 therapy.
Natural thyroid products, like ArmourThyroid are a combination of T4, T3 and T2 made from desiccated, or dried, porcine thyroid. Armour Thyroid has gotten a bad rap over the years, perceived by physicians to be unstable and unreliable in terms of dosage. However, many improvements have been made in the product, making it a safe and effective option for treating hypothyroidism today.
In fact, a study done ten years ago clearly demonstrated that patients with hypothyroidsim showed greater improvements in mood and brain function if they received treatment with Armour Thyroid than if they received Synthroid.
The optimal dose for Armour Thyroid ranges from 15 to 180 milligrams, depending on the individual. You will need a prescription.
Once on thyroid replacement, you will not necessarily need to take it for the rest of your life, which is a common misconception. Once all the factors that have led to your thyroid dysfunction have been corrected, you may be able to reduce or discontinue the thyroid hormone replacement.
Once on thyroid hormone replacement, I recommend you monitor your progress by paying attention to how you feel, in addition to regular lab studies.
You can also routinely check your basal body temperature. If you are on the correct dose, your BBT should be about 98.6 degrees F.
If you begin to feel symptoms such as anxiety, palpitations, diarrhea, high blood pressure, or a resting pulse of more than 80 beats per minute, your dose is likely too high as these are symptoms of hyperthyroidism, and you should let your physician know immediately.
A thyroid problem is no different than any other chronic illness -- you must address the underlying issues if you hope to correct the problem. The path to wellness may involve a variety of twists and turns before you find what works for you.
But hang in there.
If you approach it from a comprehensive, wholistic perspective, you will find in time that all of the little steps you take will ultimately result in your feeling much better than you could have ever imagined.
 Mary Shomon, “Thyroid Disease 101,” June 19, 2006
 “Major Revision of Hypothyroid Diagnosis Guidelines” March 1, 2003
 Mark Hyman M.D., The Ultra Thyroid Solution: A 7-Step Plan to Reverse Hypothyroidsim Permanently, 2008, copyright UltraWellness L.L.C. (ebook)
 Thyroid-Info, Mary Shomon, guidelines for taking BBT,
 “Nutritional Typing: Your Next Generation Key to Stupendous Lifelong Health (and Simpler Weight Management),”
 “Food Allergies—Do You Have Unexplained Symptoms?” July 13, 2007
 “’Leaky Gut’ Intestinal Protein Linked to Autoimmune Disorders” May 14, 2000
 “The Evidence Against Soy” October 7, 2008
 “More Evidence Soy is Not as Healthy as Originally Believed” August 10, 2006
 Cherie Calbom and Brian Shilhavy, “How to Help Your Thyroid With Virgin Coconut Oil” November 8, 2003
 “Hidden Toxins Disrupting Your Thyroid and Iodine Production?” September 5, 2009
 American Thyroid Association website, “Iodine Deficiency,”
 “Fluoridated Water Affects Your Thyroid Gland” December 6, 2003
 Mercola Water Filters page