Could You Have an Underactive Thyroid?

Could You Have an Underactive Thyroid?Do you feel tired much of the time? Gaining weight? Tend to have cold hands and feet? And… are a middle-age woman?


If you answered “yes” to most of these questions, there’s a chance you’re suffering from low thyroid gland activity, also known as hypothyroidism. Other common signs are hair loss, dry skin, depression, and reduced sex drive. Hashimoto’s thyroiditis, an autoimmune disease, is the most common cause of hypothyroidism.


The thyroid is the regulator of your metabolism – that is, how efficiently you burn food for energy and maintain your body temperature. This butterfly-shaped gland, located in the neck, secretes several hormones, of which T3 (triiodothyronine) and T4 (thyroxine) are the most important.


Both men and women can experience low thyroid activity, but perimenopausal women seem to be at a particularly high risk. That’s because they often have overlapping hormone-related issues – low estrogen and insulin resistance – creating a complex situation that many doctors don’t have the time to investigate. Even well-meaning physicians can fail to identify hypothyroidism because they either don’t order the correct tests or they don’t correctly interpret the results.


Thyroid Hormone Primer

Hormones always interact with and affect other hormones. Your pituitary gland releases thyroid-stimulating hormone (TSH) to begin and maintain production of thyroid hormones. The thyroid makes T4 first, and then, through a family of highly specialized enzymes, T4 gets converted to T3.


It all sounds simple enough, but things can go wrong – and go unnoticed. Infections, injuries, prediabetes, type-2 diabetes, chronic inflammation, alcohol and drug abuse, surgery, and the aging process itself can impact thyroid activity, according to Ron Hunninghake, M.D., a nutritionally oriented physician in Wichita, Kansas.


Most physicians will measure TSH levels to determine thyroid function. If TSH levels are elevated, it’s a clear sign of low thyroid activity. In effect, the pituitary gland keeps sending out more signals to make thyroid hormones. However, a normal TSH won’t reveal more subtle signs of low thyroid, sometimes referred to as subclinical hypothyroidism.


Doctors will also commonly measure a patient’s T4 levels. However, T4 is relatively inactive as a thyroid hormone. The body must convert it to T3, which is the most biologically active thyroid hormone.


If you suspect some form of low thyroid activity, you can perform the basal temperature test at home. You’ll need to use an old-fashioned oral glass thermometer (non-mercury types are still sold at drug stores). When you go to bed, shake it down and keep it within easy reach. As soon as you wake up in the morning, while moving as little as possible, slip the thermometer in the fold of your armpit and leave it there for 10 minutes. Write down the temperature, and do this for three to five days in a row. If you’re a woman, don’t do this test during your menstrual period or when you’re ovulating because your body temperature will be higher at these times.


Add all of the basal temperatures, and then divide by the number of days to obtain an average. Normal basal temperatures range from 97.8 to 98.2 degrees. If your average temperature is 97.7 degrees or less, you are probably hypothyroid. If that’s the case, ask your doctor to run additional tests to confirm and pinpoint the specific problem.


The key at this point is to assert yourself and ask your doctor for a full thyroid “panel,” specifically to test for free T4, free T3, and TSH. (Free T4 and free T3 are unbound hormones.) Request a copy of the report from your doctor’s office. This report will list your levels plus the range of normal levels. Low or low-normal T3, T4, or both, is a definite sign of low thyroid. But this is what’s often missed: If your T4 is normal, but your T3 is either low or low-normal, your body is not efficiently converting T4 to T3.


One other bit of advice: When you ask your doctor to order a thyroid panel, ask him or her to add a test for “reverse T3.” This test is especially important if you have been under a lot of stress. That’s because high levels of stress hormones interfere with the conversion of T4 to T3 and instead boost production of reverse T3. Reverse T3 does not function as a real thyroid hormone. Instead, it inhibits the activity of T3.


Nutritional Supplements That Support a Healthy Thyroid

Three nutrients have the greatest bearing on your thyroid hormone levels: L-tyrosine, iodine, and selenium. You need adequate amounts of these three nutrients to make and use thyroid hormones.


L-tyrosine. This amino acid (protein building block) forms part of the chemical foundation of your thyroid hormones. It’s also a building block of the body’s stimulating  neurotransmitters, including adrenaline and dopamine. Consider taking 500 mg of L-tyrosine immediately on waking, about 10 to 15 minutes before consuming any food or liquid other than water. You can take larger amounts if your naturopathic or nutritionally oriented physician thinks they would be helpful. Caution: If you have hypertension, monitor your high blood pressure after taking L-tyrosine because it may increase blood pressure. Stop taking L-tyrosine if you develop an unsafe increase in blood pressure.


Iodine. This essential dietary mineral also forms part of the foundation of your thyroid hormones. T4 contains four iodine atoms, and T3 contains three iodine atoms. Multivitamins and kelp supplements do not contain enough iodine to help normalize your thyroid function. You may need to take up to 5,000 mcg of iodine for a couple of months before reducing the amount.


Selenium. You need selenium to make the enzymes that convert T4 to T3. A two-year study conducted at the U.S. Department of Agriculture’s research center in Grand Forks, North Dakota, found that taking 200 mcg of supplemental selenium significantly increased T3 levels in men and slightly increased its levels in women.[i] Meanwhile, a European study reported that 200 mcg of selenium daily effectively reduced antibodies and improved mood and well being in people with Hashimoto’s thyroiditis.[ii] As a general rule, 200 mcg of selenium – an amount found in most multivitamins – is sufficient to improve thyroid function. You can increase your selenium intake to 400 mcg daily, but do not go above this amount without specific guidance from your physician.


Vitamin D. A study by researchers in Istanbul, Turkey, found that vitamin D deficiency was present in 92 percent of patients with Hashimoto’s thyroiditis. By comparison, vitamin D deficiency was identified in only 63 percent of people without the disease. Try taking 5,000 IU daily of vitamin D.[iii]


Multivitamin/multimineral. Other important nutrients in thyroid activity include vitamins B6 and B12, and the minerals zinc, chromium, and iron. You can obtain adequate amounts of these nutrients in a quality multivitamin/multimineral supplement.


Glandular supplements. Glandular supplements contain thyroid tissue that has been frozen and then dehydrated before being encapsulated. Some glandular supplements are obtained from range-fed animals. These products are best taken under the guidance of a physician, but they are available without a prescription.


Natural Medications for Low Thyroid

If nutritional supplements fail to improve your thyroid activity, you may have to opt for a prescription drug. Although doctors tend to prescribe synthetic T4, natural porcine-source thyroid medications are available. For example, if you are not efficiently converting T4 to T3, adding T4 won’t help improve thyroid function.


If you have to use prescription thyroid extract, insist on a prescription for natural thyroid hormone, which is sold under the names Amour Thyroid, Nature-Throid, and Westhroid. These products contain both T4 and T3. Yet another option is synthetic version of T3, prescribed as Cytomel. Many doctors are reluctant to prescribe natural thyroid hormone because they are not familiar with its dosing, which is different from synthetic versions of the hormone. If your doctor seems unsure, ask him or her to visit, where the conversions are clearly spelled out.


If you take thyroid medications, avoid aluminum- or magnesium-containing antacids and magnesium supplements (or supplements that contain magnesium, such as a cal-mag supplement), or use them 12 hours after you take any thyroid medications.


Foods that Influence Thyroid Activity

In addition to supplements, there are certain foods that support healthy thyroid activity. They include seafood and seaweed, which are rich in iodine. Brazil nuts are the richest food source of selenium. You’ll find L-tyrosine in all whole proteins, including fish, chicken, turkey, and eggs. Other foods contain goitrogens, substances that interfere with normal thyroid activity. Cooking generally inactivates goitrogens. However, if your thyroid activity is significantly low, it may be best to completely avoid these foods, at least for several months. The foods include cruciferous vegetables (e.g., broccoli, Brussels sprouts, cabbage, cauliflower, kale, kohlrabi, mustard greens), soy, radishes, rutabaga, spinach, turnips, pine nuts, peanuts, and millet.


One final note. If you suspect that you might be suffering from adrenal exhaustion – if you feel very stressed and perpetually tired, or if you consume large amounts of caffeine – focus first on supporting your adrenal function before addressing potential thyroid issues. Otherwise, you risk further stressing your adrenal glands and exacerbating your adrenal exhaustion. You can read more about adrenal exhaustion at


The Low Thyroid Quiz*


Take this quiz to determine your risk of hypothyroidism. The more signs you check, the greater your risk. Please consult with your physician if you are at high risk.


The top five signs of low thyroid activity are:

__ Fatigue

__ Headaches

__ Cold hands/feet

__ Constipation

__ Depression (unexplained)


The other signs of low thyroid activity are:

__ Acid indigestion

__ Acne

__ Allergies

__ Anxiety

__ Arthritis/achy joints

__ Asthma

__ Bad breath

__ Blood pressure (low)

__ Bruising

__ Caffeine use (increased)

__ Carpal tunnel syndrome

__ Cholesterol (elevated)

__ Cold intolerance

__ Colds and sore throats (frequent)

__ Constipation

__ Concentration (poor)

__ Coordination (poor)

__ Eyebrows (loss or thinning)

__ Eyes (dry or blurred vision)

__ Falling asleep during the day

__ Exhaustion

__ Fluid retention (edema)

__ Flushing of skin

__ Gastric reflux

__ Hair (dry, loss, or prematurely gray)

__ Hives

__ Hypoglycemia

__ Infertility

__ Insomnia

__ Irritability

__ Irritable bowel syndrome

__ Itchiness

__ Lightheaded feeling

__ Low motivation

__ Memory – poor

__ Menstrual cramps

__ Menstrual periods (irregular)

__ Migraines

__ Muscular aches

__ Nails (unhealthy looking)

__ Panic attacks

__ Premenstrual syndrome

__ Ringing in the ears

__ Self-esteem (low)

__ Sexual development inhibited

__ Sex drive reduced

__ Skin (dry)

__ Skin infections (increased)

__ Skin pigmentation (changes)

__ Sweating (lack of)

__ Throat (abnormal swallowing sensations)

__ Tired after eating

__ Tobacco use (increased)

__ Ulcers

__ Urinary infections (frequent)

__ Weight gain (unexplained)

__ Wound healing (slow)

__ Yeast infections (frequent)


*Reprinted with permission from No More Fatigue, by Jack Challem (Wiley, 2011)

[i] Combs GF, Midthune DN, Patterson KY, et al. Effects of selenomethionine supplementation on selenium status and thyroid hormone concentrations in healthy adults. American Journal of Clinical Nutrition, 2009;89:1808-1814.

[ii] Toulis KA, Anastasilakis AD, Tzellos TG, et al. Selenium supplementation in the treatment of Hashimoto’sthyroiditis: a systematic review and meta-analysis. Thyroid, 2010; doi 10.1089/thy.2009.0351.

[iii] Tamer G, Arik S, Tamer I, et al. Relative vitamin D insufficiency in Hashimoto's thyroiditis. Thyroid, 2011;21:891-896.


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03/13/2013 - 1:18pm

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