Thyroid hormone medications are the second top-selling category of drugs in the U.S. today. Over 23 percent of Americans are currently being treated for low thyroid (hypothyroid). And it is estimated that an additional 30 percent have yet to be diagnosed.
The thyroid gland, located at the front of your throat, receives and sends hormonal messages that travel through your bloodstream and affect the rate that food is metabolized for energy. The thyroid determines how quickly your heart beats, and your ability to lose weight or maintain a healthy weight. Those persons with low thyroid may also notice that hair is thinning, including the eyebrows; your skin will wrinkle excessively and be dry; your sex drive will be gone; and you may experience menstrual problems or severe menopause symptoms.
Know Your Thyroid Hormones
Thyroid stimulating hormone (TSH) is secreted by the pituitary. TSH stimulates the production of thyroid hormones and the growth of thyroid cells.
Thyroxin (T4) is the most abundant thyroid hormone. It is made from tyrosine and iodine. Triiodothyronine (T3) is the most active thyroid hormone and has up to ten times the activity of T4 and binds to receptors with a stronger action. Up to 80 percent of T4 is converted to T3 by organs, including the liver, kidney, and spleen. T4 is a precursor hormone used to make T3.
Calcitonin is a thyroid hormone involved in the balance of blood calcium levels. It lowers the amount of calcium and phosphate in the blood as needed, by inhibiting bone breakdown and accelerating the assimilation of calcium. Thus, the thyroid is also involved in bone health and diseases such as osteoporosis.
In women, the ovaries have receptors for thyroid hormone. This thyroid-ovary connection is the reason why women with low thyroid often suffer ovulation problems, infertility and recurring miscarriages, severe menstrual problems and heavy periods.
Unfortunately, too many people have undiagnosed—and unaddressed—low thyroid function. Common symptoms include:
- Cold hands and feet
- Depression and irritability
- Hair loss, and/or dry, coarse skin and hair,
- Edema (swelling of eyelids or face)
- High TSH, over two (see following)
- Impaired memory
- High cholesterol
- Irregular heartbeat or slow pulse
- Slower metabolism (may show up as weight gain)
- In women PMS, severe menopause symptoms, increased risk of breast cancer, cysts (breast and ovarian)
Testing Thyroid Function
If you have many of the symptoms mentioned above, it is best to have your thyroid hormones checked. A diagnosis of clinical hypothyroidism (low thyroid) is made when a TSH blood test shows that TSH levels are higher than 5.5 to 6.0. High TSH levels indicate hypothyroidism because the pituitary is pumping out TSH in an effort to stimulate the thyroid into action.
The range of normal for most TSH tests, depending on where you live, is 0.5 to 5.5 or 6.0. However, many labs are adjusting “normal” reference ranges to show that a TSH above 2.0 is indicative of low thyroid function, as this suboptimal function can also cause classic symptoms of hypothyroidism.
If your TSH is above 2.0, it is important to make diet and lifestyle changes that promote thyroid health and to stave off additional complications as you age.
Thyroid and Your Heart
Heart disease is the leading North American killer, yet few people realize that low thyroid function can worsen heart disease and its symptoms.
When the thyroid doesn’t produce enough thyroid hormone, the heart muscle cannot contract and relax effectively, thus inhibiting its pumping strength. If unaddressed, diastolic dysfunction can occur, whereby the heart ventricles “stiffen,” resulting in irregular blood flow and pooling. In serious cases, blood pools in the organs, mainly in the lungs, causing congestion and possible heart failure.
Low thyroid function further increases C-reactive protein, a marker for chronic inflammation. Thyroid hormones are also very important in cholesterol metabolism. People with severe hypothyroidism have higher elevated total and LDL cholesterol and, in 2003, the American Thyroid Association noted that even mild cases of low thyroid can elevate blood cholesterol. It is believed that a lack of thyroid hormones incites the liver to produce more cholesterol—possibly as a protective measure—and, at the same time, inhibits its breakdown.
Symptoms related to the cardiac-thyroid connection include:
- A slow or irregular heart beat, or heart palpitations (thyroid modulates heart beat)
- Shortness of breath and inability to exercise (caused by weakened muscles)
- High diastolic blood pressure (due to stiffer arteries)
- Swelling (edema; often a symptom of heart failure)
- Worsening of heart failure
- High cholesterol
- Hastening of atherosclerosis.
Thyroid and Menopause
Many of the symptoms women suffer at menopause are due to low thyroid and/or exhausted adrenals (see sidebox on page 42). Unfortunately, most women are given synthetic estrogen for their complaints, which further shuts down the thyroid because high estrogen levels interfere with thyroid hormones, particularly the utilization of T3. Weight gain and increased blood pressure are common side-effects of synthetic estrogens because, when the estrogen blocks thyroid hormone, the body’s metabolic rate slows down, making it very difficult to lose weight.
Depression and fatigue are the most common low thyroid symptoms in menopausal women. Often the prescription is antidepressants or hormone replacement therapy or both, when thyroid hormones would be more appropriate. The correlation between low thyroid and the rise of emotional symptoms needs to be better publicized to protect women from unnecessary side-effects of antidepressant medications, including low libido, vaginal dryness, weight gain and hot flashes. Ironically, many of these are the same symptoms that women are trying to treat during the transitional years.
Foods for Thyroid Health
Support hormone health by adopting the following dietary recommendations. Eat high-quality free-range, organic or wild protein. Your plate at lunch and dinner should contain a piece of protein and lots of green vegetables. Breakfast should be predominantly protein, such as boiled or poached free-range eggs, a protein shake, yogurt with protein powder added, or a chicken breast.
Avoid refined foods at breakfast, including breads and cereals, and concentrated carbohydrates such as instant oatmeal and fruit juices.
The thyroid needs iodine to make thyroid hormones. Iodine-rich foods include beef, lamb, and beef liver (hormone-free); eggs; raw nuts and seeds; seafoods (such as clams, oysters, sardines, and other saltwater fish); sea vegetables (such as wakame, hijiki, kelp, nori, arame, and dulse); and fresh fruits and vegetables, especially green peppers, lettuce, and pineapple. Raisins contain iodine as well.
Avoid all soy foods as they contain goitrogens, which cause a decrease in iodine absorption.
Use only pure, cold-pressed organic oils, including flaxseed, extra virgin olive oil, echium, borage, and sesame. Avoid all artificial sweeteners, including sucralose and aspartame. Use only natural sweeteners like xylitol and stevia. Exercise daily for 20 minutes, if possible, as this stimulates the thyroid gland and increases metabolism.
Supplements for Thyroid Support
Some women find that nutritional supplements can help thyroid hormone levels normalize quickly without medications. Or, if you are like many who are already taking thyroid medications but find, after a time, that your symptoms return, you may not be converting your T4 thyroid hormone to T3, and you will also benefit from the following thyroid support nutrients. These are not to be used in place of the thyroid hormone your doctor has prescribed, but in addition to it. Please note that they do not apply to hyperthyroid (overactive thyroid). This complicated condition is best treated by an endocrinologist.
L-tyrosine is an essential amino acid necessary for the manufacture of the thyroid hormones T4 and T3. Dietary sources of l-tyrosine are mainly derived from animal and vegetable proteins. Vegetables and juices contain small amounts, as do fermented foods such as yogurt and miso. It is also available in supplement form.
Ashwagandha has long been used in Ayurvedic medicine to support the thyroid gland. Animal studies show that it enhances thyroid function and produces a significant increase in T4. Ashwagandha is also well known in India for its endocrine effects of enhancing sexual desire. We know that when the thyroid is low, sex drive disappears, so this action likely has more to do with enhancing T4 thyroid hormone.
Guggals, an herb, supports complete thyroid health while enhancing the conversion of T4 to T3. Look for a formula that contains both ashwagandha and guggals as they have a synergistic effect.
Iodine is essential for the manufacture of thyroid hormones. Unfortunately, now that table salt is being eliminated from the diet due to fears of high blood pressure, North Americans often do not get enough potassium iodide to support proper thyroid function. The adrenal glands also require sodium for optimal health.
Pantothenic acid is a supporting nutrient for thyroid hormone manufacture. It also supports the adrenal glands, increases energy and helps you better handle stress.
Minerals such as copper, manganese, and selenium are also necessary for the proper manufacture of thyroid hormones. Additionally, a deficiency in several nutrients can cause or contribute to hypothyroidism, so supplement with a good multivitamin that includes the vitamins A, B2, B3, B6, C, D, and E, plus minerals.
Because thyroid hormones regulate every cell in every organ, keeping your thyroid healthy and your levels of thyroid hormones balanced is the key to a vibrant life.