More than 10 million Americans have been diagnosed with thyroid disease, and another 13 million people are estimated to have undiagnosed thyroid problems. About 10 percent of the adult population is afflicted with this frequently overlooked disease of epidemic proportion. A dysfunctional thyroid can affect almost every aspect of health.It is one of the most under-diagnosed hormonal imbalances of aging, together with estrogen dominance and syndrome X.

Thyroid Basics

Thyroid is a small butterfly-shaped gland that wraps around the windpipe. The cells inside the thyroid takes in the iodine, obtained through food, iodized salt, or supplements, and combines that iodine with the amino acid tyrosine. The thyroid then converts this into the hormones thyroid hormones called T3 and T4.

Once released by the thyroid, the T3 and T4 travel through the bloodstream. Under normal conditions, 80 percent of thyroid hormones are in the form of and T4 and 20 percent in the form of T3. T3 is the biologically more active and is several times stronger than T4. The conversion of T4 to T3 takes place both inside the thyroid as well as in some organs other than the thyroid, including the hypothalamus, a part of your brain.

The thyroid gland acts like the body's barometer. Its main function is to help cells convert oxygen and calories into energy. It regulates:

• Heart rate
• Blood pressure
• Body temperature
• Metabolism
• Growth


Thyroid, like other hormones, is regulated by an extensive negative feedback system. The system starts in the hypothalamus of the brain that releases Thyrotropin-releasing Hormone (TRH). TRH signals the pituitary gland to release Thyroid Stimulating Hormone (TSH).  TSH in turn instructs the thyroid gland to make thyroid hormones and release them into the bloodstream. When the level of thyroid hormone in your body is high, a negative feedback system exists to reduce the production of TSH, and vice-versa. Therefore, a high TSH is indicative of hypothyroidism, while a low TSH can be indicative of hyperthyroidism.


Causes of Hypothyroidism

There are a variety of factors that can contribute to the development of thyroid problems:

• Exposure to external radiation such as occurred after the Chernobyl nuclear plant accident.

• Over-consumption of isoflavone-intensive soy products such as soy protein or powder. Isoflavones act as potent anti-thyroid agents, and are capable of suppressing thyroid function, and causing or worsening hypothyroidism.

• Some anti-thyroid drugs, such as lithium and the heart drug cordarone.

• History of radiation treatment to the head and neck area.

• Over-consumption of uncooked "goitrogenic" foods, such as broccoli, turnips, radish, cauliflower, and Brussels sprouts.

• Radioactive iodine treatment for hyperthyroidism/Graves' Disease.

• Post-surgical removal of all or part of the thyroid due to nodules or cancer.

• Adrenal insufficiency (commonly caused by chronic stress).

• Mercury intoxication (amalgams are 50% mercury). Amalgam fillings have been associated with a variety of problems such as Alzheimer's disease, infertility, neurotransmitter imbalances, and thyroid problems.


Risk of Hypothyroidism

You have a higher risk of developing thyroid disease if, among a variety of factors,

…You have a family history of thyroid problem
…You have a history of  Chronic Fatigue Syndrome
…You are a  female and over menopausal
…You are over age 60
…You have been exposed to radiation or certain chemicals (i.e., perchlorate, fluoride)

Associated Disease

As many as 10 percent of 98 million Americans with high cholesterol and high LDL ("bad") cholesterol may not know that their cholesterol is high due to undiagnosed thyroid problem. Older women with sub clinical or under-active hypothyroidism was shown to be twice as likely as women without this condition to have heart attacks.

Thyroid disease is also intricately  tied to adrenal gland and ovarian function.



Symptoms of Low Thyroid

Being one of the master regulators of body metabolism, symptoms of low thyroid function generate a global response. Symptoms include:

• Fatigue and low energy, with need for daytime nap.
• Depressed, down, or sad.
• Skin that becomes dry, scaly, rough, and cold.
• Hair becomes coarse, brittle, and grow slow.
• Excessive unexplained hair loss.
• Sensitivity to cold in a room when others are warm.
• Difficulty in sweating despite hot weather.
• Constipation that is resistant to magnesium supplementation.
• Difficulty in loosing weight.
• Unexplained weight gain.
• High cholesterol resistant to cholesterol lowering drugs.


Diagnosis: Standard Laboratory Test

A popular way of diagnosing hypothyroidism is using basal body temperature. Dr. Broda Barnes, M.D, popularized this test. While using basal body temperature can be better than using the standard thyroid function test, it comes with certain disadvantages, including:

• Falsely elevated temperature when sleeping under eclectic blanket
• Poor compliance
• Accurate thermometer required

Most clinicians rely on blood test instead. The traditional laboratory tests used to diagnose hypothyroidism are:

• Total T4
• T3 Uptake and
• Free Thyroxin Index (FTI)
• TSH (Thyroid Stimulating Hormone)


Due to the complexity and inherent weakness of the traditional laboratory tests, there is widespread difficulty in their interpretation.

The key test is TSH. The lower the amount of thyroid hormone in the body, the more TSH will be produced and secreted by the pituitary to stimulate the thyroid gland to put out thyroid hormones. A low TSH signals enough TSH on board, while a high TSH signals a deficiency of TSH in the body.


For most traditional laboratories, the upper limits of normal TSH level is under 4.0 to 4.5. While those who have TSH higher than 4.5 is highly likely to have hypothyroidism, many more with TSH under 4.5 have sub-clinical hypothyroidism or under-active thyroid. The clinician easily misses these cases if the focus on diagnosis is based on the traditional reference range only. Many with a TSH under 4.0 are in fact symptomatic and may well be hypothyroid. In other words, the traditions normal range is far too insensitive to detect hypothyroidism, especially those in the sub-clinical stage of the disease with symptoms.

The myth that an elevated TSH level (the upper limits of normal range by normal laboratory reference range is under 4.5) is required, as prerequisite for diagnosis of hypothyroidism must be dispelled. There is little doubt that an elevated TSH signifies and under active thyroid as the pituitary gland secretes TSH in response to a low thyroid hormone level. The real question is - how high a TSH is considered high?



New Diagnostic Reference Standard for TSH

There are doctors who believe that you do not need to have an elevated TSH level (higher than 4.5) in order to actually be diagnosed and treated for hypothyroidism. Increasingly, innovative doctors are also viewing high-normal or normal TSH levels (by traditional standards) as possible evidence of low-level hypothyroidism, especially if symptoms of hypothyroidism are present.

The traditional normal laboratory range is relative. Many, especially women, have symptoms -- or are hypothyroid -- when TSH is anywhere but at the lower end of the normal range or 2 or thereabouts.

Many patients with TSH level of 2.0 (not 4.5) or more have classic symptoms and signs of hypothyroidism. Even though their TSH is considered "normal" by traditional standards, many are suffering from under active thyroid or sub-clinical hypothyroidism. If your routine blood work comes back with a TSH of 2.0 and you have symptoms of hypothyroidism, ask your doctor! Chances are your thyroid gland is not working properly.

TSH alone, however, is not an accurate test of all forms of hypothyroidism but only primary hypothyroidism. Addition tests like Free T3 (FT3) and Free T4 (FT4) are required. Some doctors also test for elevated thyroid antibodies in addition to FT3 and FT4. Many patients, especially women with elevated antibodies are in the process of developing autoimmune thyroid disease. Early detection is important to effect appropriate treatment. Even with normal TSH levels, the majority of symptomatic women with elevated antibodies, low FT3 and low FT4 require thyroid hormone replacement to feel well.


Free T3 and Free T4

Thyroid gland produces four thyroid hormones called T1, T2, T3, and T4. The number indicates the number of iodine molecules attached to the molecule. T 4 is what synthetic thyroid such as Synthroid has. T4 is a hormone precursor and is converted into T3, the form that performs most of the thyroid function in the body. Thinking that synthetic thyroid proves steady hormone levels, it is widely prescribed by doctors. Easily overlooked is the fact that many people cannot convert the T4 to T3. This is easily confirmed by measure free hormone level, a practice most doctors are not trained on.

Free T3 and Free T4 are the only accurate measurement of the actual active thyroid hormone levels in the body. This is the hormone that is actually free and exerting effect on the cells. These are the thyroid hormones that count.

It is common to find Free T3 and Free T4 below normal when TSH could in the normal range or in the low end of the normal range. This is indicative of secondary or tertiary hypothyroidism. This is normally thought of as due to hypothalamus or pituitary dysfunction, resulting in the body's inability to convert T4 to T3.

New Laboratory Reference of Hypothyroidism

1. If your FT4 is less than 0.7 (normal 0.7 to 2.0).
2. If FT3 is less than 2.3 (normal 2.3 to 4.2).
3. If your TSH is above 2.0

Ask for these tests. If your thyroid test results come back and your doctor is not sure what it means, consider going to a reputable holistic physician or alternative physician for further interpretation and diagnosis.

Treatment

The traditional standard treatment for hypothyroidism for decades is synthetic T4 hormone levothyroxine, such as levoxyl and Synthroid.

Alternative physicians prefer  Amour Thyroid that contain natural thyroid hormones. Natural hormones also have T1 and T2 in addition to T3 and T4. Armour thyroid is a natural desiccated thyroid. It was the only available treatment for hypothyroidism for some 50 years. Because of concern about their variable potency, these extracts have been considered obsolete for some time by all but a few natural prescribers.

Armour thyroid needs to be taken twice a day to provide the adequate and consistent blood level of T3, which is shorter than that of T4. The common starting dose is 90 mg cut in half and taken one half after dinner and the other half after breakfast. Repeat blood test should be performed after one month and dosage adjusted accordingly to maintain TSH under 0.5. Free T3 and Free T4 should be maintained above the median but below the upper end of the laboratory normal reference range.

Optimum FT3 and FT4 anti-aging range for healthy young adults is towards the top end of normal range, while for the elderly is towards the middle of normal range. Once TSH, free T3 and free T4 targets are reached, annual checkup is warranted. Overweight and thyroid resistant patients might need to have their dosage increased.

While synthetic thyroid hormone made in the laboratory by drug companies usually contain T3 (Cytomel) and T4 (levothyroxine) or combinations (Thyrolar) of these two. Patients with hypothyroidism show greater improvements in mood and brain function if they receive treatment Armour thyroid rather than Synthroid (thyroxin). Research reported in the New England Journal of Medicine in February of 1999 found that a majority of patients, however, might feel better on a combination of hormones such as combination of T3 and T4 instead of single T4 alone.


Those that do not wish to take thyroid replacement may consider non-commercially harvested seaweeds as the best source of organically bound iodine. 5 grams a day is needed, or about 1 ounce per week. A pound would last about two months. If you cannot get good seaweed, consider kelp supplement as alternative.


What to do if you are already on Synthroid?

If you are on Synthroid (T4), chances are your Free T4 is at or above the high end of normal range and your Free T3 is below. You may wish to add 5 - 12.5 mg Cytomel (pure T3) after breakfast and after dinner rather than Armour thyroid or Thyrolar (synthetic T4/T3 combination).

Summary

Hypothyroidism is one of the most under-diagnosed diseases of the aging process. Traditional laboratory tests are outdated and highly insensitive. Proper diagnosis of thyroid disease requires a careful history and physical examination, accompanied by laboratory studies such as  TSH, Free T3 and Free T4.  The use of newer and more sensitive laboratory ranges is critical in the proper interpretation of these test. Most patients requiring treatment will do well on natural thyroid replacement

The thyroid, adrenal, and ovarian axis requires intricate balance all the time. Factors that upset this balance, including female hormonal imbalance, excess intake of estrogen-like compounds such as soy, and adrenal stress can cause hypothyroidism. 

Treatment of thyroid diseases must take into consideration the other the hormonal systems, including rebalancing  of female hormones with estrogen and progesterone, and modulation of adrenal function with natural hormones such as pregnenolone and DHEA.