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Brochure     Thyroid Symptoms Fact sheet

Blood tests, especially TSH (thyroid stimulating hormone) levels, have limited value in diagnosing hypothyroidism. Many individuals have “normal” TSH levels, yet still suffer with the classical symptoms of hypothyroidism:

  • Tiredness
  • Forgetfulness/slower thinking
  • Moodiness/irritability
  • Depression
  • Inability to concentrate
  • Hair loss
  • Loss of body hair
  • Loss of eyebrows
  • Dry, patchy skin
  • Weight gain
  • Swelling
  • Swollen eyes and face
  • Chronic pain
  • Headaches
  • Dizziness
  • Brain fog
  • Brittle nails
  • Cold intolerance
  • Constipation
  • Infertility
  • Menstrual irregularities/heavy periods
  • Slow heartbeat
  • High cholesterol

Likewise, when the level of TSH in the blood is used to determine the “ideal” dose of thyroid medication, many people still remain symptomatic. Since thyroid blood testing does not detect many cases of hypothyroidism, symptomatic individuals are often denied treatment that would greatly improve their health. Unfortunately, many physicians are not comfortable diagnosing hypothyroidism on the basis of a patient’s clinical symptoms, especially when their blood tests fall within the “normal” range. These physicians require objective evidence that a symptomatic individual is actually hypothyroid before offering treatment.

Physicians, as well as symptomatic individuals, must be made a aware of an alternate method of thyroid testing that can be used to confirm the diagnosis in symptomatic patients who have normal blood tests. For this reason, it is really of utmost importance to raise public awareness of THYROFLEX TESTING, a little known and underutilized method that can be used for making a diagnosis of hypothyroidism, and for determining the optimal dose of thyroid medication for symptomatic patients.

The Thyroflex Test, developed by Dr. Daryl Turner, is able to determine a person’s thyroid status based upon the measurement of conduction velocity through a tendon reflex. "What could the speed of nerve conduction possibly have to do with hypothyroidism? The connection was made late in the 19th century when doctors, studying patients with hypothyroidism, observed that clinically hypothyroid individuals had very slow or absent tendon reflexes. A tendon reflex is a movement of a muscle caused by the stimulation of a nerve that controls the muscle and causes it to move involuntarily. The speed at which this reaction occurs is an indicator of cellular function. The lower the speed of conduction, the lower the cellular energy and function.

Cellular function is ultimately controlled by T3, the most biologically active thyroid hormone. Low levels of T3 within the cells of the body result in diminished cellular function, which ultimately cause people to suffer with the clinical symptoms of hypothyroidism. Since blood tests cannot measure the level of intracellular T3 (level of T3 hormone located inside the cells), the best way to objectively test cellular function is by measuring the speed at which a nerve impulse is conducted through nerve and muscle cells. A slow rate of nerve conduction demonstrates low cellular function and confirms a diagnosis of hypothyroidism.

Thyroflex testing can also be used for establishing the optimal dose of thyroid medication for symptomatic individuals. Using the Thyroflex, a physician can immediately see if the patient’s dose of thyroid medication is adequate by the velocity of their nerve conduction. When slow nerve conduction is found with Thyroflex testing, an increase in the dose of thyroid medication is needed if the patient is symptomatic, irrespective of blood test results. This is especially true when a patient is taking Natural Desiccated Thyroid (NDT), since physicians unfamiliar with it are often confused by blood test results when patients are taking NDT.

There is an excellent correlation between Thyroflex results and patients’ clinical symptoms. As compared to Thyroflex testing, there is a poor correlation between TSH levels in the blood and patients’ symptoms since approximately 40% of patients on thyroid medication have TSH levels in the ideal range, but still experience symptoms.

How is this 5 minute Thyroflex testing performed?

The individual being tested is connected to the Thyroflex computer by placing a sensor above the middle knuckle of the left hand. A spot above the brachioradialis tendon (in the forearm) is identified, where the nerve will be stimulated. When stimulated, the tendon will make the middle finger move involuntarily. The time interval between the stimulation of tendon and the involuntary movement of the middle finger is measured by the computer. The average speed of conduction is calculated, indicating the level of intracellular thyroid function. This test causes no discomfort to patients.


The symptoms of hypothyroidism are the result of inadequate levels of T3 inside the cells of the body. Low levels of intracellular T3 cannot be detected by the levels of thyroid hormones in the blood. This is why blood thyroid hormone is not a good measurement of detecting hypothyroidism. In the hypothyroid state, low T3 levels within the cells cause the cells of the body to produce inadequate amounts of energy which result in the symptoms experienced by hypothyroid individuals. Slow nerve impulse speed, as indicated by Thyroflex testing, demonstrates low cellular function which correlates with clinical symptoms.

The bottom line is that diagnosing and treating hypothyroidism according to patient symptoms and results of the Thyroflex test is very effective. Knowledge of the many symptoms of hypothyroidism is the key to its diagnosis and treatment. However if a physician requires objective proof of the existence of hypothyroidism prior to treating symptomatic patients with normal blood tests, Thyroflex testing can  be used to confirm the clinical diagnosis. If a patient is being treated with thyroid medication and remains symptomatic, Thyroflex testing can immediately determine if an increase in dosage is needed to relieve the patient’s symptoms. Thyroflex testing is more sensitive then blood tests, in determining the optimal dose of thyroid medication.

Availability of Thyroflex Testing

SIBO CLINIC CANADA is just one of two clinics in Canada providing this test to anybody with or without a doctors referral. We are currently working on expanding to Calgary AB and Victoria BC in the very near future. Our Functional Medicine Consultant, Sandy Rideout is bringing the Thyroflex to Calgary AB in June 2019 to train practitioners on how to operate the Thyroflex and the importance of implementing it in their practice. This is very exciting news for many of you who have purchased the SIBO Breath Test kit from us in the last several months. Sandy will also be testing clients of various health professionals as well as any individual who contacts us that would like to be tested.  If you are an individual who would like to be tested please email us at info@sibocliniccanada.com