Hashimoto’s Thyroid Panel | TSH, T3, T4, Reverse T3 & TPO
$229.00
Comprehensive thyroid testing for Hashimoto’s and persistent hypothyroid symptoms, including TSH, Free T4, Free T3, Total T4, Total T3, reverse T3 and TPO antibodies. Evaluates thyroid signaling, hormone availability, autoimmune activity and T4-to-T3 metabolism while explaining how this broader approach differs from conventional TSH-based screening.
Description
Hashimoto’s thyroiditis and hypothyroidism are related, but they are not the same diagnosis.
Hypothyroidism describes inadequate thyroid hormone effect or production. Hashimoto’s thyroiditis describes an autoimmune process in which the immune system targets thyroid tissue, most commonly producing thyroid peroxidase antibodies and/or thyroglobulin antibodies.
A person can therefore have Hashimoto’s while TSH and thyroid hormone levels are still normal. Over time, autoimmune inflammation may progressively impair thyroid function and eventually produce hypothyroidism.
This panel looks beyond a single TSH measurement to evaluate thyroid signaling, hormone production, T4-to-T3 physiology and autoimmune activity.
Why Test More Than TSH?
TSH is an important test. It is the pituitary gland's signal telling the thyroid how strongly it should produce thyroid hormone.
For straightforward primary hypothyroidism, TSH together with Free T4 remains the conventional foundation of diagnosis.
But TSH alone does not answer every clinical question.
Is Hashimoto’s Present?
A normal TSH does not exclude thyroid autoimmunity. Antibody testing looks for evidence that the immune system is targeting the thyroid gland.
How Much T4 and T3 Are Present?
Free and total hormone measurements provide information that cannot be obtained from the pituitary TSH signal alone.
Why Are Symptoms Persisting?
Persistent fatigue, cold intolerance, poor exercise tolerance, hair loss or brain fog may require looking beyond thyroid disease alone to conversion, illness, nutrition, inflammation and other metabolic causes.
Hashimoto’s vs Hypothyroidism
| Hashimoto’s Thyroiditis | Hypothyroidism | |
|---|---|---|
| What it describes | An autoimmune disease directed against thyroid tissue. | Insufficient thyroid hormone production or effect. |
| Can thyroid hormones initially be normal? | Yes. Autoimmune activity may begin while TSH and Free T4 remain within range. | By definition, established primary hypothyroidism eventually produces an abnormal thyroid-function pattern. |
| Common laboratory clues | TPO antibodies and/or thyroglobulin antibodies; thyroid ultrasound may show inflammatory changes. | Most commonly elevated TSH with low Free T4 in overt primary hypothyroidism. |
| Relationship | Hashimoto’s is the most common cause of hypothyroidism in the United States. | Hypothyroidism can also result from thyroid surgery, radioactive iodine, medication, iodine problems, pituitary disease and other causes. |
What This Panel Measures
TSH
Thyroid-Stimulating HormoneTSH is produced by the pituitary gland and acts as the primary regulatory signal to the thyroid.
When circulating thyroid hormone falls, the pituitary usually responds by producing more TSH. This is why an elevated TSH is a hallmark of primary hypothyroidism.
- High TSH: commonly suggests the thyroid gland needs stronger stimulation to maintain hormone production.
- Low TSH: may occur with hyperthyroidism, excessive thyroid replacement or certain pituitary/hypothalamic problems.
- Normal TSH: is reassuring in many situations but does not tell us whether thyroid antibodies are present.
Think of TSH as the instruction signal. It tells us how strongly the pituitary is asking the thyroid to work, not whether the thyroid is autoimmune.
Free T4
Available ThyroxineT4 is the major hormone secreted by the thyroid gland. Much of circulating T4 is bound to transport proteins; Free T4 measures the unbound portion available to tissues.
Free T4 is particularly useful when interpreted with TSH.
- Helps confirm overt hypothyroidism when TSH is elevated.
- Can identify central or pituitary-pattern hypothyroidism when Free T4 is low but TSH is not appropriately elevated.
- Helps assess thyroid hormone replacement.
- Is less affected by changes in binding proteins than Total T4.
Free T4 tells us more about the available hormone supply than TSH alone.
Free T3
Active TriiodothyronineT3 is the more biologically active thyroid hormone at thyroid-hormone receptors. Most circulating T3 is not secreted directly by the thyroid; it is produced by removing an iodine atom from T4 in peripheral tissues.
T3 influences:
- Metabolic rate
- Heat production
- Heart rate
- Muscle function
- Brain and mood function
- Energy expenditure
A lower Free T3 value can occur during illness, calorie restriction, severe stress and other states that alter thyroid-hormone metabolism.
Reverse T3
Inactive T4 MetaboliteReverse T3 is formed when T4 is converted through a different deiodination pathway than the one that produces active T3.
Reverse T3 is biologically inactive and commonly rises during situations such as:
- Acute or chronic illness
- Calorie restriction or fasting
- Major physiologic stress
- Inflammatory illness
- Changes in peripheral thyroid-hormone metabolism
From a functional perspective, rT3 can provide context about how the body is partitioning T4 metabolism between active T3 and inactive metabolites.
Total T4
Bound + Free ThyroxineTotal T4 measures both protein-bound and unbound T4.
Because most thyroid hormone travels attached to transport proteins, Total T4 may change when thyroid-binding proteins change.
This can occur with:
- Pregnancy
- Estrogen therapy
- Oral contraceptives
- Liver disease
- Changes in thyroid-binding globulin
Comparing Total T4 with Free T4 can therefore help distinguish a true hormone abnormality from a change in protein binding.
Total T3
Bound + Free T3Total T3 measures the total circulating pool of T3, including hormone attached to transport proteins.
It is particularly helpful when hyperthyroidism is suspected because some patients develop T3-predominant hyperthyroidism before Free T4 becomes elevated.
Total T3 also provides useful comparison with Free T3 when binding-protein abnormalities or assay discrepancies are suspected.
It is less useful as a stand-alone test for diagnosing hypothyroidism because T3 may remain normal until later in thyroid failure.
TPO Antibodies
Thyroid Peroxidase AntibodiesThyroid peroxidase is an enzyme used by thyroid cells to manufacture thyroid hormone.
In Hashimoto’s thyroiditis, the immune system may produce antibodies directed against TPO.
An elevated TPO antibody level supports the presence of autoimmune thyroid disease.
- Autoimmune activity can exist before hypothyroidism develops.
- TSH and Free T4 may remain normal during earlier Hashimoto’s.
- Thyroid function may change over time as autoimmune injury progresses.
- TPO positivity helps distinguish autoimmune thyroiditis from many other causes of abnormal thyroid function.
TPO antibody concentration does not directly tell us how much thyroid function has been lost. Thyroid function itself is followed primarily with TSH and Free T4.
What About Thyroglobulin Antibodies?
Hashimoto’s can produce antibodies against thyroglobulin (TgAb) as well as TPO.
Some patients with autoimmune thyroiditis are TPO-negative but TgAb-positive. For that reason, thyroglobulin antibodies can be useful when suspicion for Hashimoto’s remains high despite negative TPO antibodies.
How Hashimoto’s Can Develop Before TSH Becomes Abnormal
Immune Activation
TPO and/or thyroglobulin antibodies may appear.
Thyroid Inflammation
Autoimmune activity affects thyroid tissue.
Compensation
The thyroid may still produce enough hormone to maintain normal TSH and Free T4.
Loss of Reserve
As functional thyroid tissue is lost, TSH may rise and overt hypothyroidism can develop.
This is one of the clearest differences between testing for thyroid function and testing for the cause of thyroid disease.
Conventional Thyroid Testing vs a Broader Thyroid Evaluation
| Question | Conventional Evaluation | Broader Functional Evaluation |
|---|---|---|
| Is primary hypothyroidism present? | TSH, often with reflex Free T4. | TSH and Free T4 remain foundational. |
| Is Hashimoto’s the cause? | TPO and/or Tg antibodies when autoimmune disease is suspected. | Antibodies are considered early when symptoms, family history or fluctuating function suggests autoimmunity. |
| What is happening with T3? | T3 is usually not needed for routine hypothyroidism diagnosis. | Free and/or Total T3 may provide additional context about peripheral hormone metabolism. |
| What about reverse T3? | Not recommended routinely. | Sometimes considered in persistent symptoms, severe physiologic stress or patients already taking T4, while recognizing its limitations. |
| What else may influence symptoms? | Further investigation if thyroid results do not explain symptoms. | Earlier consideration of iron, B12, vitamin D, zinc, selenium, cortisol/stress physiology, inflammation, gut health, mitochondrial function and metabolic factors. |
The Broda Barnes Approach to Hypothyroidism
Dr. Broda O. Barnes was a physician whose work strongly influenced later functional and integrative approaches to thyroid disease.
Barnes believed that laboratory testing alone could miss clinically important low thyroid function. He placed greater emphasis on the patient's symptoms and basal body temperature.
Clinical Pattern First
Barnes emphasized fatigue, cold intolerance, weight problems, constipation, dry skin, menstrual changes, depression and other clinical features rather than relying solely on a laboratory cutoff.
Basal Axillary Temperature
His method typically used morning axillary temperature before getting out of bed. An average below approximately 97.8°F was considered suggestive of reduced thyroid function, while roughly 97.8–98.2°F was considered his preferred range.
Clinical Response
Barnes also considered response to thyroid hormone, traditionally desiccated thyroid containing both T4 and T3, as part of his clinical model.
However, the broader lesson from Barnes remains useful: thyroid laboratory results should be interpreted together with symptoms and physiology rather than in isolation.
Where the Barnes Approach and Modern Testing Can Complement Each Other
Rather than choosing between symptoms and laboratory testing, a more useful approach is to combine them.
Objective Testing
- TSH
- Free T4
- Thyroid antibodies
- Free / Total T3 when useful
- Reverse T3 selectively
- Ultrasound when indicated
Clinical Physiology
- Cold intolerance
- Basal temperature trends
- Energy and exercise tolerance
- Weight and metabolic changes
- Hair, skin and bowel changes
- Mood and cognition
If symptoms and laboratory findings disagree, that discrepancy should prompt further investigation rather than assuming either the laboratory or the symptoms must automatically be wrong.
Why T4-to-T3 Conversion Matters
The thyroid produces predominantly T4. Much of the biologic thyroid effect throughout the body depends on peripheral conversion of T4 into T3.
Conversion is influenced by several factors, including:
- Overall calorie and carbohydrate availability
- Acute and chronic illness
- Inflammation
- Liver function
- Kidney function
- Selected medications
- Selenium status
- Iron status
- Severe physiologic stress
Nutrients Important for Thyroid Physiology
Iodine
Iodine is incorporated directly into T4 and T3. Both deficiency and excessive iodine can disturb thyroid function, particularly in susceptible autoimmune thyroid disease.
Selenium
Selenium-dependent deiodinase enzymes participate in thyroid-hormone metabolism, and selenium-dependent antioxidant systems help protect thyroid tissue from oxidative stress.
Iron
Adequate iron is important for thyroid peroxidase activity. Iron deficiency can also independently produce fatigue, hair loss and exercise intolerance that resemble hypothyroidism.
Zinc
Zinc participates in thyroid-hormone signaling and numerous enzymes involved in metabolism and immune regulation.
Vitamin D
Vitamin D is relevant to immune regulation and is often considered in patients with autoimmune conditions, although correcting deficiency is not itself a treatment for Hashimoto’s.
Vitamin B12
B12 deficiency can mimic several thyroid symptoms, including fatigue, cognitive changes and neurologic complaints.
Hashimoto’s Is an Immune Disorder, Not Just a Thyroid Hormone Problem
Once Hashimoto’s is identified, simply knowing the thyroid hormone level does not explain why autoimmunity developed.
A broader evaluation may consider:
- Family history of autoimmune disease
- Celiac disease
- Other autoimmune disorders
- Vitamin D status
- Iron and B12 status
- Excess or deficient iodine exposure
- Gut and inflammatory disorders
- Medication effects
- Pregnancy and postpartum immune changes
Not every suspected “immune trigger” has been proven to cause Hashimoto’s, so these findings should be interpreted individually rather than assuming that every patient requires an extensive detoxification or elimination protocol.
Symptoms That May Justify a More Complete Thyroid Evaluation
Energy & Temperature
- Persistent fatigue
- Cold hands or feet
- Low body temperature
- Poor exercise tolerance
- Sluggish recovery
Metabolic & Physical
- Unexplained weight gain
- Constipation
- Dry skin
- Hair thinning
- Muscle aches
Mood & Cognitive
- Brain fog
- Reduced concentration
- Low motivation
- Depressive symptoms
- Slowed thinking
What This Panel Can Help Clarify
- Whether the laboratory pattern supports primary hypothyroidism
- Whether Hashimoto’s autoimmune thyroid disease is present
- Whether thyroid hormone levels are discordant with TSH
- Whether Total and Free hormone measurements differ because of binding effects
- Whether T3 availability provides additional context for persistent symptoms
- Whether reverse T3 is elevated in a clinical setting where altered peripheral metabolism is plausible
- Whether additional thyroid antibody or ultrasound evaluation may be appropriate
Frequently Asked Questions
Can you have Hashimoto’s with a normal TSH?
Yes. Hashimoto’s is an autoimmune disease and thyroid antibodies may be present while TSH and Free T4 remain normal. Thyroid function can decline later as autoimmune injury progresses.
Can you have hypothyroidism without Hashimoto’s?
Yes. Hashimoto’s is the most common cause of hypothyroidism in the United States, but thyroid surgery, radioactive iodine, medications, iodine abnormalities, pituitary disease and other conditions can also cause hypothyroidism.
Why test TPO antibodies?
TPO antibodies help determine whether autoimmune thyroid disease is responsible for the thyroid problem. This answers a different question from TSH, which primarily reflects pituitary signaling to the thyroid.
What if TPO antibodies are negative?
Negative TPO antibodies make Hashimoto’s less likely but do not completely exclude autoimmune thyroiditis. Thyroglobulin antibodies and, in selected cases, thyroid ultrasound may provide additional information.
Why test Free T3?
Free T3 provides additional information about circulating active thyroid hormone. It can be useful in selected clinical situations, although it is not considered a primary diagnostic test for hypothyroidism and Free T3 assays have technical limitations.
Why test reverse T3?
Reverse T3 reflects an inactive pathway of T4 metabolism and may rise with illness, calorie restriction and physiologic stress. Its routine clinical value is controversial, so it should be interpreted as supplemental information rather than as a stand-alone diagnosis of hypothyroidism.
What was Dr. Broda Barnes' temperature approach?
Broda Barnes emphasized symptoms together with morning basal axillary temperature. He generally considered an average below about 97.8°F suggestive of reduced thyroid function. This approach remains influential in integrative medicine but is not accepted as a substitute for modern thyroid laboratory testing.
Why can someone still feel hypothyroid when TSH is normal?
Many conditions produce symptoms that resemble hypothyroidism, including iron deficiency, anemia, sleep disorders, depression, low calorie intake, chronic illness, vitamin deficiencies, medication effects and mitochondrial or metabolic problems. The correct response is a broader evaluation rather than assuming that a normal TSH either explains or dismisses the symptoms.