Primary Causes & Action Plans

TPO Antibodies (Thyroid Peroxidase)

Markers of thyroid autoimmune attack; high titers indicate aggressive disease
TPO antibodies attack thyroid peroxidase enzyme, directly damaging thyroid tissue. Higher TPO antibody titers correlate with faster thyroid decline. Monitoring TPO levels indicates disease activity.
Target < 35 IU/mL
Suggested Action Plan

Lower TPO antibodies through selenium supplementation (200 mcg daily), vitamin D optimization (60-80 ng/mL), zinc (15-30 mg daily), and anti-inflammatory diet. Retest every 3-6 months.

TgAb (Thyroglobulin Antibodies)

Markers of thyroid autoimmune attack; indicates ongoing thyroid destruction
Thyroglobulin antibodies attack thyroid protein directly, causing tissue destruction. Like TPO antibodies, higher TgAb titers correlate with more aggressive disease. Both TPO and TgAb should be monitored.
Target < 40 IU/mL
Suggested Action Plan

Strategies to lower TgAb are similar to TPO: selenium, vitamin D, zinc, anti-inflammatory diet, stress management, and gut healing (leaky gut drives autoimmunity). Retest every 3-6 months.

TSH

Indicates degree of thyroid hormone deficiency; guides replacement dosing
TSH rises as thyroid function declines due to autoimmune destruction. TSH level guides levothyroxine dosing. Most people feel best with TSH between 1.0-2.5 mIU/L, not at the higher end of normal.
Target 1.0 - 2.5 mIU/L
Suggested Action Plan

If TSH is elevated, levothyroxine replacement is necessary. Start low (25-50 mcg daily) and increase gradually every 6-8 weeks. Target TSH of 1.0-2.0. Once optimized, retest annually.

Free T4

The active form of thyroid hormone; should be optimal on replacement therapy
Free T4 is the biologically active thyroid hormone. Most people feel better with free T4 in the upper-normal range (1.0-1.5 ng/dL). If TSH is normal but free T4 is low, increase levothyroxine dose.
Target 1.0 - 1.5 ng/dL
Suggested Action Plan

If symptoms persist despite "normal" TSH, check free T4 level and adjust levothyroxine accordingly. Some people need T3 added (as combination therapy) if free T4 is low normal.

Free T3

The most active thyroid hormone; measures peripheral thyroid hormone action
Free T3 is converted from T4 in tissues and is the most biologically active form. Some people with low energy on levothyroxine alone have low free T3 due to impaired conversion. Adding T3 helps.
Target 3.0 - 4.0 pg/mL
Suggested Action Plan

If free T3 is low despite adequate free T4, consider adding liothyronine (synthetic T3) or desiccated thyroid (which contains both T4 and T3). Retest after 4-6 weeks of combination therapy.

Also in Autoimmune

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TSH Guide
Thyroid Disorders
Free T3 Guide
Hypothyroidism

Getting Started

1
Get Comprehensive Hashimoto's Testing

Test TPO and TgAb antibodies, TSH, free T4, and free T3. High antibody titers indicate aggressive autoimmunity; hormone levels guide replacement. Both are essential.

2
Start or Optimize Thyroid Hormone Replacement

Most people with Hashimoto's require levothyroxine. Work with a thyroid-knowledgeable doctor to achieve TSH between 1.0-2.0 and free T4 in the upper-normal range. This often requires higher doses than standard care provides.

3
Suppress Autoimmune Attack Through Nutrition

Take selenium 200 mcg daily (reduces TPO antibodies). Supplement vitamin D to 60-80 ng/mL. Take zinc 15-30 mg daily. Avoid iodine supplementation unless deficient (can worsen autoimmunity).

4
Adopt Anti-Inflammatory Diet and Lifestyle

Eliminate gluten (associated with thyroid autoimmunity). Heal leaky gut if present (probiotics, L-glutamine, bone broth). Manage stress and sleep. Exercise regularly. These interventions reduce antibody titers.

5
Retest Antibodies Every 3-6 Months

TPO and TgAb antibodies should decline over 6-12 months with comprehensive intervention. Lower antibody titers correlate with slower thyroid decline. Retest to confirm immune tolerance is improving.

Why I built this guide.

"Hashimoto's is manageable when you treat both the autoimmunity and the hormone deficiency. Testing both antibodies and thyroid hormones is essential."

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