Not medical advice. I am a software engineer, not a physician. This page documents my own protocol and the research I read while building it. Talk to a qualified clinician before changing your supplementation, diet or any treatment. Lab reference ranges quoted here vary by laboratory and by individual.
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The thyroid is a butterfly-shaped gland located at the base of the neck that functions as the body's metabolic thermostat. It produces thyroid hormones (T4 and T3) that regulate the metabolic rate of virtually every cell in the body. These hormones control how fast you burn calories, how warm you feel, your heart rate, brain processing speed, and even how quickly you think. Thyroid dysfunction is remarkably common — affecting up to 12% of the population — and often presents with vague symptoms (fatigue, weight gain, brain fog) that are easily attributed to other causes, making lab testing essential for accurate diagnosis.
TSH alone is insufficient for a complete thyroid assessment. A full panel including Free T4, and ideally Free T3 and antibodies, provides a much clearer picture of thyroid health.
| Test | What It Detects | Link |
|---|---|---|
| TSH (Thyroid Stimulating Hormone) | Primary screening test; elevated TSH indicates hypothyroidism, suppressed TSH indicates hyperthyroidism. Optimal range: 1.0-2.5 mIU/L | Lab Tests |
| Free T4 (Thyroxine) | The main thyroid hormone output; low Free T4 with high TSH confirms primary hypothyroidism | Lab Tests |
| Free T3 (Triiodothyronine) | The biologically active form; some patients have poor T4-to-T3 conversion (requires selenium, zinc). Low T3 explains persistent symptoms despite normal TSH | Lab Tests |
| Thyroid Antibodies (TPO, TgAb) | Detect autoimmune thyroiditis (Hashimoto's disease), the most common cause of hypothyroidism. Positive antibodies indicate immune attack on the thyroid | Lab Tests |
Thyroid function depends on specific micronutrients for hormone synthesis and conversion. These supplements address the most common nutritional bottlenecks in thyroid health.
| Supplement | How It Helps | Link |
|---|---|---|
| Ashwagandha (KSM-66) | Adaptogen that modulates TSH levels; clinical trials show significant improvement in subclinical hypothyroidism. Normalizes cortisol, which indirectly supports T4-to-T3 conversion. | Ashwagandha |
| Zinc | Required cofactor for the deiodinase enzyme that converts T4 to active T3. Zinc deficiency impairs thyroid hormone synthesis and peripheral conversion. | Zinc Picolinate |
| Selenium | Essential for Type 2 deiodinase (T4 to T3 conversion) and glutathione peroxidase (protects the thyroid from oxidative damage during hormone production). 200 mcg/day reduces thyroid antibodies in Hashimoto's. | Supplement Stack |
| Vitamin D | Vitamin D deficiency is strongly associated with autoimmune thyroiditis. Supplementation may reduce TPO antibody levels and support immune tolerance. | Vitamin D3 + K2 |
Age-specific TSH thresholds refine subclinical hypothyroidism treatment. A 2025 review in Endocrine Practice consolidated emerging evidence that older adults (age 70+) with subclinical hypothyroidism and TSH below 7.0 mIU/L generally do not benefit from levothyroxine treatment. However, observational data demonstrate increased cardiovascular mortality and stroke risk when TSH reaches 7.0-9.9 mIU/L, and significantly elevated risk of coronary heart disease, heart failure, and death when TSH exceeds 10.0 mIU/L. This age-stratified approach means that for adults under 70, treatment at lower TSH thresholds remains appropriate, while for older adults, a "watch and wait" strategy below TSH 7.0 mIU/L avoids unnecessary medication and its associated risks.
2025 ATA thyroid cancer guidelines update molecular diagnostics. The American Thyroid Association published updated guidelines in 2025 incorporating molecular marker testing (ThyroSeq, Afirma GSC) for thyroid nodule evaluation, reducing unnecessary surgeries for indeterminate cytology results. These molecular classifiers now achieve >95% negative predictive value, meaning a benign result can safely avoid surgery.