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THYROID FUNCTION

Zinc

Zn — Element #30

also known as Zinc gluconate, Zinc acetate, Zinc sulfate, Zinc picolinate…

An essential trace mineral involved in over 300 enzymes and more than 1,000 zinc-finger transcription factors. The body has no specialized storage pool, so steady dietary intake matters.

Role in the body Cofactor for ~300 enzymes; structural in ~1,000 transcription factors; essential for immunity, growth, and sensory function

Recommended daily intake
  • Adult Men · 11 mg
  • Adult Women · 8 mg
  • Pregnancy · 11 mg
  • Lactation · 12 mg
Upper intake limit

40 mg/day for adults

Signs of deficiency
  • Impaired immunity, frequent infections
  • Slow wound healing
  • Loss of taste or smell
  • Hair loss
  • Diarrhea
  • Growth delays in children
  • Required for immune cell development, including T-cells and natural killer cells
  • Cofactor for DNA synthesis, cell division, and protein folding
  • Supports wound healing through its role in collagen synthesis
  • Required for normal growth — pregnancy, childhood, adolescence
  • Necessary for the senses of taste and smell
  • Structural to over 1,000 zinc-finger transcription factors

Active in Zn²⁺ ion.

Chronic intake above the upper limit depletes copper, leading to anemia and neurological symptoms
Very high doses (≥150 mg/day) can suppress immune function and lower HDL cholesterol
Reduces absorption of fluoroquinolone and tetracycline antibiotics — separate doses by at least 2 hours
Intranasal zinc gels and swabs have caused permanent loss of smell — not recommended

NIH ODS — Zinc · MedlinePlus — Zinc · Britannica — Zinc

Use with caution
Copper Zinc above 40 mg/day induces intestinal metallothionein, which sequesters copper and can cause copper deficiency over weeks to months.
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The curious few.
50 founding spots left

Know what you're putting in your body.

158 herbs, nutrients, and compounds. What the science says, what tradition knew, and what to watch for. Founding members keep this running.

$60 /year

Founding rate — locked for life. Regular price after launch: $96/year.

  • ✓ Full access to all 158+ entries
  • ✓ Print-ready reference card for every herb
  • ✓ Monthly curated set — 5 herbs, one body system
  • ✓ The Sunday Letter — weekly research digest
  • ✓ Bookmarks synced across devices
  • ✓ Founding rate locked forever
Become a founding member

Cancel any time. No questions asked.