What works, what does not, and what is dangerous. Reviewed by theAvelor Research Team.
Effective Dose
200mcg/day selenomethionine
Reduces TPO antibody levels in Hashimoto's thyroiditis over 3-6 months.
PMID: 17717033Effective Dose
1000-4000 IU/day to target 40-60 ng/mL
Deficiency common in autoimmune thyroid disease. Correcting it supports immune modulation.
PMID: 28359097Effective Dose
25-65mg elemental, separate from levothyroxine
Low iron impairs thyroid hormone synthesis and conversion. Test ferritin.
PMID: 20581817Effective Dose
150mcg daily — NO more
Required for thyroid hormone synthesis. Megadosing is harmful. Use only if deficient.
PMID: 20167667Effective Dose
15-30mg with copper balance
Low zinc reduces T4-to-T3 conversion. Only supplement if blood zinc is low.
PMID: 11322635"Thyroid Support" Iodine Blends
Most contain 1000-5000x the RDA. Triggers hypothyroidism or Hashimoto's flare in susceptible people.
Ashwagandha for Hypothyroid
Can cause thyrotoxicosis. Avoid with levothyroxine.
Kelp/Bladderwrack Megadoses
Variable, sometimes extreme iodine content. Dangerous without lab monitoring.
Generic "Thyroid Reset" Blends
Usually combine iodine + ashwagandha + tyrosine — the worst possible stack for most people.
Causes FALSE low TSH and FALSE high T4. FDA warning. Can trigger unnecessary med changes.
Worsens both conditions. Can cause iodine-induced hypothyroidism.
Thyrotoxicosis risk. Additive effect.
Reduced levothyroxine absorption. Must separate by 4+ hours.
Reduces absorption. Separate by 4 hours.