Condition
Thyroid Health
The thyroid is a small gland in the neck that makes hormones controlling metabolism, energy and growth. Iodine and selenium have the strongest evidence, since iodine is built into thyroid hormones and selenium helps convert T4 into active T3, and in one small trial of healthy men, blood T3 went down with iodide supplements. That finding rests on just 32 men, so the evidence is limited and may not apply to people with thyroid problems.
Sources: PMID 3139337
- Supplements studied
- 2
- Graded outcomes
- 2
- Trials
- 2
- People studied
- 42
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Serum T3 Small Decrease | Improves (the measure goes down) | Small effect | 1 study | 32 people | ||
Studies that measured serum t3 | ||||||
| Thyroid-Stimulating Hormone | Improves (the measure goes up) | 3 studies | 32 people | |||
Studies that measured thyroid-stimulating hormone | ||||||
| Serum T4 | Improves (the measure goes up) | 32 people | ||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Free Testosterone Small Increase | Improves (the measure goes up) | Small effect | 10 people | |||
| Testosterone | Improves (the measure goes up) | 3 studies | 10 people | |||
Studies that measured testosterone
| ||||||
| Serum T3 | Improves (the measure goes up) | 10 people | ||||
| Serum T4 | Improves (the measure goes up) | 10 people | ||||
Key findings
- Serum T3Improves (the measure goes down)
- Free TestosteroneImproves (the measure goes up)
The General Thyroid Health Support protocol
2 primary supplements · 4 supporting supplements
Studies cited
85 studies from PubMed
- Breast-milk iodine concentration declines over the first 6 mo postpartum in iodine-deficient women
- Effect of low dose iodide supplementation on thyroid function in potentially susceptible subjects: are dietary iodide levels in Britain acceptable
- The effect of small increases in dietary iodine on thyroid function in euthyroid subjects
- Effects of low dose oral iodide supplementation on thyroid function in normal men
- Iodine intakes of 100-300 μg/d do not modify thyroid function and have modest anti-inflammatory effects
- Iodine supply and thyroid function in women with gestational diabetes mellitus: a cohort study.
- Effects of folic acid and folic acid plus zinc supplements on the sperm characteristics and pregnancy outcomes of infertile men: A systematic review and meta-analysis.
- A systematic review and meta-analysis examining the role of zinc supplementation in ameliorating physical and psychological manifestations of premenstrual syndrome in young females.
- Effect of Zinc Supplementation on Physical and Psychological Symptoms, Biomarkers of Inflammation, Oxidative Stress, and Brain-Derived Neurotrophic Factor in Young Women with Premenstrual Syndrome: a Randomized, Double-Blind, Placebo-Controlled Trial
- Effect of zinc sulfate supplementation on premenstrual syndrome and health-related quality of life: Clinical randomized controlled trial
- Effect of zinc supplementation on markers of insulin resistance, oxidative stress, and inflammation among prepubescent children with metabolic syndrome
- Effect of zinc supplementation on insulin resistance and components of the metabolic syndrome in prepubertal obese children
- Effect of zinc supplementation on antioxidant activity in young wrestlers
- Randomized, double-blind trial of 220 mg zinc sulfate twice daily in the treatment of rosacea
- Oral zinc sulfate in the treatment of rosacea: a double-blind, placebo-controlled study
- Prophylaxis and treatment of rhinovirus colds with zinc gluconate lozenges
- Two randomized controlled trials of zinc gluconate lozenge therapy of experimentally induced rhinovirus colds
- Zinc gluconate and the common cold: a controlled clinical study
- Duration and severity of symptoms and levels of plasma interleukin-1 receptor antagonist, soluble tumor necrosis factor receptor, and adhesion molecules in patients with common cold treated with zinc acetate
- Zinc acetate lozenges for the treatment of the common cold: a randomised controlled trial
- Zinc gluconate lozenges for treating the common cold. A randomized, double-blind, placebo-controlled study
- Effect of treatment with zinc gluconate or zinc acetate on experimental and natural colds
- Reduction in duration of common colds by zinc gluconate lozenges in a double-blind study
- Zinc gluconate lozenges for common cold. A double-blind clinical trial
- Duration of symptoms and plasma cytokine levels in patients with the common cold treated with zinc acetate. A randomized, double-blind, placebo-controlled trial
- Zinc supplementation decreases incidence of infections in the elderly: effect of zinc on generation of cytokines and oxidative stress
- Zinc sulfate in the prevention of radiation-induced oropharyngeal mucositis: a prospective, placebo-controlled, randomized study
- Zinc increases the effects of essential amino acids-whey protein supplements in frail elderly
- Effects of zinc supplementation on efficacy of antidepressant therapy, inflammatory cytokines, and brain-derived neurotrophic factor in patients with major depression
- Zinc monotherapy increases serum brain-derived neurotrophic factor (BDNF) levels and decreases depressive symptoms in overweight or obese subjects: A double-blind, randomized, placebo-controlled trial
- Zinc supplementation combined with antidepressant drugs for treatment of patients with depression: a systematic review and meta-analysis
- Effect of zinc supplementation on mood states in young women: a pilot study
- Zinc supplementation augments efficacy of imipramine in treatment resistant patients: a double blind, placebo-controlled study
- Zinc supplementation improved cognitive performance and taste acuity in Indian adolescent girls
- Short-term zinc supplementation in women with non-insulin-dependent diabetes mellitus: effects on plasma 5'-nucleotidase activities, insulin-like growth factor I concentrations, and lipoprotein oxidation rates in vitro
- Effect of zinc supplementation in the management of type 2 diabetes: A grading of recommendations assessment, development, and evaluation-assessed, dose-response meta-analysis of randomized controlled trials.
- Effect of zinc supplementation on glycemic biomarkers: an umbrella of interventional meta-analyses.
- Zinc decreases C-reactive protein, lipid peroxidation, and inflammatory cytokines in elderly subjects: a potential implication of zinc as an atheroprotective agent
- Oral zinc supplementation does not improve oxidative stress or vascular function in patients with type 2 diabetes with normal zinc levels
- New insights about iron bioavailability inhibition by zinc
- Effect of fatiguing bicycle exercise on thyroid hormone and testosterone levels in sedentary males supplemented with oral zinc
- Zinc may regulate serum leptin concentrations in humans
- Oral zinc sulphate in the treatment of recalcitrant viral warts: randomized placebo-controlled clinical trial
- Topical zinc sulphate solution for treatment of viral warts
- The efficacy of zinc supplementation on outcome of children with severe pneumonia. A randomized double-blind placebo-controlled clinical trial
- Efficacy of zinc given as an adjunct in the treatment of severe and very severe pneumonia in hospitalized children 2-24 mo of age: a randomized, double-blind, placebo-controlled trial
- Two weeks of zinc administration to Nepalese children with pneumonia does not reduce the incidence of pneumonia or diarrhea during the next six months
- Role of zinc in severe pneumonia: a randomized double bind placebo controlled study
- A randomized controlled trial of oral zinc in acute pneumonia in children aged between 2 months to 5 years
- Zinc adjunct therapy reduces case fatality in severe childhood pneumonia: a randomized double blind placebo-controlled trial
- A randomized controlled trial of the effect of zinc as adjuvant therapy in children 2-35 mo of age with severe or nonsevere pneumonia in Bhaktapur, Nepal
- A randomized controlled trial of zinc as adjuvant therapy for severe pneumonia in young children
- Normalization of zinc intake enhances neurological retrieval of patients suffering from ischemic strokes
- The role of zinc in the treatment of tinnitus
- The effect of exhaustion exercise on thyroid hormones and testosterone levels of elite athletes receiving oral zinc
- Multicenter randomized comparative double-blind controlled clinical trial of the safety and efficacy of zinc gluconate versus minocycline hydrochloride in the treatment of inflammatory acne vulgaris
- Oral zinc sulphate therapy in acne vulgaris: a double-blind trial
- Low doses of zinc gluconate for inflammatory acne
- Oral zinc in acne vulgaris: a clinical and methodological study
- Failure of zinc gluconate in treatment of acute upper respiratory tract infections
- Elevated intakes of zinc in infant formulas don not interfere with iron absorption in premature infants
- Zinc supplementation for improving pregnancy and infant outcome.
- Zinc supplementation for the promotion of growth and prevention of infections in infants less than six months of age.
- Effect of enteral zinc supplementation on growth and neurodevelopment of preterm infants: a systematic review and meta-analysis
- Effects of low dose zinc supplementation on biochemical markers in non-alcoholic cirrhosis: a randomized clinical trial
- The effect of zinc sulfate in the prevention of high-dose chemotherapy-induced mucositis: a double-blind, randomized, placebo-controlled study
- Treatment of localized psoriasis with a topical formulation of zinc pyrithione
- Supplemented zinc does not alter mood in healthy older European adults--a randomised placebo-controlled trial: the Zenith study
- Impact of oral zinc therapy on the level of sex hormones in male patients on hemodialysis
- Effects of zinc supplementation on serum zinc and C-reactive protein concentrations in hemodialysis patients
- Zinc for attention-deficit/hyperactivity disorder: placebo-controlled double-blind pilot trial alone and combined with amphetamine
- A randomized double-blind, placebo-controlled trial of zinc sulfate supplementation for alleviation of radiation-induced oral mucositis and pharyngitis in head and neck cancer patients
- Evaluation of the efficacy of zinc sulfate in the prevention of chemotherapy-induced mucositis: a double-blind randomized clinical trial
- Evaluation of oral zinc sulfate effect on obsessive-compulsive disorder: a randomized placebo-controlled clinical trial
- A randomized, placebo controlled trial of oral zinc for chemotherapy-related taste and smell disorders
- The effect of systemic zinc supplementation on oral health in low socioeconomic level children
- Zinc sulfate for relief of pruritus in patients on maintenance hemodialysis
- Efficacy of exogenous oral zinc in treatment of patients with carbonic anhydrase VI deficiency
- Zinc inhibits nonheme iron bioavailability in humans
- Effect of increasing concentrations of zinc on the absorption of iron from iron-fortified milk
- Oral zinc for treating diarrhoea in children.
- Oral zinc supplementation for the treatment of acute diarrhea in children: a systematic review and meta-analysis.
- Zinc supplementation for treating diarrhea in children: a systematic review and meta-analysis.
- Zinc supplementation for acute and persistent watery diarrhoea in children: A systematic review and meta-analysis.
- Zinc for the prevention or treatment of acute viral respiratory tract infections in adults: a rapid systematic review and meta-analysis of randomised controlled trials