Iodine
Description
Iodine is a crucial trace mineral that plays a central role in human health, primarily through its involvement in the synthesis of thyroid hormones, triiodothyronine (T3) and thyroxine (T4). These hormones are fundamental regulators of metabolic processes throughout the body, impacting energy production, body temperature, and the proper functioning of virtually all organs. Adequate iodine intake is therefore indispensable for maintaining metabolic balance. Beyond its well-known role in metabolism, iodine is critical for normal growth and development, especially of the brain and nervous system, particularly during fetal development and early childhood. It supports cognitive function, nerve transmission, and energy levels, contributing to overall vitality and mental acuity. Deficiencies can lead to a range of issues, from impaired cognitive function to more severe conditions like goiter and hypothyroidism. Maintaining optimal iodine levels is also important for reproductive health and a healthy immune system. Given its widespread influence on bodily functions, ensuring sufficient intake through diet or supplementation is a key aspect of preventive health, supporting not only thyroid health but also broader physiological well-being.
Sources
Seaweed (kelp, nori, kombu)Cod, tuna, and other fishShrimp and other seafoodDairy products (milk, yogurt, cheese)EggsIodized saltSome fruits and vegetables, depending on soil content
Cheapest Iodine supplements
Best Iodine supplements
Value Iodine supplements
Timing & Intake
AnytimeWith foodTake with Food to minimize potential stomach upset.
Iodine can be taken at any time of day, preferably with a meal for better tolerance.
Daily Intake
RDA (Men)150 mcg
RDA (Women)150 mcg
RDI150 mcg
Optimal Dosage
Minimum150 mcg
Maximum300 mcg
Safety & Toxicity
Upper Limit (UL)1100 mcg
Toxicity Threshold2000 mcg
Toxicity EffectThyroid dysfunction
Goals
Energy
Impact
Highest effect
The thyroid gland cannot produce T3 and T4 hormones without adequate iodine. These hormones control the speed of cellular processes throughout the body. An iodine deficiency can lead to hypothyroidism, a condition whose primary symptoms include severe fatigue, weight gain, and low energy.
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Weight Loss
Impact
Highest effect
The thyroid gland cannot produce its hormones (T3 and T4) without adequate iodine. A deficiency, even a mild one, directly leads to a sluggish metabolism, making it significantly harder to lose weight. Ensuring sufficient intake is foundational for an efficient metabolism.
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Hair Health
Impact
Situational effect
The thyroid gland requires iodine to produce hormones T3 and T4, which directly regulate the hair growth cycle. A deficiency can lead to hypothyroidism, a well-established cause of diffuse hair loss. Supplementation is critical for individuals with deficiency or related thyroid issues.
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Mental Focus
Impact
Situational effect
The thyroid gland controls the body's metabolic rate, and the brain is a highly metabolic organ. Iodine deficiency leads to hypothyroidism, a common cause of severe brain fog, poor memory, and an inability to concentrate. Ensuring adequate iodine is foundational for mental energy and clarity.
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Metabolism Boost
Impact
Situational effect
Typical dose:150–300 mcg
The thyroid gland cannot produce its hormones without adequate iodine. In cases of insufficiency, thyroid function slows, directly reducing metabolic rate. For individuals with low iodine intake, this supplement is crucial for restoring normal metabolic function.
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Interactions
Positive Interactions
Selenium
Selenium is crucial for the activity of enzymes involved in thyroid hormone metabolism and conversion, protecting the thyroid gland from oxidative damage that can result from iodine metabolism.
Iron
Iron is necessary for the proper synthesis of thyroid hormones; iron deficiency can impair thyroid hormone production even with adequate iodine.
Vitamin A
Vitamin A status can influence thyroid hormone metabolism and the body's response to iodine, supporting overall thyroid health.
Zinc
Zinc is essential for the synthesis of thyroid hormones and the conversion of T4 to the more active T3 hormone.
Recommended products
Value 
Complete Multivitamin Adults 50+
Equate
Iodine: 150 mcg
This multivitamin for adults 50+ offers a foundational blend of essential vitamins, minerals, and key carotenoids like Lutein and Lycopene, supporting general health, bone density, and vision at a very accessible price.
Value 
Sentry Senior
21st Century
Iodine: 150 mcg
A comprehensive and affordable daily multivitamin for seniors, providing essential vitamins, minerals, plus Lutein and Lycopene for broad health and vision support.
Best 
Potassium Plus Iodine
NOW
Iodine: 225 mcg
This supplement combines elemental potassium and iodine in a convenient tablet form, aiming to support general metabolic function and electrolyte balance.
Best 
Iodine 1500 mcg
Dr. Mercola
Iodine: 1500 mcg
A high-potency iodine capsule delivering a substantial daily amount of potassium iodide for targeted supplementation.
Value 
Icelandic Kelp
NaturesPlus
Iodine: 150 mcg
NaturesPlus Icelandic Kelp provides 150mcg of iodine from natural kelp in tablet form, serving as an economical option for daily thyroid and metabolic support.
Value 
Sentry Adults
21st Century
Iodine: 150 mcg
A very affordable and broad-spectrum daily multivitamin and multimineral for adults, offering foundational nutritional support for overall well-being.
Best 
Kelp Whole Thallus 600 mg
Nature's Way
Iodine: 270 mcg
This kelp supplement provides natural iodine for thyroid support and general metabolic health, offered in a convenient 100-capsule bottle.
Best 
Iodine 1500 mcg
Dr. Mercola
Iodine: 1500 mcg
A larger, more economical bottle of Dr. Mercola's high-potency potassium iodide capsules for sustained, targeted iodine support.
Best 
Kelp
Oregon's Wild Harvest
Iodine: 400 mcg
A high-potency organic kelp capsule offering 400mcg iodine with substantial kelp biomass for comprehensive natural support.
Value 
Kelp 325 mcg
Nutricost
Iodine: 325 mcg
An economical kelp supplement providing a robust 325mcg iodine dose per tablet for daily support.
Value 
Iodine+
Codeage
Iodine: 250 mcg
A very economical liquid nascent iodine supplement, providing a moderate daily dose with excellent value.
Best 
Thyro-Max Support
Country Life
Iodine: 450 mcg
Thyro-Max Support combines iodine, L-tyrosine, B vitamins, and essential minerals to help bolster metabolic function, energy levels, and overall vitality.
Best 
Bladderwrack Whole Thallus 580 mg
Nature's Way
Iodine: 232 mcg
A capsule supplement providing iodine from natural bladderwrack, a traditional sea vegetable, for daily intake.
Value 
Kelp
Swanson
Iodine: 225 mcg
An extremely high-potency kelp product with a stated iodine content of over 56mg, posing serious safety concerns for general use.
Value 
Prenatal Multivitamin/Multimineral with Folate
Spring Valley
Iodine: 150 mcg
<p>This prenatal multivitamin delivers a key set of vitamins and minerals, including a good amount of folate and iron, tailored to support nutritional needs during pregnancy at a very affordable price.</p>
Best 
Detoxadine
Global Healing
Iodine: 1950 mcg
A high-potency liquid nascent iodine supplement, offering 1950mcg per serving for advanced support.
Best 
XenoStat
Premier Research Labs
Iodine: 300 mcg
XenoStat offers 300mcg of iodine in a capsule, combined with undisclosed "Botanica Detox" and "Botanica Support" proprietary blends, aimed at general wellness.
Value 
Kelp
NOW
Iodine: 325 mcg
This NOW Kelp supplement delivers a significant 325mcg of iodine from organic kelp in an economical capsule form, offering targeted support for thyroid function and overall metabolic health.
Value 
North Atlantic Kelp
Solgar
Iodine: 200 mcg
A reliable tablet delivering iodine from North Atlantic kelp, offering a natural source for daily thyroid support.
Best 
Sea-Iodine 1000 mcg
Life Extension
Iodine: 1000 mcg
A highly popular high-dose iodine capsule, likely sourced from sea vegetables, offering significant daily support.
Product stats
Price per product
Average$30.43
Median$24.99
Price per serving
Average$0.75
Median$0.54
Price per 100 mcg
Average$1.03
Median$0.47
Price distribution
Price per serving distribution
Price per 100 mcg
Reference amount: 100 mcg
Forms
Paired ingredients
Ingredient forms
Potassium Iodide (455) 85
Potassium Iodide (KI) is a readily absorbed, pharmaceutical-grade form of iodine. It is widely recognized for its efficacy in preventing iodine deficiency and for its critical role in blocking the uptake of radioactive iodine by the thyroid gland during nuclear emergencies. Its precise iodine content allows for accurate and consistent dosing.
Pros
- Highly bioavailable and well-absorbed
- Provides precise and consistent dosing
- Effective for preventing iodine deficiency
- Medically recognized for thyroid protection against radioactive iodine
Cons
- Synthetic form, not a whole-food source
- Potential for gastrointestinal upset in some individuals
- Risk of overdose if not monitored carefully
Per product
Avg$30.97
Med$24.32
Per serving
Avg$0.79
Med$0.53
Per 100 mcg
Avg$0.88
Med$0.42
Price distribution
Kelp (149) 78
Kelp is a large brown algae naturally rich in iodine, along with a spectrum of other essential minerals, vitamins, and antioxidants. As a whole-food source, it delivers iodine within a natural matrix, which is preferred by some over isolated forms. However, the iodine content can be highly variable depending on the kelp species, harvest location, and processing methods.
Pros
- Natural, whole-food source of iodine
- Provides additional trace minerals, vitamins, and phytonutrients
- Generally well-tolerated by most individuals
Cons
- Highly variable iodine content, making consistent dosing challenging
- Potential for heavy metal contamination if sourced from polluted waters
- Can be high in sodium
Per product
Avg$27.44
Med$24.95
Per serving
Avg$0.67
Med$0.48
Per 100 mcg
Avg$0.91
Med$0.35
Price distribution
fermented Iodine Glycinate (30) 88
Iodine Glycinate is a chelated form where iodine is molecularly bound to glycine, an amino acid, to potentially enhance absorption and reduce digestive upset. The fermentation process is intended to further improve nutrient bioavailability and may introduce beneficial postbiotic compounds. This form aims for gentle, efficient absorption, offering a modern approach to iodine supplementation.
Pros
- Potentially superior bioavailability due to chelation and fermentation
- Designed to be gentler on the stomach, reducing irritation
- Stable and easily dosed form
Cons
- Newer form with less extensive long-term research compared to traditional forms
- May be higher in cost than inorganic iodine sources
Per product
Avg$38.72
Med$36.29
Per serving
Avg$0.68
Med$0.60
Per 100 mcg
Avg$0.74
Med$0.59
Price distribution
organic Kelp (14) 83
Organic Kelp is harvested or cultivated under strict organic guidelines, meaning it is typically free from synthetic pesticides, fertilizers, and potentially from certain environmental pollutants, depending on the certification body and source. This provides an assurance of purity and sustainable practices. Like other kelp forms, it offers iodine along with other beneficial nutrients in a whole-food matrix.
Pros
- Natural, whole-food source of iodine
- Certified organic ensures purity and adherence to sustainable practices
- Provides additional trace minerals and phytonutrients
Cons
- Iodine content can still vary, requiring careful consideration of dosage
- May have higher sodium content
- Generally more expensive than non-organic kelp
Per product
Avg$17.80
Med$17.09
Per serving
Avg$0.36
Med$0.31
Per 10 mcg
Avg$0.04
Med$0.03
Price distribution
North Atlantic Kelp (13) 82
North Atlantic Kelp emphasizes the geographic origin of the kelp, often indicating a higher standard of purity and nutrient density due to the presumed cleaner waters and specific marine environment of the North Atlantic. Like other forms of kelp, it provides iodine along with a broad spectrum of other essential minerals and vitamins in its natural food matrix.
Pros
- Natural, whole-food source of iodine
- Specific sourcing from North Atlantic suggests higher purity and quality control
- Provides additional trace minerals and phytonutrients
Cons
- Iodine content can still vary, though potentially more consistent than general kelp
- May have higher sodium content
- Specific sourcing may lead to a higher product cost
Per product
Avg$39.34
Med$35.25
Per serving
Avg$1.17
Med$0.78
Per 100 mcg
Avg$0.78
Med$0.52
Price distribution
S. cerevisiae (11) 89
Saccharomyces cerevisiae, commonly known as brewer's or baker's yeast, is utilized to organically bind iodine, creating a food-form mineral. This process results in an iodine complex that is often well-absorbed and tolerated by the body, potentially reducing gastrointestinal issues associated with inorganic forms. The yeast cells naturally incorporate the iodine, enhancing its bioavailability and providing additional nutritional benefits from the yeast matrix.
Pros
- Highly bioavailable due to its food-bound nature
- Gentle on the digestive system, reducing potential irritation
- Provides additional nutrients from the yeast matrix
- Precise dosing possible with standardized products
Cons
- Not suitable for individuals with yeast allergies or sensitivities
- Less common than inorganic forms, potentially higher cost
- Iodine content needs to be carefully standardized by the manufacturer
Per product
Avg$44.93
Med$38.24
Per serving
Avg$0.88
Med$1.02
Per 100 mcg
Avg$0.67
Med$0.70
Price distribution
wild, hand-harvested Kelp (9) 87
This form of kelp emphasizes both its natural origin (wild) and the careful, sustainable collection method (hand-harvested). Wild harvesting suggests a pristine marine environment, while hand-harvesting often implies a more selective approach, potentially yielding higher quality and cleaner kelp with fewer contaminants than mechanically harvested varieties. It offers iodine as part of a rich, natural nutrient profile.
Pros
- Natural, whole-food source with potentially superior purity and nutrient profile
- Emphasizes sustainable and environmentally responsible harvesting practices
- Provides additional trace minerals, vitamins, and phytonutrients
Cons
- Iodine content can still vary, requiring careful consideration of dosage
- Higher cost due to labor-intensive and selective harvesting methods
- Availability may be more limited compared to mass-produced kelp
Per product
Avg$34.45
Med$36.95
Per serving
Avg$0.77
Med$0.66
Per 100 mcg
Avg$0.53
Med$0.39
Price distribution
organic Sea Kelp (8) 78
Kelp is a large brown algae naturally rich in iodine, along with a spectrum of other essential minerals, vitamins, and antioxidants. As a whole-food source, it delivers iodine within a natural matrix, which is preferred by some over isolated forms. However, the iodine content can be highly variable depending on the kelp species, harvest location, and processing methods.
Pros
- Natural, whole-food source of iodine
- Provides additional trace minerals, vitamins, and phytonutrients
- Generally well-tolerated by most individuals
Cons
- Highly variable iodine content, making consistent dosing challenging
- Potential for heavy metal contamination if sourced from polluted waters
- Can be high in sodium
Per product
Avg$41.62
Med$34.29
Per serving
Avg$1.04
Med$1.08
Per 10 mcg
Avg$0.14
Med$0.15
Price distribution
Iodine Glycinate (7) 88
Iodine Glycinate is a mineral chelate where iodine is chemically bonded to the amino acid glycine. This chelation helps protect the iodine from adverse interactions in the digestive tract, potentially leading to better absorption and reduced stomach upset compared to some inorganic forms. It is designed for optimal absorption and gentle delivery, making it a favorable option for sensitive individuals.
Pros
- Improved bioavailability due to chelation with glycine
- Designed to be gentler on the stomach, reducing irritation
- Stable form with precise dosing capability
Cons
- Generally higher cost than simpler inorganic forms of iodine
- Less extensive long-term research compared to highly traditional forms like Potassium Iodide
Per product
Avg$38.23
Med$36.29
Per serving
Avg$0.80
Med$0.81
Per 10 mcg
Avg$0.10
Med$0.08
Price distribution
Atlantic Kelp (6) 78
Kelp is a large brown algae naturally rich in iodine, along with a spectrum of other essential minerals, vitamins, and antioxidants. As a whole-food source, it delivers iodine within a natural matrix, which is preferred by some over isolated forms. However, the iodine content can be highly variable depending on the kelp species, harvest location, and processing methods.
Pros
- Natural, whole-food source of iodine
- Provides additional trace minerals, vitamins, and phytonutrients
- Generally well-tolerated by most individuals
Cons
- Highly variable iodine content, making consistent dosing challenging
- Potential for heavy metal contamination if sourced from polluted waters
- Can be high in sodium
Per product
Avg$31.67
Med$32.36
Per serving
Avg$0.92
Med$0.71
Per 10 mcg
Avg$0.23
Med$0.22
Price distribution