Beyond Salt: What is another source of iodine for your diet?

December 24, 2025 •

4 min read

Iodine is a vital trace mineral the body does not produce, making it an essential component of a healthy diet for producing thyroid hormones. While iodized table salt has long been the primary source for many, a wide variety of natural and fortified foods can also provide this crucial nutrient.

Quick Summary

This article explores excellent dietary sources of iodine beyond iodized salt, including seafood, dairy, eggs, and specific plant-based options. It also covers supplement considerations for meeting daily requirements.

Key Points

Seafood is a top source: Marine fish like cod, as well as shellfish like shrimp and oysters, are naturally rich in iodine from the ocean's waters.
Seaweed content varies: Certain seaweeds, especially kelp, contain extremely high levels of iodine, while others like nori have lower, but still significant, amounts.
Dairy is a common contributor: Milk, yogurt, and cheese are reliable sources of iodine in many diets, though content can vary.
Eggs offer an easy option: A single large egg, particularly the yolk, provides a good boost of iodine, making it a simple addition to meals.
Supplements are an alternative: For those with restricted diets, a multivitamin or targeted supplement can ensure adequate iodine intake, but kelp supplements should be avoided due to unpredictable potency.
Excessive iodine is risky: While deficiency is a concern, consuming too much iodine, especially from high-potency supplements, can also negatively impact thyroid function.

The Importance of Iodine for Your Health

Iodine is a critical component for the proper functioning of the thyroid gland, which uses it to produce essential hormones that regulate the body's metabolism. These hormones are responsible for converting food into energy and managing growth and development. A deficiency can lead to significant health problems, including an enlarged thyroid gland (goiter), hypothyroidism, and potential developmental issues, especially during pregnancy and infancy. Ensuring a consistent intake from varied sources is key to preventing these issues.

High-Iodine Food Sources Beyond Salt

For those limiting salt intake or seeking a broader range of nutrients, several other foods offer excellent sources of iodine.

Seafood: Marine life is one of the richest natural sources of iodine due to the mineral's abundance in the oceans. Cod is a fantastic option, with just a three-ounce serving providing a significant portion of the daily value. Other examples include shrimp, tuna (canned in water), and oysters. The exact iodine content can vary depending on whether the fish is wild-caught or farm-raised.
Seaweed: Often considered a superfood, seaweed is an extremely potent source of iodine, though content varies widely by species. Kelp, nori (used for sushi), and wakame (popular in miso soup) are some of the most common types. However, caution is advised with kelp, as some varieties can contain excessively high levels, potentially leading to thyroid issues if consumed too frequently.
Dairy Products: Milk and dairy products are major contributors of iodine in many Western diets. The amount can fluctuate based on cow feed and sanitation practices in the dairy industry. A cup of milk or yogurt can contain a substantial amount of iodine, making them a reliable daily source. Cheeses, such as cheddar and cottage cheese, also provide iodine.
Eggs: A large egg provides a good dose of iodine, with most of the mineral concentrated in the yolk. This makes them a simple and convenient way to boost your intake.
Certain Vegetables and Fruits: The iodine content in produce is highly dependent on the mineral content of the soil where it is grown. Some options include prunes, lima beans, and potatoes (especially with the skin on).

The Role of Dietary Supplements

For individuals with restricted diets, such as vegans or those with food allergies, supplements can provide a reliable source of iodine.

Iodine is often available as potassium iodide or sodium iodide in multivitamins and specific iodine supplements.
It is vital to choose supplements carefully and avoid those made from kelp, as the iodine concentration can be unreliable and potentially unsafe.
Pregnant and breastfeeding women have higher iodine requirements, and many health organizations recommend supplements during these life stages. It is always best to consult a healthcare provider before starting any new supplement.

Natural Food Sources vs. Supplement Comparison


Feature	Natural Food Sources	Supplements (e.g., Potassium Iodide)
Convenience	Requires intentional meal planning.	Easy to take daily as a pill or liquid.
Nutrient Synergy	Provides a wide range of other vitamins and minerals.	Isolated nutrient; offers no other benefits.
Iodine Content	Highly variable based on soil, source, and processing.	Standardized and reliable dosage per serving.
Risk of Excess	Lower risk of accidental excess (except with high kelp intake).	Higher risk of overconsumption if not monitored by a doctor.
Dietary Restrictions	May be challenging for vegans or those with allergies.	Easily fits most dietary restrictions.
Medical Use	Not suitable for therapeutic purposes or radiation emergencies.	High-dose versions used for specific medical treatments under a physician's care.

Understanding the Risks of Excessive Intake

While iodine is essential, it's possible to get too much, especially through unregulated supplements. High intakes can cause thyroid problems, including both hypothyroidism and hyperthyroidism. Individuals with pre-existing thyroid conditions or those with a history of iodine deficiency should be particularly cautious. The Tolerable Upper Intake Level (UL) for adults is 1,100 mcg per day. For this reason, meeting your needs through a balanced diet is often the preferred approach.

Conclusion

Iodized salt is no longer the only or even the most abundant option for meeting daily iodine needs. A diverse diet incorporating seafood, dairy, eggs, and even some plant-based options can provide this critical mineral. For those with dietary restrictions, fortified foods and supplements offer a reliable alternative, but consultation with a healthcare professional is always recommended to avoid excess intake. By diversifying your iodine sources, you can better support thyroid function and overall health.

For more detailed information on nutrient requirements, consult authoritative resources like the National Institutes of Health's Office of Dietary Supplements.(https://ods.od.nih.gov/factsheets/Iodine-HealthProfessional/)

Frequently Asked Questions

The best food sources of iodine besides iodized salt are seafood (especially saltwater fish like cod and shrimp), seaweed, dairy products, and eggs.

Vegans and vegetarians can find iodine in foods like prunes, lima beans, and potatoes, but the amount can be inconsistent. Fortified plant-based milks and iodine supplements are often recommended to ensure adequate intake.

No, not all salts are iodized. Specialty salts like sea salt, kosher salt, and Himalayan salt typically do not contain added iodine. It is necessary to check the label for the term 'iodized'.

The recommended daily intake of iodine for most adults is 150 micrograms (mcg). Pregnant and breastfeeding women have higher needs, with recommendations of 220 mcg and 290 mcg respectively.

Symptoms of an iodine deficiency can include an enlarged thyroid gland (goiter), weight gain, fatigue, thinning hair, dry skin, and increased sensitivity to cold.

Yes, excessive iodine intake can cause thyroid problems, including both hypothyroidism and hyperthyroidism. High doses, particularly from certain supplements like kelp, should be avoided.

If you have dietary restrictions or are pregnant or breastfeeding, a supplement may be beneficial. However, most adults with a varied diet can meet their needs through food alone. Always consult a healthcare provider before starting a supplement.