How can I increase my iodine naturally through diet?

October 31, 2025 •

4 min read

According to the World Health Organization, roughly 30% of the world's population remains at risk for iodine deficiency. Addressing this vital mineral shortfall is essential for thyroid function and overall well-being, and one of the most effective ways to increase my iodine naturally is through dietary changes.

Quick Summary

Boost your iodine intake by adding naturally rich foods like seaweed, seafood, and dairy to your diet. Incorporate iodized salt for a simple, effective way to support thyroid function and overall health.

Key Points

Rich Seafood Sources: Incorporate fish like cod, tuna, and shellfish such as shrimp and oysters, which are all naturally high in iodine.
Superfood Seaweed: Regularly consume seaweed varieties like kelp, nori, and wakame, which are among the most concentrated natural sources of iodine.
Dairy for Daily Intake: Ensure adequate intake by including dairy products like milk, yogurt, and cheese in your diet.
Consider Iodized Salt: Use iodized table salt for cooking and seasoning as a simple way to meet daily needs, but remember to consume it in moderation.
Balance with Eggs: Add eggs, particularly the yolks, to your meals as they contain a moderate amount of iodine and other essential nutrients.
Know Your Goitrogens: Be mindful that high consumption of cruciferous vegetables and soy can interfere with iodine uptake, though this is only a major concern for those with marginal intake.

Why Is Iodine So Important?

Iodine is a trace element that is vital for producing thyroid hormones, specifically thyroxine (T4) and triiodothyronine (T3). These hormones are essential for regulating metabolism, which affects nearly every cell in the body. Adequate iodine is necessary for proper growth and development, especially for a baby's brain during pregnancy and infancy. A deficiency can lead to a variety of health issues, including an enlarged thyroid gland (goiter), hypothyroidism, and developmental problems in children. While iodized salt has helped reduce deficiency rates significantly in many parts of the world, relying solely on it can be inconsistent, making dietary sources crucial.

The Top Natural Food Sources of Iodine

Incorporating a variety of foods naturally rich in iodine is the most straightforward way to ensure you meet your daily needs. The ocean is the largest natural source of iodine, making seafood and seaweed exceptional choices.

Seaweed and Seafood

Seaweed is arguably the most concentrated natural source of iodine. Different types offer varying amounts, so it's best to consume them in moderation to avoid excessive intake.

Kelp: An excellent source, often available in dried form.
Nori: The seaweed used in sushi, containing a healthy dose of iodine.
Wakame: A common addition to miso soup, also high in this mineral.

For those who prefer a fishy flavor, numerous seafood options can help boost iodine levels without relying on seaweed:

Cod: A three-ounce serving of baked cod can provide a significant portion of the daily recommended intake.
Tuna: Canned tuna, particularly in water, is a convenient and good source of iodine.
Shrimp: These popular crustaceans are a reliable source and can be added to many dishes.
Oysters: Cooked oysters are another shellfish option packed with iodine.

Dairy Products

Dairy is a significant contributor to iodine intake in many diets, mainly because the iodine content of animal feed and the use of iodine-containing disinfectants in the milking process.

Milk: A simple cup of non-fat milk can supply a good amount of your daily iodine.
Yogurt: Greek and regular yogurt are both excellent sources, perfect for a breakfast or snack.
Cheese: Cheeses like cheddar and cottage cheese also contain iodine, though typically in lower amounts than milk or yogurt.

Eggs and Other Animal Products

Eggs, particularly the yolks, contain a moderate amount of iodine, making them a great addition to breakfast. Meat products like beef liver and chicken also contribute, but generally contain less iodine than seafood or dairy.

Vegetables and Fruits

While the iodine content in plant-based foods can be inconsistent due to the mineral's presence in the soil, some produce can contribute to your overall intake.

Potatoes: Baked potatoes, eaten with the skin, contain some iodine.
Lima Beans: A half-cup serving of these beans can offer a small but beneficial amount of iodine.
Prunes: Dried prunes provide a source of iodine along with other nutrients.

Dietary Considerations and Goitrogens

Certain compounds known as goitrogens can interfere with the thyroid's ability to use iodine, potentially exacerbating a deficiency. These are found in cruciferous vegetables such as broccoli, cauliflower, and cabbage, and in some soy products. For most people with adequate iodine intake, eating these foods is not an issue. However, those with a marginal intake should be mindful, though cooking these vegetables typically reduces their goitrogenic effects. Vegans and vegetarians who do not consume iodized salt may need to pay closer attention to their iodine intake to ensure it is sufficient.

Comparison of Iodine Sources


Food Source	Serving Size	Approximate Iodine (mcg)	Notes
Seaweed (Nori)	2 tbsp flakes (5g)	~116	Varies significantly by species and processing.
Cod (Baked)	3 ounces	~146	Excellent source, provides almost a full day's needs.
Greek Yogurt (Plain)	¾ cup	~87	Good dairy option for breakfast or snacks.
Nonfat Milk	1 cup	~84	Widely available and reliable source.
Iodized Salt	¼ teaspoon	~78	A primary source for many, but moderation is key.
Hard-Boiled Egg	1 large	~31	Easy to incorporate into meals.
Shrimp (Cooked)	3 ounces	~13	A low-fat protein source.

Conclusion

To increase your iodine naturally, the most effective strategy is a balanced diet rich in seafood, seaweed, and dairy products. Using iodized salt in moderation for cooking is also a simple and reliable method. While plant-based foods can contribute, they are generally less reliable due to soil content variability. For individuals with restricted diets, such as vegans, focusing on consistently fortified foods, like some plant-based milks, or consulting a healthcare professional about supplementation is a prudent approach. Ultimately, a varied and thoughtful diet is the best defense against iodine deficiency and supports optimal thyroid function. Further detailed nutritional information can be found on authoritative sites such as the NIH Office of Dietary Supplements.

Frequently Asked Questions

Seaweed, especially kelp, is one of the richest natural dietary sources of iodine. Other top sources include various types of fish and shellfish.

No, only table salt that is specifically labeled 'iodized' contains added iodine. Many other types of salt, such as kosher, Himalayan, and sea salt, do not contain iodine unless stated otherwise.

Most adults need about 150 micrograms (mcg) of iodine per day. This requirement increases for pregnant and breastfeeding women.

While uncommon from food alone, excessive iodine intake, particularly from supplements, can lead to hyperthyroidism, inflammation of the thyroid, and, in rare cases, can trigger hypothyroidism.

Yes, vegans and those who avoid seafood and dairy are at a higher risk of iodine deficiency, as these are primary dietary sources. They may need to consider fortified foods or supplements.

Yes, cooking or steaming cruciferous vegetables and other goitrogenic foods can reduce their ability to interfere with iodine uptake.

Iodine deficiency is typically diagnosed by a healthcare professional, often through a urine or blood test. Symptoms like a goiter, fatigue, or unexplained weight gain may also suggest a deficiency.