The biological functions of iodine
Iodine's primary function in the body is to support the thyroid gland. This butterfly-shaped organ at the base of the neck uses iodine as a building block for the production of thyroid hormones (T4 and T3). These hormones function as the central regulators of various physiological systems.
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Energy metabolism: Iodine contributes to normal energy-yielding metabolism. It supports the efficient conversion of food into energy, which is essential for daily vitality.
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Cognitive functions: This trace element plays an important role in normal cognitive function. It is involved in concentration, learning ability, and maintaining a clear mind.
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Nervous system: Iodine contributes to the normal functioning of the nervous system, ensuring optimal communication between the brain and the rest of the body.
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Skin condition: In addition to internal processes, iodine is also relevant for maintaining healthy skin.
Natural sources and intake
In Dutch food culture, iodine supply has historically been closely linked to the baking industry. Since the 1940s, iodine has been added to baker's salt to prevent widespread deficiencies.
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Bread: For many people, bread is the most important source of iodine. Four slices of bread prepared with baker's salt can provide more than half of your daily needs.
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Sea fish and seafood: Products such as cod, plaice and shellfish are naturally rich in iodine because they absorb it from seawater.
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Dairy and eggs: Dairy products and eggs also contain iodine, although the concentration depends on the diet the animals received.
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Seaweed and kelp: These are the most concentrated sources of iodine. Due to the very high levels, caution is advised to avoid excessive intake.
Specific target groups and increased needs
Certain life stages and lifestyles require extra attention to iodine status. When regular dietary intake is limited, the balance can be compromised.
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Plant-based lifestyle: Vegans and vegetarians who don't consume seafood, dairy, or eggs are at a higher risk of inadequate intake. If you also choose organic bread (which doesn't always use baker's salt) or homemade bread without iodized salt, caution is advised.
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Pregnancy and breastfeeding: During these periods, iodine requirements are increased. This trace element is not only essential for the mother during this phase, but also plays a crucial role in the early development of the nervous system and the growth of the child.
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Athletes: Intense physical exertion can lead to increased loss of minerals and trace elements through perspiration. Furthermore, an active metabolism places greater demands on thyroid function.
Safety and dosage
Although iodine is essential, there is a margin between adequate intake and excess. The European Food Safety Authority (EFSA) has established a tolerable upper intake of 600 micrograms per day for adults.
Prolonged excess of this limit can affect the thyroid's natural function. This is especially true for individuals with an existing sensitivity to iodine or specific thyroid disorders. Therefore, it is important to always carefully follow the daily dosage when using high-dose supplements, such as kelp tablets.
Quality in support
For those who cannot obtain sufficient iodine from food daily, supplementation offers a reliable method for optimizing their iodine status. When choosing a supplement, the iodine source determines its stability. Potassium iodide-based preparations often offer a precise and consistent dosage, while natural extracts such as kelp can vary in their iodine content.
Summary: Iodine is a cornerstone of healthy physiology. It supports the thyroid, metabolism, and nervous system. By focusing on sources like iodized bread, fish, or high-quality supplements, you'll lay the foundation for your long-term health.
Frequently Asked Questions (FAQ)
How do I know if I'm getting enough iodine? If you eat bread with baker's salt every day and regularly consume fish or dairy products, chances are your intake is adequate. With a completely plant-based diet or if you avoid salt, your intake is often lower.
Is iodine in salt the same as in supplements? Essentially, it's the same substance, often in the form of potassium iodide. However, supplements provide a controlled amount without the need for additional salt consumption.
Can I get too much iodine through food? It's virtually impossible to get too much iodine through a regular diet. Only very frequent consumption of certain types of seaweed can cause intake to exceed the upper limit.
Why is there iodine in bread? This is a historic government decision to protect public health, as Dutch soil and natural food are relatively low in iodine.
