What is iodine deficiency and how much iodine do you need every day?
Iodine deficiency is when your body does not have a sufficient supply of the vital trace element iodine. Iodine is essential for the formation of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). These hormones regulate metabolism, growth, brain development and many other bodily functions.
The recommended daily dose of iodine for adults is 200 micrograms. Pregnant women should consume 230 micrograms of iodine per day and breastfeeding mothers as much as 260 micrograms to cover the increased requirement. Children and adolescents also need between 40 and 200 micrograms of iodine per day, depending on their age, for optimal development.
Iodine deficiency symptoms
The symptoms of iodine deficiency can be varied and depend on the severity and duration of the deficiency. The most common signs include
- Enlargement of the thyroid gland (goitre)
- Weight gain
- Fatigue
- Cold intolerance
- Dry skin
- Brittle nails
- Congestion
- Muscle pain
- Joint pain
- Concentration and memory problems
Serious and long-term iodine deficiency can also lead to developmental disorders of the brain in foetuses and infants, as iodine is essential for brain development.
Iodine deficiency symptoms in women
Women are particularly susceptible to iodine deficiency due to hormonal changes. In addition to the general symptoms, they may experience the following complaints:
- Menstrual irregularities
- Fertility problems
- Complications during pregnancy
- Postpartum hypothyroidism
Women who want to have children, pregnant women and breastfeeding mothers in particular should make sure they have an adequate iodine supply and consult their doctor if necessary.
Iodine deficiency causes
The most common cause of iodine deficiency is insufficient dietary intake. In many regions, the iodine content in the soil and drinking water is very low, which means that the food grown there also contains correspondingly little iodine. Particularly at risk of iodine deficiency are:
- Pregnant and breastfeeding women
- Vegans and vegetarians
- People with an unbalanced or unbalanced diet
- People living in iodine-deficient areas
- People who do not use iodised table salt
Certain foods can also impair iodine intake. These include, for example, cabbage vegetables such as broccoli, Brussels sprouts or white cabbage, which contain so-called strumigenic substances. These inhibit the absorption of iodine into the thyroid gland. Nitrate in drinking water and thiocyanates, which are produced by smoking, also interfere with iodine utilisation in the body.
Iodine in food
There are many good sources of iodine, both plant and animal-based. Here is an overview of the 10 most iodine-rich foods (plant and animal) with their average iodine content per 100 g:
Vegan sources of iodine
Vegan iodine sources: Iodine content per 100 g
1. Iodised table salt: 5213 µg
2. Orange juice: 9 µg
3. Spinach (raw): 7 µg
4. Olives: 2 µg
5. Raisins: 2 µg
6. Celery (raw): 2 µg
7. Sweet potatoes (baked): 2 µg
8. Soya milk: 1 µg
9. Prune juice: 1 µg
10. Green leaf lettuce: 1 µg
Animal sources of iodine
Animal sources of iodine: Iodine content per 100 g
1. Lobster (cooked): 185 µg
2. Cod (cooked): 172 µg
3. Swiss cheese: 137 µg
4. Oysters (cooked): 109 µg
5. Parmesan: 82 µg
6. Ricotta: 66 µg
7. Mussels: 66 µg
8. Eggs (cooked): 61 µg
9. Greek yoghurt: 51 µg
10. Mozzarella: 51 µg
However, the iodine content of seafood varies greatly depending on the origin, season and method of preparation. A lot of iodine is lost when grilling and frying. The iodine content of milk and dairy products also depends on how cows are fed and the use of iodine-containing disinfectants.
The most reliable source of iodine is therefore iodised table salt. When shopping, make sure that the salt is labelled "iodised salt" or "iodised". In Germany, 15-25 mg of iodine per kg of salt is added to iodised salt. The use of iodised salt in the household and in the food industry generally ensures that the iodine requirement is well covered.
Preventing iodine deficiency by drinking food
Another way to prevent iodine deficiency is to drink special drinking meals. These astronaut food, such as that offered by the Saturo brand, is characterised by a balanced composition of all essential nutrients, including iodine. Especially for people with an increased iodine requirement, such as pregnant women and breastfeeding mothers, or for people who suffer from limited iodine intake, the regular consumption of such drinkable meals can be a valuable addition to their usual diet. They can help to effectively prevent iodine deficiency and support thyroid and metabolic health in the long term.
Frequently asked questions
What are the signs of iodine deficiency?
Signs of iodine deficiency can include an enlarged thyroid gland (goitre), tiredness, weight gain, dry skin and constipation. In severe cases, an iodine deficiency can lead to an underactive thyroid gland (hypothyroidism).
What should you eat if you have an iodine deficiency?
Iodine-deficient people should eat iodine-rich foods such as sea fish, seafood, dairy products and iodised table salt. Taking iodine tablets or using iodised table salt can also help to compensate for iodine deficiency.
Which organs need iodine?
The thyroid gland is the organ that requires the most iodine, as it produces thyroid hormones that are essential for the body's metabolism, growth and development. Other organs such as the mammary glands, stomach and salivary glands also require iodine to function.
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Sources
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