Thyroid Month: Why you should be thinking about seaweed

Iodine and thyroid function: what you need to know

January is #thyroidawarenessmonth and a great opportunity to discuss #iodine and #thyroid function. This topic covers one of the most common queries in relation to eating seaweed – how does iodine affect thyroid function? What happens if you eat too much iodine? Is iodine bad for you?

In fact, it’s thought that hypothyroidism (an underactive thyroid) is more common than hyperthyroidism (an overactive thyroid) and that around 5% of Europe’s population may suffer from the symptoms caused by a lack of iodine. This article will dive into iodine and thyroid function and #seaweed's role in maintaining a healthy hormone balance.

What is the thyroid gland?

The thyroid gland (glandula thyreoidea) is a small, butterfly-shaped gland at the base of the neck. It produces the hormones thyroxine (T4) and triiodothyronine (T3). These hormones stimulate and regulate cell metabolism – the speed at which our bodily functions are performed. These include:

• Transformation of food into energy
• Absorption of oxygen
• Breakdown and uptake of glucose
• Breakdown of fats and increase of free fatty acids
• Lowering cholesterol levels
• Regulation of the rate and strength of the heartbeat
• Fetal and postnatal brain development
• Regulation of sexual functions like libido and menstrual cycles
• Maintenance of regular sleep patterns and focus

Iodine and thyroid function

Iodine is one of the main building blocks of T3 and T4 – the thyroid gland requires it to do its job. Our bodies do not produce iodine naturally, so it’s important that we get enough of it in our diets. Iodine is absorbed into our bloodstream via the bowel as part of digestion. It’s then carried to the thyroid gland, where it is used to create thyroid hormones.

Iodine is found in many food groups, mostly in animal proteins (milk, cheese, eggs, yogurt, fish, shellfish, beef liver, and chicken), seaweed, and kelp. This is important for those following a plant-based diet, especially expectant mothers and young children. Before the iodization of table salt around 100 years ago, the instances of goiter (a swollen thyroid gland) were concentrated in mountainous, inland regions, which suggests that people living and eating off the coasts and surrounding areas received adequate iodine through their diets:

Prior to the 1920s, endemic iodine deficiency was prevalent in the Great Lakes, Appalachians, and Northwestern regions of the U.S., a geographic area known as the “goiter belt”, where 26%–70% of children had clinically apparent goiter.

In the 1920s, a program of salt iodization began, first in Switzerland and shortly thereafter in the USA:

In 1922, Swiss physician/surgeon Hans Eggenberger campaigned to improve iodine nutrition, petitioning the government to iodize salt, and working with his family to iodize and distribute it in his region. The positive results led to Switzerland’s modern, sustainable salt iodization program today. That in turn led in the 1990s to the creating of the Universal Salt Iodization campaign, a public/private partnership that has led to 89% of the global population having access to iodized salt, protecting the brains of hundreds of millions of children.

Even today, over 120 countries have made iodized salt mandatory to combat iodine deficiency. However, simply increasing your salt intake is not a sustainable solution to this problem – a high-sodium diet carries many other health problems. The Folkehelseinstituttet recommends that the average daily salt intake be no more than 6g, and it’s estimated that many of us already eat around 10g daily. Luckily, we can find iodine and a natural, salty, umami flavor in seaweed and kelp!

Thyroid dysfunction

An overactive thyroid can lead to hyperthyroidism, whereas an underactive thyroid can lead to hypothyroidism. The American Thyroid Association, Inc. (ATA) estimates that up to 30% of the world’s population is at risk of hypothyroidism, mainly due to dietary factors. Check out our site for some of the symptoms of these conditions.

Can you have too much iodine?

Hyperthyroidism is most commonly caused by Grave's disease, an autoimmune condition where the body mistakes the thyroid gland for a foreign body and attacks it. Around 1 in 20 cases of hyperthyroidism are caused by thyroid nodules – benign lumps that grow on the thyroid and increase its capacity for hormone production beyond what the body needs.

Taking iodine supplements can trigger hyperthyroidism. This is sometimes referred to as the Jod-Basedow phenomenon. However, this usually only happens if you already have thyroid nodules, which account for a minority of hyperthyroidism cases. Most of the time, your body can deal with an excess of iodine like it deals with an excess of any other unwanted nutrient – it simply gets rid of it.

For adults, the recommended daily intake of iodine is 0.15 milligrams (0.25 milligrams for pregnant and breastfeeding women). This guideline varies slightly from country to country, so always check your country’s medical advice, or consult a doctor if you’re unsure.

Seaweed and iodine

Seaweed has been used to treat thyroid-related health problems for nearly 5,000 years. In 2,838 BCE, Emperor Shen Nung – regarded as the father of Chinese medicine and the inventor of acupuncture – wrote prescriptions for?seaweed?to treat goiter. Around a thousand years later, in 1600 BCE, its use was noted again in China, where burnt sea sponges and?seaweed?were used to treat the disease. In 1811, French chemist Bernard Courtis noticed that seaweed being burnt to get potassium nitrate gave off a purple smoke. He identified that active element as iodine by oxidizing the burnt seaweed with sulphuric acid. These were the beginnings of the public health successes we’ve seen with iodine today.

However, The American Thyroid Association, Inc. (ATA) has estimated that around 30% of the world’s population is at risk of iodine deficiency and that 5% of Europe’s population has either undiagnosed or diagnosed hypothyroidism. Adding just a pinch of seaweed or seaweed salt to your meal each day is a really great way to maintain a healthy thyroid, and keep your body in balance.

Explore how much of?our products?you’d need to consume to get your recommended daily allowance of iodine here.