An under-performing thyroid is an extremely common condition, especially for women around the time of the menopause. Although the functioning of the thyroid will be explained elsewhere, it is worth giving sea vegetables an article on their own, as they are an amazing and neglected nutritional resource.
One of the main nutrients used by the thyroid is Iodine. This is used to produce hormones that go on to regulate much of the body’s metabolism. In 2010, over 187 million people globally were diagnosed with hypothyroidism caused by iodine deficiency, and crucially, most of these deficiencies occur in areas further from the sea.
Iodine occurs in food as the salt iodide, and is found in fish, shell fish, yoghurt, milk, eggs and iodised salt. But the foods containing the greatest concentration of iodine are sea vegetables, or seaweeds. Sea vegetables are currently being researched for anti-cancer, anti-inflammatory, antibacterial and antiviral properties. The Japanese have been consuming sea vegetables for over 10,000 years, where they are used to treat gastrointestinal disorders, fatigue, hypothyroidism, skin inflammation and high cholesterol levels.
There are 3 main types of sea vegetables:
Brown algae: Kombu, kelp, wakame, arame, hijiki
Red algae: Agar agar, dulse
Green algae: Sea lettuce, chlorella
What makes sea vegetables so great?
They contain a huge array of vitamins, minerals and other nutrients. In particular, they contain the following:
Vitamins: Vitamin K, vitamin C, vitamin E, folic acid
Minerals: Iodine, iron, magnesium, calcium, copper, iron, manganese, molybdenum, phosphorus, potassium, selenium, vanadium, zinc
Other nutrients: Carotenoids, lignans, flavonoids, chlorophyll, tryptophan, Omega 3 and Omega 6 fatty acids, alginic acid and fucoidans.
The lignans are important for women going through the menopause as they act as phytoestrogens, replacing the body’s naturally falling oestrogen levels. In post menopausal women, studies in Japan have shown that sea vegetables can help modulate oestrogen metabolism.
The alginic acid helps remove toxins from the body, which is why the Japanese traditionally used sea vegetables as a blood cleanser. Chlorella has been shown to be able to help stimulate the immune system by increasing the number and activity of white blood cells. On top of that, the brown seaweeds contain a unique indigestible and insoluble fibre which acts as a prebiotic in the body; increasing the levels of beneficial probiotic bacteria in the small intestine.
How do I use them?
The different types of seaweed can be prepared and eaten in different ways.
Kombu is sold as a wide strip or sheet of dried sea kelp. A piece of kombu placed in a pan of boiling beans and pulses can help reduce the ‘gas’ factor. Kombu adds depth of flavour to slow-cooked dishes, and is used to prepare the Japanese soup stock, dashi.
Nori is usually sold in sheets to make sushi. It disintegrates on cooking and should be eaten raw.
Wakame is mild and slightly sweet and turns bright green on soaking. Soak for 15 minutes, drain, rinse and squeeze out the excess liquid. It makes a delicious addition to salads ( see recipes), but avoid cooking it as it can become slimy.
Dulse have red leaves or flakes with a mild, slightly salty and earthy taste. Again, just soak it for about 10 minutes, drain and rinse before eating.
Arame has wiry dark brown strands with a mild sweetness and a slightly chewy texture. Soak for 10 minutes, drain and rinse. It’s especially good mixed with root vegetables.
Hijiki is similar to arame, but with a stronger, slightly anise-like flavour. Soak for 20 minutes before draining and rinsing.
CAUTION! Make sure you buy your seaweeds from a reputable source, such as ClearSpring in the UK. Sea vegetables have a high potential for contamination with toxic minerals as they absorb so much from the water in which they grow.
CAUTION! Don’t go mad with sea vegetables if you are not used to eating them. A sudden high intake of iodine can precipitate an autoimmune attack on the thyroid, although this is more likely to affect those who already had an underlying thyroid problem. So introduce them slowly!