I’m sharing another featured ingredient with you today on Hypothyroid Chef. Furikake is a traditional Japanese condiment and rice topping made from seaweed, sesame seeds, salt and sugar. There are dozens of variations on furikake, which refers to a sprinkly topping for rice, but here in the U.S. when someone says furikake (pron. Foo-dee-kah-ke), this basic sesame-seaweed shake is usually what they’re talking about.

Seaweed is one of the best natural food sources of iodine, which the thyroid depends on to function properly. It’s important to note, however, that iodine consumption paired with a selenium deficiency is bad news for the thyroid. You can read more about it here. Nori, or the dried sheets of seaweed your California roll is wrapped in, happens to be one of the main ingredients in furikake.

Furikake is so easy to make at home, and typically doesn’t require a specialty store scavenger hunt for the basic ingredients. This D.I.Y. Recipe for Vegetarian Furikake from The Kitchn takes a simple, vegan-friendly approach. But since I’m a chef and I like to get CraZy with flavor, I’ve included my own recipe (below) with the added oomph of bonito flakes. These thinly shaved bits of dried tuna give this furikake all the umami-power of bacon, in fish form. I was able to find the ingredients I needed at my local grocery store, but they have a pretty solid “Asian” section.

I could eat furikake by the spoonful, but I especially like it on a Japanese-style breakfast bowl. In the one pictured here, I used some leftover short-grain brown rice, an over-easy egg, peas, chives, and a drizzle of hot pepper sesame oil and tamari. A few slices of avocado would be nice, a slash or two of sriracha, maybe slivers of smoked salmon, or a handful of wilted chard. Whatever floats your boat. It’s always nice to have another warm and satisfying, gluten-free breakfast idea.

Another way you can easily add Furikake to your diet is to buy it, pre-made.  Sprinkle it on popcorn, eggs, rice, or fish. If purchasing furikake, be sure to check the ingredient list carefully, as some brands contain MSG or other chemical ingredients. This post originally recommended Nori Komi brand, which used to have a fairly clean ingredient list, but now contains a number of preservatives and chemicals, and bears the California Prop 65 warning label for cancer and lead. Sigh…

Food Sources of Iodine

I’ve been focused on natural sources of iodine lately, like fresh cranberries, seafood, yogurt, cheese, whole potatoes, eggs, milk, and of course, seaweed. You may already know that iodine is crucial to thyroid function, but did you know it wants just the right amount? Both too much or too little iodine can lead to goiter, hypothyroidism, or hyperthyroidism.

There is some disagreement in the American medical community as to whether our problem is too much or too little iodine, but it has been estimated that as many as 1 in 7 women suffer from iodine deficiency in the U.S. On the flip side, up to 90% of us with hypothyroidism in fact have Hashimoto’s or autoimmune thryoiditis, which may benefit from reducing iodine consumption. We must choose carefully, and with the help of our health care providers, whether focusing on iodine rich foods is beneficial to our thyroid health. One thing is true in all cases: Consuming iodine with a selenium deficiency is bad news for the thyroid. Read this article for a more thorough explanation on why iodine is controversial to thyroid health.

The recommended daily allowance for iodine in an adult is 150 mcg. That figure goes up to 220 – 250 mcg for pregnant women, and 290 for lactating women. 

It’s difficult to know how much iodine you’re consuming because the amount of iodine in foods varies widely depending on things like environmental factors and farming practices. The reason dairy, for example, contains iodine is due in large part to iodine supplements in animal feed, so values are always approximate. That said, here are some estimated values of iodine in food:

• 99 mcg in 3 ounces baked cod
• 75 mcg in 1 cup plain, low fat yogurt
• 71 mcg in 1/4 teaspoon iodized salt
• 30 mcg in 1/2 cup chocolate ice cream
• 24 mcg in 1 large egg
• 12 mcg in 1 ounce cheddar cheese
• 7 mcg in 1 cup apple juice
• 3 mcg in 1/2 cup frozen, boiled green peas

Source: National Institute of Health. Iodine. Office of Dietary Supplements. Fact Sheet for Health Professionals.

Iodine in Seaweed

Kombu: One food that registers off the charts for iodine content is kombu seaweed, otherwise known as kelp. It’s sometimes used as an ingredient in Japanese soup stock, which makes sense because boiling eliminates the extremely high concentration of iodine in this food, estimated at 2,660 mcg per gram (yikes!).

Wakame is another seaweed product, often re-hydrated and used in seaweed salads.  In an article entitled, “How Can I Safely Consume Seaweed?”  Wakame is noted as having a more moderate but still rather high amount of iodine, estimated at approximately 790 mcg per 100 grams (about a 3 1/2 ounce serving).

Nori: These papery sheets of dried seaweed used for sushi rolls, are listed as being relatively safe to consume at 12 mcg of iodine per gram. My digital kitchen scale measures a sheet of nori at about 2 grams, so iodine content would be in the neighborhood of 24 mcg per sheet.

There’s a fascinating tidbit in the article link above, about the Japanese diet which is relatively high in thyroid-stimulating iodine, but also in goitrogenic (or thyroid-inhibiting) ingredients like soy, bok choy, and broccoli. Coincidence? I doubt it.

Anywho, one opinion I come across regularly is that taking supplemental iodine is risky business. As a rule, I do not recommend supplements or making major dietary changes here on Hypothyroid Chef, because first of all, I’m a chef, not a doctor or dietitian. Secondly, I have seen far too many stories about the harm caused by un-prescribed or inappropriately prescribed supplements. If you wish to take supplements of any kind and are hypothyroid, please, seek out proper medical evaluation and advice first.

Hope this hypothyroid-loving seaweed shake finds a permanent place in your pantry. Enjoy!

Wishing you the best of health,

 

 

 

The Breakdown

• Iodine is a crucial element to the production of thyroid hormone, and since our bodies do not make it naturally, we depend on dietary sources.
• Dried seaweed is one of the best natural food sources of iodine. Nori, or the dried sheets of seaweed used in furikake, provides approximately 24 mcg of iodine per sheet. It is considered a low-calorie, high-fiber, cheap superfood with a 6-month shelf life.
• A tablespoon of sesame seeds provides 4% DV of Selenium, which aids in both the production and regulation of thyroid hormone. It also protects the thyroid from damage that can be caused from too much iodine.
• A tablespoon of sesame seeds provides 8% RDI for Tyrosine, which the thyroid gland combines with iodine to make thyroid hormone.