Thyroid Health and Selenium

BY Andrea Nakayama TIMEMarch 11, 2014 PRINT

There are so many factors that affect thyroid health. And when I talk about thyroid health, I’m talking to you.

Thyroid health isn’t something that just matters to those of us who have thyroid issues. We all have a thyroid—as long as, for some reason, it has not been removed. And we all want it to function properly. Believe me, we do.

Just like you don’t think about the big toe on your left foot and how you need it to walk until you stub it, or consider your molars and how they help you grind and chew your food until you have a tooth infection, the thyroid is one of those things we tend to ignore until it let’s us know quite clearly—with a number of signs and symptoms—that we can’t.

Why should you care about the health of your thyroid?

thyroid gland
The thyroid is gland is the primary control center for your metabolism. (Eraxion/

Let’s look at the main functions of your thyroid and the hormones it produces:

• Your thyroid is the primary control center for your metabolism.
• Your thyroid impacts growth rate if you’re young.
• Your thyroid helps you to breakdown and utilize the carbohydrates and fats you eat.
• Your thyroid aids in the conversion of beta-carotene from your plant foods into the fat-soluble vitamin A—necessary for proper immune, inflammatory, genetic, and reproductive health.
• Your thyroid affects your cholesterol levels, your blood pressure, your appetite, your mental sharpness, your libido, and so much more.

You want that baby working for you!

And it’s not a flick of a switch that takes the thyroid from functional to nonfunctional.

Stress, toxins, autoimmune conditions, infections, certain medication, fluoride, and deficiency in specific nutrients can all inhibit the necessary production of thyroid hormones. (Oh my.) The dysfunction will creep up on you like the first day of school after summer break.

There is one key nutrient consideration for thyroid health. It’s the controversial mineral—iodine.

For many, the squabble about this mineral is mitigated by the presence, or lack thereof, of another key nutrient for thyroid hormone production.

This second key nutrient is selenium.

Selenium is an antioxidant, a critical constituent in the production of thyroid hormones, and plays a vital role in the conversion of the primary thyroid hormone (T4) to the more bioactive thyroid hormone (T3). Selenium also counteracts the oxidative stress and inflammation that can come from an excess of iodine, and its byproducts, surrounding the thyroid tissue.

Whether thyroid issues are your concern, or iodine is in the picture for you or not, selenium should be.

When I co-taught an ‘Eat to Beat Cancer’ class years ago, foods high in selenium were at the top of the list. Selenium has several important functions in the body beyond the thyroid, and in today’s stressful climate, many of us are deficient in this important nutrient.

Selenium prevents against oxidative stress—which has been identified as a contributing factor in heart disease, rheumatoid arthritis, and cancer, among other things.

And speaking of top of the list, Brazil nuts are at the tip-top of the list of selenium-rich foods.

For years now I’ve recommend that people add Brazil nuts to their diet.

Perhaps two or three to start the day, or the same quantity carried in their purse or pocket for a midday snack. You may be thinking of the old, dry rancid Brazil nuts that you snacked around from the nut mix at your grandma’s house. But I’m talking about fresh succulent Brazil nuts, crispy, and buttery.

When armed with the best Brazil nuts, the recipient of my advice will inevitably come back to tell me that they love the Brazil nuts so much that they can’t stop eating them.

My response: take two!

If selenium is so great, why not eat a whole bag of Brazil nuts?

While there are many lifestyle and environmental factors that lead to unwanted selenium deficiency, selenium toxicity is not desirable either. It’s not a danger that many of us need to worry about, but regular consumption of mass quantities of Brazil nuts could, overtime, lead to adverse symptoms due to their high mineral stores. Not to mention that a large quantity may deliver more calories than most of us want or need.

Enjoy a recipe such as the tapenade below that incorporates the flavor and texture of these unique nuts. Otherwise, take two! (Two Brazil nuts a day that is.) And there’s no need to call me in the morning—unless it’s Saturday morning and you’re calling for the free workshop.

Note: Brazil nuts should be eaten raw, sprouted (soaked in water for an hour or two), or dry-roasted without salt.


Brazil Nut Tapenade

This is a very rich tapenade that can be served atop crostini, mixed with pasta like a pesto, or massaged into hearty greens. The richness depends on the intensity of the olives—use a milder olive for a mellower taste.

Ingredients (all organic):

1 cup sun-dried tomatoes, soaked about 2 hours in advance of preparation (or use oil-packed and drain)
3/4 cup pitted black olives
2 cloves garlic
1 cup packed flat-leaf parsley
1/2 cup raw Brazil nuts
1/2 cup cold-pressed olive oil
1/2 lemon, squeezed
sea salt to taste


Place all ingredients in a food processor and pulse until the tapenade is chunky.
Yields approximately 1 1/2 cups


Buying Brazil Nuts

  • Note: If your Brazil nuts taste rancid, they probably are. Most people have never experienced these nuts before they go bad. What a shame! A Brazil nut should taste creamy, sweet, and sometimes even a little smoky.
  • Talk to the buyer at your local health food store or co-op and find out how their Brazil nuts are being sourced, stored, and how long they sit on the shelf.
  • I like to buy mine from a trusted source and keep them in the freezer. Popping two or three Brazil nuts from the freezer is a great treat!


With a career born of a personal family health crisis and the loss of her young husband, functional nutritionist Andrea Nakayama has taken the idea of food as personalized medicine from a clinical practice to guiding thousands of international clients on the journey of taking ownership over their own health through her online programs at and Contact her at:

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