This guest post is from my newest Functional Nutritionist to join the team — Erica Favela! Erica is sharing the top ‘thyroid foods,' the foods she recommends for people in need of a little thyroid love and answering the question, “What foods are good for my thyroid?”
You may not know this, but us ladies have a higher risk of developing a thyroid condition — like 5 to 8 times more likely to have thyroid disease. Knowing how to nourish your thyroid is one of the foundational steps in keeping your thyroid (and really, all your hormones) healthy and preventing a thyroid disorder.
Remember, if you suspect you have a thyroid disease then it is important that you meet with a qualified professional to get the labs testing you need and unearth your root cause.
Here's to awesome thyroid health!
Dr. Jolene Brighten
What Foods are Good for My Thyroid?
I’ll never forget the day I found out that eating a kale salad everyday for lunch wasn’t great for my thyroid health.
What?! How could kale not be good for me?!
The problem wasn’t necessarily with kale itself (it’s still one of my favorite veggies), the problem was that I was eating raw kale every. single. day. And juicing it for breakfast too. I was eating about 4 cups of raw kale a day!
At that time, I had a very narrow idea of what “healthy” meant. Little did I know that the foods we eat can affect our hormones and endocrine system. As I began studying nutrition, I learned that foods have naturally occurring compounds called goitrogens. Consumed in excess, these can have a negative impact on the thyroid gland.
The thyroid is responsible for some major functions in our body. Things like controlling our metabolism, regulating body weight and body temperature, and determining our energy levels. It even impacts fertility. Personally, I want to have steady energy all day long and a metabolism that’s on my side, and if you do too, then it’s important to take care of your thyroid.
The signs and symptoms for an unhealthy thyroid range widely, but some of the common complaints include fatigue, unexplained weight gain or weight loss, depression, constipation, sleep disturbances, and more. These symptoms can have a serious impact on our everyday experience of life, and whether you know you have a thyroid condition or not, eating in a way that supports the thyroid can support your overall well-being.
Thyroid Foods and Nutrients
There are several different types of thyroid conditions, and the most common is hypothyroidism, or having an underactive thyroid. In most cases, the root cause of hypothyroidism is an autoimmune disease called Hashimoto’s Thyroiditis. While dietary guidelines for treating hypothyroidism versus an autoimmune disease vary slightly, the foundational nutrients your thyroid needs to function at its best remains the same.
8 Nutrients for Thyroid Health
The thyroid is sensitive to selenium deficiency. Selenium is a crucial component of the enzyme that converts T4 (inactive hormone) to T3 (active hormone) in the body.
A deficiency in selenium can result in less active thyroid hormone available which will result in symptoms of hypothyroidism.
Some studies have shown that a selenium deficiency can have a negative impact on thyroid health. The richest food sources of selenium include organ meats and seafood, followed by muscle meats.
The selenium content of plants and grains will vary as it depends on the selenium content of the soil in which it was grown. For instance, one ounce of Brazil nuts grown in selenium-rich soil contains around 554 micrograms of selenium. Brazil nuts grown in selenium depleted soil can have about ten times less.
See below for an easy, non-dairy Brazil Nut Parmesan.
The thyroid gland synthesizes iodine and the amino acid tyrosine to create thyroid hormone, so it is essential for thyroid health. The recommended daily allowance is quite low at 150 micrograms and it’s easy to get this mineral naturally by eating seafood and seaweeds. A three-ounce serving of cod offers 99 mcg of iodine, and three ounces of shrimp contains around 35 mcg.
Too much iodine, however, can inhibit thyroid synthesis. Since table salt and other foods are fortified with iodine, many people in industrialized nations are not iodine deficient. Since the primary function of iodine in the body is for thyroid synthesis, supplementation of this mineral is usually unnecessary if your diet includes ample sources of iodine.
Furthermore, high levels of iodine are used for thyroid suppression therapy, therefore high dose iodine supplementation would never be recommended for hypothyroidism or Hashimoto’s. In addition, iodine supplementation in the presence of a selenium deficiency can make autoimmune thyroid disease worse.
If you're thinking about starting iodine supplementation, please meet with a doctor first to determine if this is the best treatment for your specific needs.
A deficiency in vitamin D is associated with several autoimmune diseases and specifically with thyroid disease. Sufficient amounts of vitamin D support immune cells in making sure they are attacking outside invaders and not ourselves. In the case of autoimmunity, the receptor sites for vitamin D are diminished due to polymorphisms, and thus its biological effects on immunity are reduced.
The skin is able to synthesize vitamin D so one of the easiest ways to get this vitamin is through exposure to natural sunlight.
Vitamins D is found in few foods, including mackerel, salmon, and sardines, or fish liver oils. For this reason, many foods are fortified with vitamin D. However, I always encourage getting nutrients in naturally occurring, whole food form to ensure quality and bioavailability.
A three-ounce serving of sardines offers 4.1 micrograms of vitamin D, and three ounces of canned salmon has 11.6 micrograms.
Having vitamin D testing is essential before beginning supplementation.
Essential Fatty Acids.
Essential fatty acids establish and maintain cell membrane integrity and fluidity in the thyroid gland. Additionally, inflammation can decrease thyroid receptor function and decrease conversion of T4 to T3. EFA’s play an important role in preventing and reducing inflammation.
Sufficient amounts of EFA’s promote proper hormonal balance, mental clarity, and steady energy levels throughout the day. Excellent food sources of EFA’s include cold-water fatty fish such as herring, salmon, sardines, and oysters.
Magnesium participates in at least three hundred enzymatic reactions in the body. In cases of severe thyroid hormone deficiency, blood pressure rises as a result of a loss of plasticity of blood vessels. It plays a role in regulating blood pressure by preventing excessive contraction of the vessels.
Magnesium is an important component of chlorophyll and is found in large amounts in green vegetables. A ½ cup serving of cooked spinach include 78 mg of magnesium. Other good sources include unrefined grains and nuts. One cup of brown rice has 86 mg, and an ounce of almonds has 77 mg of magnesium.
Zinc works together with vitamin A and E to manufacture thyroid hormone, and is also a necessary cofactor along with copper and selenium in converting T4 to T3. Further, zinc also assists in many other hormone activities, including growth hormones and insulin, and is critical for immune function.
The most bioavailable forms of zinc can be found in shellfish, beef, and other red meat. Oysters are one of the most well-known sources of zinc; six medium-sized cooked oysters offer 27-50 mg of zinc. Zinc present in other foods like whole grains, legumes, and nuts is mostly unavailable to the body for absorption, due to its binding with phytic acid.
Iron contributes to the proper production of thyroid hormones, and studies have shown that a deficiency in iron can have a negative impact on thyroid function. Without iron, individuals especially with underactive thyroid can struggle with the ability to heal the thyroid and raise T3 without having hyperthyroid-like symptoms.
Iron also aids in maintaining proper immune function, which is important in the case of underlying autoimmunity.
Iron deficiency is common in those with hypothyroid. Too little thyroid hormone makes it near impossible to liberate and absorb your nutrients. Read more about gut & thyroid health here.
The most absorbable form of iron is found in animal sources and is called heme iron. One ounce of chicken liver delivers 3.6 mg, and three ounces of beef has 1.3 mg of iron. Non-heme iron is found in plants, and its absorption is influenced by other dietary factors. Vitamin C, for instance, can enhance the absorption of nonheme iron, while phytic acid can inhibit it.
This vitamin is often deficient in people with any type of autoimmune disease, with Hashimoto’s being no exception. Vitamin A is an antioxidant and important for immune function.
Dendritic cells that communicate to the immune system need vitamin A to prevent excessive immune reactions. For the thyroid, vitamin A works together with zinc and vitamin E to convert T4 to T3 in appropriate amounts.
Vitamin A that is preformed and ready to use by the body is called retinol and can be found animal products such as liver, egg yolks, and grass-fed butter. One teaspoon of cod liver oil has 1,350 micrograms of retinol. One egg contains 80 micrograms of retinol.
Other forms of vitamin A are carotenoids, and these are precursors to vitamin A. Carotenoids can be found in yellow and orange colored vegetables such as sweet potatoes and carrots, as well as other green vegetables. The conversion rate from carotenoids to retinol varies.
Are Goitrogens Bad for Your Thyroid?
Fortunately, the short answer is no! The most common types of goitrogenic foods are cruciferous vegetables, such as cabbage, kale, broccoli, and Brussels sprouts.
These foods are nutrient powerhouses serving as excellent sources of vitamin C, potassium, folic acid, vitamin B6, calcium, and magnesium.
Several studies have been conducted on cruciferous vegetables and their anti-cancer compounds. Due to their high nutrient density, completely eliminating foods in this family would not be a good idea.
The safe amount of goitrogenic foods in your diet will depend on your unique nutritional status, especially your amount of iodine. Low levels of iodine have been associated with increased sensitivity to goitrogens.
Goitrogenic foods are something to be aware of, but definitely not something to fret about!
In the case that you have a hypothyroid condition, it’d be best not to have goitrogen containing foods raw, and in large quantities. For instance, do not eat a raw kale salad every single day for lunch (like I did). Also, most forms of cooking reduces goitrogens.
If you’re eating a varied, balanced diet, chances are you are not over-eating goitrogenic foods to the amount that they are having a negative impact on your thyroid.
Consuming sauerkraut as a condiment, or having one to three serving of cruciferous vegetables per day, is unlikely to have a significant negative impact on your thyroid health, unless you are iodine deficient. In fact, these foods might be just what you need to feel better!
A Day of Good Thyroid Foods
It’s great to know all the above nutrients and their role in the body, but what does this mean for what we actually eat? Fortunately, you don’t have to calculate the nutrients of all your meals. Stick with a whole food diet that includes balanced meals of protein and fat, along with plenty of nutrient-dense vegetables and a few booster foods.
Here's a taste (pun intended) of what I offer my clients:
2-3 egg omelette with spinach, mushrooms, and green onions. Serve with tomato and avocado and a hot mug of green tea or bone broth.
Grilled chicken and a large baby green mixed salad with shredded carrots, sliced red bell pepper, and brazil nut parmesan with dressing of lemon juice, garlic, and extra-virgin olive oil
Baked salmon and asparagus alongside red leaf lettuce salad with toasted almond slivers and dulse seaweed.
Celery sticks with almond butter, sliced cucumbers and black olives, or 2-3 slices of deli meat and 1-2 brazil nuts.
Need More Support? We’re here to help!
If you’re wondering about the status of your own thyroid, it’s important to get tested. And, if you already know you are dealing with hypothyroidism, don’t forget to download your very own thyroid handbook.
There is so much diet dogma out there that can make us feel crazy. But helping people develop the best individualized diet for them just happens to be my specialty! For more support and guidance on your healing journey, you can schedule a time to chat with me here. I'd love to help you feel your best!
Recipe: Brazil Nut “Parmesan”
1 cup brazil nuts
1-2 garlic cloves, microplaned or minced
1/2 teaspoon sea salt
Mince the garlic, or grate using a microplane. I personally like the microplane, as it really brings out the taste and allows the garlic to spread easily throughout.
Place all ingredients in a food processor and pulse until the nuts are crumbled. Taste and adjust with more salt or garlic.