At the Dietitian

How to Safeguard Your Thyroid Gland in a Toxic World

By Tamar Feldman, RDN, CDE

Thyroid diseases are more common than you may believe and affect millions of people worldwide. The thyroid gland plays a pivotal role in health as the active form of thyroid hormone, T3, assists in regulating cardiovascular and neurological function, supporting immunity, metabolism, and energy levels. Recently, thyroid diseases have been increasing, and this has motivated researchers to investigate the cause. They found that several environmental toxins are at least contributing to thyroid diseases and should be avoided to protect thyroid health.

When the body attacks the thyroid gland, as is the case most of the time with thyroid disorders, it is usually because the iodine and thyroid hormones stored in the gland become oxidized or in some cases even bound with similarly structured dietary and environmental toxins. The body then seeks to repair this damaged thyroid hormone by producing auto-antibodies against it.

If you are concerned about preventing thyroid damage, or you already have some degree of thyroid imbalance and would like to halt the auto-immune process, you would be wise to consider minimizing your exposure to these environmental toxins.

Environmental toxins that mirror thyroid hormone structure and invade the thyroid gland can be categorized as:

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Heavy Metals Agricultural Agents

Heavy metals such as mercury, aluminum, and lead are very damaging to the thyroid gland. Aluminum is commonly found in toiletries like deodorant, over-the-counter medications like antacids, food additives, and cookware, while mercury is found in dental fillings and seafood. These heavy metals oxidize the thyroid, inhibit iodide uptake, limit thyroid hormone production, and can mislead the immune system into attacking the thyroid, as seen in autoimmune disease. On a practical note, I advise individuals to line aluminum pans with parchment paper, to use natural deodorant, and to use low mercury tuna brands such as safe-catch.

Household Toxins

Flame retardants, present in modern-day furniture, carpet, and clothing made of synthetic materials can play a role in blocking T4 from being transported in the blood. Bisphenol A (BPA) and phthalates, ingredients used to make plastic for water bottles, children’s toys, and food storage containers, imitate the structures of other hormones found naturally in the body and disrupt the entire endocrine system along with the thyroid. BPA also prevents T3 from binding to cell receptors. Thyroid function is also diminished by triclosan, an antibacterial agent found in some liquid hand soaps, and PFOA, an agent used in stain-resistant fabrics, food wrappers, and nonstick cookware. It is advisable to avoid antibacterial soaps, to store and heat food only in glass or china rather than plastics, and to cook in stainless steel pots rather than nonstick pans.

Perhaps the main culprits that come to mind in discussions of environmental toxins are pesticides, herbicides, and fungicides. This class of chemicals can weaken thyroid function to the point of causing hypothyroidism. Agricultural agents wreck thyroid function by preventing the uptake of iodine into the thyroid, blocking thyroid hormone from binding to its transport proteins, lowering the absorption of thyroid hormone into thyroid cells, and promoting thyroid hormone removal from the body. It is advisable to choose organic foods as often as possible, particularly for the “dirty dozen: (see sidebar) heavily sprayed foods list, as well as heavily sprayed grains and legumes, including wheat and oats.

• Strawberries • Spinach • Kale, collard, and mustard greens • Nectarines

• Apples

• Grapes • Cherries

• Peaches

• Pears • Bell and hot peppers

• Celery

• Tomatoes

The Dirty Dozen

Tamar Feldman, RDN, CDE is registered dietitian/nutritionist and certified diabetes educator who has advanced training in functional medicine. She maintains a busy nutrition practice in Lakewood, Edison, and via phone/Skype to numerous international clients. She specializes in sustainable weight loss and nutrition therapy for autoimmune disease, gastrointestinal disorders, and female hormone imbalances. She can be reached at 732364-0064 or through her website, www.thegutdietitian.com.