By Dr. Linda J. Dobberstein, DC, Board Certified in Clinical Nutrition
The human body is an amazing, elaborate creation with stunning complexity and beauty inside and out. Each and every day of breath and function, your body requires healthy nourishment. Water, protein, fats, carbohydrates, minerals, vitamins, enzymes, fiber, probiotics, and other nutrients are essential to the function and wellbeing of everything inside of you.
Your thyroid has many specific nutrient needs. A lack of any of these necessary nutrients makes it harder to maintain normal thyroid and metabolic function. Tissues become stressed and lose ideal function. It is critical to get proper nutrients from your diet, or if lacking, from supplementation. This keeps your thyroid system nourished and provides the best chance for optimal function.
The main hormones produced by the thyroid gland are thyroxine (T4) and triiodothyronine (T3). About 80 percent of the hormone is T4, with the remainder as T3. T4, which is primarily inactive, is converted into active T3 mostly in the liver, muscles, and gut. Stress, nutrient insufficiencies, and other factors may impair the conversion-activation process.
Thyroid hormone governs growth and development in prenatal and infant development and regulates proteins, fats, and carbohydrate metabolism in all ages. Thyroid hormone activity directly impacts mitochondria function, which drives burning of calories to generate energy and body heat.
The basic formation of thyroid hormones requires the amino acid tyrosine and the mineral iodine. Tyrosine is found in high protein foods such as dairy, cheese, meat, poultry, fish, eggs, nuts and beans. Your body may also convert it from another amino acid called phenylalanine.
Iodine is a mineral that must be obtained in the diet. Your body can’t produce it from other nutrients. Foods that naturally contain iodine include fish, seaweed, kelp, dulce, shrimp, dairy, and eggs. Iodized salt at ¼ teaspoon provides 71 micrograms (mcg) of iodine. The adult RDA for iodine is 153 mcg. Pregnant or nursing women require higher amounts 220-290 mcg of iodine for pre- and postnatal growth and development in the infant. Higher doses of 1000 mcg or more of iodine are used when tissue levels are depleted. An estimated 2 billion people have insufficient iodine intake across the world. Nearly one-third of school age children do not get enough iodine in their diet.
Vitamin A, Iron, Selenium, and Zinc
Several nutrients play vital roles in thyroid hormone activity. A lack of one or more of these nutrients may substantially impair thyroid metabolism and physiology. Vitamin A, iron, selenium and zinc, in particular, impact iodine function. These nutrients are required for iodine to do its job with thyroid metabolism. If inadequate levels are present with one or more of these nutrients, thyroid hormone production, function, and immune balance becomes like a broken factory assembly line that affects production of the final product.
Vitamin A
Vitamin A and iodine work together for thyroid hormone metabolism. For instance, it has been found that insufficient vitamin A intake “aggravates thyroid dysfunction caused by iodine-deficient diets”. In addition, Vitamin A regulates thyroid hormone metabolism and genes that signal thyroid stimulating hormone (TSH).
Iron
Normal thyroid hormone metabolism requires adequate iron. The enzyme (TPO) responsible for the production of thyroid hormone contains iron in its structure. If there is a lack of iron, your body will have difficulty making thyroid hormone.
Lack of adequate iron intake, leading to depleted iron stores in the body, is a very common concern across the globe. Inadequate intake of iron is commonly found in pregnant women, infants and young children, athletes, vegetarians, growing teenagers, women with heavy menstrual cycles, individuals who give blood, have cancer, gastrointestinal problems or heart failure.
Serum ferritin levels reflect iron stores within your body. Lab levels should be at least above 30 ng/mL. Optimal serum ferritin levels are at least between 50-100 ng/mL. Low iron stores also affect your muscles, sleep, mitochondria, and energy production.
Selenium
Selenium contributes in several ways to thyroid function. This trace mineral provides antioxidant support by quenching damaging free radicals (ROS). Selenium aids in the production and recycling of the master antioxidant enzyme system with glutathione that provides critical protection to the thyroid gland and immune system balance. Selenium plays several critical roles in converting non-active T4 thyroid hormone into active T3.
Your thyroid gland contains the highest concentration of selenium anywhere in the body. That’s how critical it is for normal thyroid function. Selenium is used to quench free radical stress in the thyroid gland. Your body requires adequate selenium in the thyroid in order to make new mitochondria. If there isn’t enough selenium to go around, then more free radicals are produced and your energy producing factories (mitochondria) within your thyroid are compromised.
Zinc
Zinc is a trace mineral needed for several actions pertaining to thyroid function. It has complex interactions with the production and activation of thyroid hormone. It affects enzyme systems regulating thyroid hormone and impacts thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH). Zinc also affects transportation of thyroid hormone and the receptor sites that receive it.
Other Essential Nutrients: Gut Flora, Magnesium, Vitamin D and B Vitamins
Current research shows that your gut flora markedly influences iodine uptake, breakdown, and metabolism of it in the liver. Your gut microbiome also interacts with iron, selenium, and zinc. Healthy gut flora helps support thyroid health.
Magnesium is often thought of for heart health, blood pressure, stress and relaxation, but this mineral helps thyroid health too. When your body stores run low with magnesium, it can cause significant distress to the thyroid-immune system balance. Magnesium helps calm irritation and stress signals while supporting the thyroid-mitochondria link.
Vitamin D is also critical for the thyroid system. It aids in the protection of the thyroid gland. Vitamin D regulates multiple signaling and metabolic pathways that work together with thyroid hormone. It helps balance immune signals which are important to protect the thyroid gland from immune stress. Every cell that uses thyroid hormone also uses vitamin D. If vitamin D is low, it will affect cellular function.
B vitamins are needed too for the interrelationship with thyroid and mitochondrial function as well as methylation. You can read about this in the recent article Thyroid Health Depends on Balanced Methylation.
Manganese is a trace mineral that complements selenium’s antioxidant activity which aids in protecting the thyroid against free radical stress. It also helps cells make heat and energy. Imbalanced intake of manganese may affect adversely impact thyroid function.
Stressors That Deplete
Individuals who have adopted low carbohydrate diets may unknowingly cause insufficient consumption of nutrients needed for thyroid and metabolism. A recent systematic review study identified decreased intake of thiamin (vitamin B1), folate, magnesium, calcium, iron, and iodine with any type of carbohydrate restricted diets. Individuals often use these diets to induce weight loss, but the payoff is that these diets increase nutrient deficits necessary for your thyroid and metabolism. Other restricted diets, gastric bypass/weight loss surgery, or even eating the Standard American Diet results in insufficient nutrient intake and depletion of nutrients.
Remember too that medications interfere with thyroid function. Many drugs also deplete nutrients. Medications that affect adversely affect thyroid function include estrogen therapy, birth control pills, steroids, anti-seizure medications (phenytoin) and even aspirin containing products. Check with your pharmacist as this list is not all inclusive.
Despite the abundance of foods and easy access, nutritional needs are often not met in today’s society. Instead, calorie-rich, nutrient-poor or imbalanced choices are consumed. Iodine, iron, zinc, selenium, magnesium, vitamins A, B, and D are critical for thyroid function throughout your entire body, yet so many individuals fail to consume necessary daily needs. Tissues stores become depleted. Think about these consequences that occur day after day, year after year. At some point, the unquenched free radicals and the stressed physiology will catch up to you. You may call it the effects of stress and aging, but thyroid metabolism and your whole being requires adequate nutrient reserves. Is your body going to be like a broken down, rusted out, smoke-spewing, engine-sputtering car or do you take care of it to run smoothly and keep in excellent, working condition?
