The role of diet, supplements, and exercise
Jenny Schmidt-White, ND
Sixty percent of people who have a thyroid condition go undiagnosed. Learn what symptoms to look for, and the role that natural thyroid support can play.
Thyroid dysfunction is common among women in North America. While medication may be indicated, natural thyroid support, in the form of nutrition and lifestyle factors, is crucial for maintaining a healthy thyroid state.
The thyroid is a small but mighty butterfly-shaped gland at the base of the neck, manufacturing hormones for metabolism and growth in the body. The thyroid produces two main hormones, T4 and T3, which are made of iodine and the amino acid tyrosine.
The majority of thyroid hormone production is T4 (the number 4 represents the number of iodine molecules attached to tyrosine), which is considered inactive and does not affect metabolism directly. T3, the active thyroid hormone, is formed within the cells of the body with the help of selenium.
Thyroid conditions are common in North America. Hypothyroidism, a slow or underfunctioning thyroid gland, increases in likelihood with age, affecting women four to seven times more than men.
Hypothyroidism is most commonly due to Hashimoto’s thyroiditis (an autoimmune condition), followed by thyroid radiation (a treatment for some hyperthyroid conditions), and thyroid surgery. Other causes include congenital hypothyroidism, medication side effects, pregnancy, iodine deficiency, and pituitary disorders.
It is estimated that 60 percent of people with a thyroid condition are undiagnosed. Diagnosis of a hypothyroid condition is via blood testing, signs that your doctor may notice, and reported symptoms.
The traditional blood test used to diagnose hypothyroidism is TSH (thyroid stimulating hormone), which will be elevated in a hypothyroid condition. Additional testing can include free T4, free T3, and thyroid antibodies to investigate an autoimmune cause.
Medical treatment for hypothyroidism most commonly involves prescribing a synthetic T4 hormone. Naturopathic doctors (in some provinces) may also prescribe dessicated thyroid hormone, which contains T4 and T3.
Botanicals, dietary changes, minerals, and lifestyle choices can all influence the overall health of the thyroid gland and support traditional thyroid treatment.
In addition to its antioxidant, anti-inflammatory, and stress adaptation actions, the botanical Withania somnifera (ashwaganda), shows improvement in hypothyroidism by increasing circulating T4.
Selenium is an essential mineral for thyroid hormone health. Once the T4 hormone gets into a cell, it is converted to T3 with the help of selenium. Adding selenium in the diet has demonstrated benefits in the adjunctive treatment of Hashimoto’s autoimmune thyroiditis. Selenium can be found in Brazil nuts, mushrooms (portobello, shiitake, crimini), salmon, tuna, halibut, chicken or turkey, eggs, pinto beans, and couscous as well as in supplement form.
Zinc is a useful mineral in many cellular processes. Zinc aids in immune function, hormone pathways, and sperm development, and is also helpful for thyroid hormone production. Supplementation with zinc may not be necessary if dietary sources are widely consumed. Food sources of zinc include pumpkin and sesame seeds, turkey and chicken, lentils, chickpeas, cashews, and quinoa.
Iodine is an essential part of manufacturing thyroid hormones. Iodine deficiency is not as common in North America since iodized salt was introduced, but if avoiding iodized salt, consider dietary sources of iodine. Iodine is most prevalent in sea vegetables such as kelp, wakame, dulse, and arame, and can also be found in scallops, egg yolk, cod, sardines, and yogurt.
Tyrosine, another building block of thyroid hormones, is readily obtained in the diet. Great sources of tyrosine include spinach, egg whites, fish, cheese, chicken, turkey, and soybeans.
Dietary changes can also improve thyroid treatment outcomes. Gluten intolerance has been associated with autoimmune thyroid disorders, suggesting that gluten elimination may benefit thyroid conditions like Hashimoto’s thyroiditis.
Isoflavones, compounds found in the brassica family, are known as goitrogens and can slow thyroid function. Cooking these vegetables, including cabbage, kale, and broccoli, before eating can decrease the goitrogenic effect.
Adequate caloric intake is recommended to avoid reducing T3, as caloric restriction has been shown to slow thyroid function. For an active lifestyle (2 1/2 hours a week of moderate to intense activity), Health Canada recommends daily caloric consumption of 2,900 Kcal for men and 2,250 Kcal for women.
Endurance exercise is more beneficial than high- intensity interval type training for thyroid support and maintenance of adequate circulating thyroid hormones, particularly T4. Walking, hiking, biking, and running are all great endurance activities.
Exercise includes yoga, and a regular yoga practice improves symptoms of hypothyroid, including improving immune function. The addition of pranayama, yogic breath work, supports healthy lung function in hypothyroid conditions.
Environmental toxins including mercury, lead, and pesticides impair thyroid function. The hypothyroid effect is more pronounced in women than in men, and in pregnant women with exposure to mercury.
Mercury is most commonly found in freshwater fish, dental amalgams, and fluorescent light bulbs, and is used in mining practices, coal combustion, and waste incineration. If there is concern or question over exposure, consulting a health care practitioner is recommended.
Perchlorates, nitrates, and fluoride can all disrupt the absorption of iodine into the thyroid, impairing thyroid hormone production. Supportive thyroid measures may include minimizing cured meats (salami, bacon, hot dogs) and fluoride (fluoridated water, black tea, seafood) and consuming organic fruits and vegetables.
As with many imbalances, changing everyday habits provides lasting support for overall health. In conjunction with supervised thyroid treatments, thyroid health can be supported nutritionally and with lifestyle modifications.
Without sufficient thyroid hormone production, individuals may experience