Supplements and foods that boost your thyroid — and what to avoid

Over the last two weeks, we’ve been focusing on your thyroid health. If you want to review those articles, just read Low thyroid function causes high health risks and What’s behind low thyroid function?.

Today I’ll share how supplementation improves symptoms and health in several ways. I’ll also discuss foods that affect thyroid hormone function.

Thyroid supplementation

If your blood tests, symptoms, and basal body temperature point to low thyroid function, then you will definitely benefit from taking thyroid hormone. Your doctor will readily prescribe synthetic levothyroxine (Synthroid®, Levoxyl®, Tyrosint®).

However, I find that most patients actually feel better and get their sluggish organs working better by using a natural thyroid hormone which contain actual thyroxine and triiodothyronine. Common names are Armour, Naturethroid, Westthroid, and compounded T4+T3. These come from pig’s thyroid glands. They contain natural enzymes to enhance conversion of T4 (thyroxine) to the more biologically active T3 (triiodothyronine) along with the hormones themselves.

That’s probably because newer research [1] in animals and humans shows that conversion of T4 to the more active T3 is variable, depending on your genes that control this. They found out that you can have impaired thyroid function on T4 supplementation and get symptom improvement by taking a combination of T4 and T3, without even seeing a change in serum thyroid hormone levels. [2]

Go online and you’ll find plenty of patient testimonials about how much better they feel after switching to a natural thyroid hormone prescription from the synthetic versions. Note that you may need to go to a compounding pharmacy to get the natural ones.

I believe it may be a challenge to find a physician who is willing to prescribe natural thyroid hormone. If so, here are some tips:

  • Go to a local compounding pharmacy and ask the pharmacist who prescribes natural thyroid hormones locally.
  • Ask your friends if they know of doctors (Medical Doctors or Naturopathic Doctors) who do saliva hormone testing (they will likely understand adrenal dysfunction).
  • Email the Broda Barnes foundation in search of a doctor near you who is trained or registered with their organization: info@BrodaBarnes.org.
  • Ask your doctor to check you for free T3, free T4, thyroid antibodies, and reverse T3 (rT3) levels. Explain that there is now science showing that measurable thyroid levels may not reflect exactly how thyroid hormone is functioning in the peripheral body tissues and cells depending on one’s genetic variation (some estimates from 12 to 36% of the population). Then ask your physician if he/she is willing to treat you with natural desiccated thyroid based on signs, symptoms, and body temperature primarily, not solely on TSH levels.
  • Ask if your doctor understands the role of cortisol and adrenal fatigue on body symptoms, as your proper dose of thyroid hormones will need to increase for many months until both cortisol and thyroid function are optimized so that your low thyroid symptoms disappear (without signs or symptoms of thyroid excess of course).

Blockers of thyroid hormone

Coffee consumption within 30 minutes of thyroid hormone supplementation blocks intestinal absorption of thyroid hormone. [3] Also, antacids, calcium and iron supplements taken within two hours of thyroid hormone can have a similar effect. [4]  There is a list of medications [5] known to lower thyroid function, none of which I hope you are taking. Mercury exposure has been correlated with lower thyroid hormone levels. [6] [7]

Stress is another way to suppress thyroid hormone. Stress triggers cortisol secretion from your adrenal gland. This is known to inhibit thyroid hormone production by lowering thyrotropin (thyroid stimulating hormone). [8]

Also be aware that gluten protein found in wheat, barley, rye, spelt, kamut, and triticale is not safe for people with celiac disease, and celiac disease is found to be 2 to 5 times more prevalent in persons with autoimmune thyroid disease. [9] The connect here is that gluten causes a “leaky gut” effect in which unwanted proteins and molecules to pass from the small intestine into the blood stream where they trigger auto-immune inflammation [10] [11] [12] of various types, including the auto-immune condition, Hashimoto’s thyroiditis. Thankfully, autoantibodies can disappear 6 months after going gluten-free. [13]

There are even healthy foods that contain substances known to interfere with thyroid function, called “goitrogens.” The science dates back to 1928 when cabbage consumption was linked to thyroid enlargement in laboratory animals. [14] The goitrogenic foods include cruciferous vegetables such as broccoli, cabbage, cauliflower, Brussels sprouts, turnip, Chinese cabbage, kale, spinach, rapeseed, common radish, horseradish, rutabaga, wasabi, capers, mustard oil, papaya, watercress, and other less-known plants. Later, various articles on dietary goitrogens in diverse animal species were reported, but only a relatively small number of foods had anti-thyroid activity in man. [15]

Foods that boost thyroid function

It is good to also know the dietary ways to improve thyroid function:

  • Animal protein from pastured beef, eggs from range chickens, mercury-free fish and shellfish, cheeses, eggs and dairy, as well as protein in fruits, vegetables, seeds and nuts help support healthy thyroid function.
  • Fresh organic produce from leafy greens, green beans, colorful vegetables, fruits, seeds, nuts and non-gluten grains such as brown rice, oats, buckwheat, quinoa, cornmeal, sorghum, and amaranth.
  • Healthy oils such as coconut oil, avocado, olive oil and others high in omega-3.

Nutrients to enhance thyroid function

Iodine: While it is true that lack of iodine can be one cause of hypothyroidism, this cause is not common in North America. Iodine is most plentiful in seaweed, seafood, dairy products, grain products, eggs, and less so in fruits and vegetables. [16]

To find out if you are getting iodine in a healthy range for you, have a healthcare provider to paint a small (half-dollar size) area on your inner forearm skin with 2% iodine tincture and if it disappears in less than 12 hours you’re considered iodine deficient; 12-24 hours means you’re mildly deficient. Alternatively, you could get a 24 hour urinary iodine level after a 50 mg iodide/iodine tablet oral load. If it is low, supplementation could be recommended at 150-200 mcg daily. [17]

Vitamin D-3:  In a 2011 issue of Thyroid, low levels of vitamin D were associated with worsened thyroid function in patients with Hashimoto’s thyroiditis. [18] Make sure you are getting enough vitamin D3 or 20 minutes of sunlight daily (enough sunlight for your skin to make adequate amounts).

Herbs that enhance thyroid function are:

  • Sea Kelp (Ascophyllum nodosum) provides a natural iodine source. Also, it protects thyroid cells from inflammation the interference with uptake of iodine that is caused by hydrogen peroxide during thyroid-hormone synthesis. [19] This effect is shown to decrease the risk of autoimmune thyroid disease. [20]
  • Bladderwrack (Fucus vesiculosus) also provides a natural iodine source. Also, it has anti-estrogen properties, thereby reducing the risk of thyroid gland inflammation by estrogen in both men and women. [21] [22]
  • Hops (Humulus lupulus) contains xanthohumol, which enhances iodine uptake into the thyroid gland. [23]
  • Coleus (Coleus forskohlii) has thyroid stimulating effects on iodide uptake, thyroglobulin, T4 & T3 production, and enhances T3 & T4 secretion. [24]
  • Ashwagandha (Withania somnifera) raises serum levels of thyroid hormones by acting directly on the thyroid gland [25] [26] and even raised thyroid hormone levels too high in a woman who took too high a dose of ashwagandha. [27]
  • Guggul (Commiphora mukul) directly stimulates triiodothyronine (T3) production via action on liver enzymes. [28]
  • Rosemary (Rosmarinus officinalis) and Sage (Salvia officinalis) both increase thyroid hormone-specific receptors on target tissue cells. [29] [30]

I hope by now you have a whole new perspective on how to correct low thyroid hormone function and can be empowered to do something about it.

To feeling good each day,

Michael Cutler, M.D.
Easy Health Options

[1] Werneck de Castro JP, Fonseca TL, Ueta CB, et al. Differences in hypothalamic type 2 deiodinase ubiquitination explain localized sensitivity to thyroxine. J Clin Invest. 2015 Feb;125(2):769-81.
[2] Panicker V, Saravanan P, et al. Common variation in the DIO2 gene predicts baseline psychological well-being and response to combination thyroxine plus triiodothyronine therapy in hypothyroid patients. J Clin Endocrinol Metab. 2009 May;94(5):1623-9.
[3] Benvenga S, Bartolone L, Pappalardo MA, Russo A, Lapa D, Giorgianni G, Saraceno G, Trimarchi F. Altered intestinal absorption of L-thyroxine caused by coffee. Thyroid. 2008 Mar;18(3):293-301.
[4] Presented at the American Academy of Anti-aging Medicine Module I Fellowship training (personal notes)
[5] http://en.wikipedia.org/wiki/Goitrogen
[6] Yorita Christensen KL. Metals in blood and urine, and thyroid function among adults in the United States 2007-2008. Int J Hyg Environ Health. 2012 Oct 5. pii: S1438-4639(12)00108-3.
[7] Chen A, Kim SS, Chung E, Dietrich KN.Thyroid hormones in relation to lead, mercury, and cadmium exposure in the National Health and Nutrition Examination Survey, 2007-2008. Environ Health Perspect. 2013 Feb;121(2):181-6.
[8] Re RN, Kourides IA, Ridgway EC, Weintraub BD, Maloof FThe effect of glucocorticoid administration on human pituitary secretion of thyrotropin and prolactin. J Clin Endocrinol Metab. 1976 Aug;43(2):338-46.
[9]Ch’ng CL, Jones MK, Kingham JG. Celiac disease and autoimmune thyroid disease. Clin Med Res. 2007 Oct;5(3):184-92.
[10] Fasano A (2001) Pathological and therapeutic implications of macromolecule passage through the tight junction. In Tight Junctions. CRC Press, Inc, Boca Raton, pp 697–722.
[11] Yu QH, Yang Q (2009) Diversity of tight junctions (TJs) between gastrointestinal epithelial cells and their function in maintaining the mucosal barrier. Cell Biol Int 33:78–82.
[12] Fasano A (2001) Intestinal zonulin: open sesame! Gut 49:159–162.
[13] Ventura A, Neri E, Ughi C, Leopaldi A, Città A, Not T.Gluten-dependent diabetes-related and thyroid-related autoantibodies in patients with celiac disease. J Pediatr. 2000 Aug;137(2):263-5.
[14] Chesney, A. M., Clawson, T. A., Webster, B.  Endemic goitre in rabbits. I. Incidence and characteristics. Bull. Johns Hopk. Hosp. 1928; 43:261.
[15] Greer, M. A., Astwood, E. B. The antithyroid effect of certain foods in man as determined with radioactive iodine. Endocrinology 1948, 43, 105.
[16] NIH office of Dietary Supplements Fact Sheet at: http://ods.od.nih.gov/factsheets/Iodine-HealthProfessional/
[17] NIH office of Dietary Supplements Fact Sheet at: http://ods.od.nih.gov/factsheets/Iodine-HealthProfessional/
[18] Tamer G, Arik S, Tamer I, Coksert D. Relative vitamin D insufficiency in Hashimoto’s thyroiditis. Thyroid. 2011 Aug;21(8):891-6.
[19] Saker KE, Fike JH, Veit H, Ward DL. Brown seaweed- (Tasco) treated conserved forage enhances antioxidant status and immune function in heat-stressed wether lambs. J Anim Physiol Anim Nutr (Berl). 2004 Apr;88(3-4):122-30.
[20] Duthoit C, Estienne V, Giraud A, Durand-Gorde JM, Rasmussen AK, Feldt-Rasmussen U, Carayon P, Ruf J. Hydrogen peroxide-induced production of a 40 kDa immunoreactive thyroglobulin fragment in human thyroid cells: the onset of thyroid autoimmunity? Biochem J. 2001 Dec 15;360(Pt 3):557-62.
[21] Skibola CF, Curry JD, VandeVoort C, Conley A, Smith MT. Brown kelp modulates endocrine hormones in female sprague-dawley rats and in human luteinized granulosa cells. J Nutr. 2005 Feb;135(2):296-300.
[22] Skibola CF. The effect of Fucus vesiculosus, an edible brown seaweed, upon menstrual cycle length and hormonal status in three pre-menopausal women: a case report. BMC Complement Altern Med. 2004 Aug 4;4:10.
[23] Radovic B, Schmutzler C, Kohrle J. Xanthohumol stimulates iodide uptake in rat thyroid-derived FRTL-5 cells. Mol Nutr Food Res. 2005 Sep;49(9):832-6.
[24] Laurberg P. Forskolin stimulation of thyroid secretion of T4 and T3. FEBS Lett. 1984 May 21;170(2):273-6.
[25] Panda S, Kar A. Changes in thyroid hormone concentrations after administration of ashwagandha root extract to adult male mice. J Pharm Pharmacol. 1998 Sep;50(9):1065-8.
[26] Panda S, Kar A. Withania somnifera and Bauhinia purpurea in the regulation of circulating thyroid hormone concentrations in female mice. J Ethnopharmacol. 1999 Nov 1;67(2):233-9.
[27] van der Hooft CS, Hoekstra A, Winter A, de Smet PA, Stricker BH. Thyrotoxicosis following the use of ashwagandha. Ned Tijdschr Geneeskd. 2005 Nov 19;149(47):2637-8.
[28] Panda S, Kar A. Gugulu (Commiphora mukul) induces triiodothyronine production: possible involvement of lipid peroxidation. Life Sci. 1999;65(12):PL137-41.
[29]Steiner M, Priel I, Giat J, Levy J, Sharoni Y, Danilenko M. Carnosic acid inhibits proliferation and augments differentiation of human leukemic cells induced by 1,25-dihydroxyvitamin D3 and retinoic acid. Nutr Cancer. 2001;41(1-2):135-44.
[30] Danilenko M, Wang X, Studzinski GP. Carnosic acid and promotion of monocytic differentiation of HL60-G cells initiated by other agents. J Natl Cancer Inst. 2001 Aug 15;93(16):1224-33.

Dr. Michael Cutler

By Dr. Michael Cutler

Dr. Michael Cutler is a graduate of Tulane University School of Medicine and is a board-certified family physician with more than 20 years of experience. He serves as a medical liaison to alternative and traditional practicing physicians. His practice focuses on an integrative solution to health problems. Dr. Cutler is a sought-after speaker and lecturer on experiencing optimum health through natural medicines and founder of the original Easy Health Options™ newsletter — an advisory on natural healing therapies and nutrients. His current practice is San Diego Integrative Medicine, near San Diego, California.