Hashimoto’s thyroiditis is a prevalent autoimmune disorder that primarily affects the thyroid gland, leading to hypothyroidism, or an underactive thyroid. While the direct impact on thyroid function is well known, this condition also has broader metabolic implications, including effects on liver health. One of the significant challenges for individuals with Hashimoto’s is the potential for impaired lipid metabolism, which can result in fat accumulation in the liver, a condition now called metabolic dysfunction-associated steatotic liver disease (MASLD, formerly non-alcoholic fatty liver disease or NAFLD). Understanding this connection and the potential role of specific nutrients in supporting liver health is crucial for managing overall health in Hashimoto’s.
The Link Between Hashimoto’s and Liver Health
The thyroid gland produces hormones—mainly thyroxine (T4) and triiodothyronine (T3)—that are essential for regulating metabolism. In Hashimoto’s thyroiditis, the immune system attacks the thyroid, often leading to decreased production of these hormones. Even when T4 levels are managed with medication, the conversion of T4 to the more active T3 can be impaired. This impairment affects metabolism throughout the body, including in the liver.
T3 is critical for lipid metabolism, helping the body break down fats for energy. When T3 levels are low, the liver’s ability to process fats efficiently diminishes, which may contribute to fat accumulation in the liver. Large studies find more fatty liver the lower thyroid function is, and low thyroid function has also been linked with the more severe stages, steatohepatitis (NASH, now MASH) and fibrosis. These studies show an association; they do not prove that low thyroid function causes it.
How Impaired Thyroid Function Leads to Liver Fat Accumulation
- Reduced Metabolic Rate: With lower T3 levels, the body’s basal metabolic rate (BMR) decreases, leading to fewer calories being burned at rest and more being stored as fat.
- Impaired Lipid Metabolism: T3 is essential for lipid metabolism. When its levels are insufficient, the liver’s ability to metabolize lipids is compromised, leading to increased fat storage in the liver .
- Insulin Resistance: Hypothyroidism is often associated with insulin resistance, a condition where the body’s cells do not respond effectively to insulin. This can lead to increased fat accumulation in the liver, as insulin resistance increases the amount of free fatty acids in the bloodstream .
- Fatigue and Reduced Physical Activity: Fatigue, a common symptom of hypothyroidism, often leads to decreased physical activity, which further contributes to weight gain and fat accumulation.
Nutrients That Support Liver Health and Lipid Metabolism
While managing thyroid hormone levels is crucial, certain nutrients take part in fat metabolism in the liver. None of the four below has been tested in people with Hashimoto’s specifically; what is known comes from research on liver fat in general:
1. Choline
Choline is a vital nutrient for liver function, particularly in the transport of fats from the liver to other parts of the body. It is crucial for the synthesis of phosphatidylcholine, a component of very low-density lipoproteins (VLDL), which are responsible for exporting fats out of the liver. Choline contributes to normal lipid metabolism and to the maintenance of normal liver function, and a diet too low in choline leads to fat build-up in the liver.
Dietary Sources: Eggs, liver, fish, nuts, and cruciferous vegetables.
2. Inositol
Inositol, particularly myo-inositol, plays a significant role in insulin signal transduction, which is essential for maintaining insulin sensitivity. Improved insulin sensitivity can help reduce fat accumulation in the liver and support overall metabolic health. Additionally, trials combining myo-inositol with selenium have reported lower TSH in people with subclinical hypothyroidism and autoimmune thyroiditis. An effect on the conversion of T4 to T3 itself has not been established.
Dietary Sources: Fruit such as cantaloupe, oranges and other citrus, which supply free myo-inositol. Grains and legumes contain inositol too, but mostly bound as phytate, which the body absorbs poorly.
3. Methionine
Methionine is an essential amino acid. The liver turns it into SAMe, the main donor for methylation reactions, and, further along the same pathway, into cysteine, which is needed to make glutathione. In rodents, a diet lacking both methionine and choline causes fatty liver with inflammation; that extra methionine reduces liver fat in people has not been shown. Its role in producing glutathione, a potent antioxidant, helps protect liver cells from oxidative damage .
Dietary Sources: Meat, fish, dairy products, and plant-based sources like Brazil nuts and sesame seeds.
4. Taurine
Taurine is an amino acid that, in animal studies, promoted the oxidation of fatty acids and reduced fat accumulation in the liver. It is also used to form bile salts, which are needed for the digestion and absorption of dietary fats. Additionally, taurine’s antioxidant properties help protect the liver from oxidative stress in laboratory studies; trials in people with fatty liver are few.
Dietary Sources: Meat, fish, dairy products, and some energy drinks (though supplements are also available).
A Comprehensive Approach to Liver Health in Hashimoto’s
Whatever role these nutrients play, they should be considered part of a comprehensive approach to managing Hashimoto’s thyroiditis. This approach includes:
- Thyroid Hormone Management: Ensuring that thyroid hormone levels are appropriately managed through medication and regular monitoring.
- Balanced Diet: Incorporating a diet rich in these nutrients, along with other liver-friendly foods, can help support overall health.
- Physical Activity: Engaging in regular physical activity can help improve metabolic rate, enhance insulin sensitivity, and reduce fat accumulation.
- Medical Guidance: Consulting with healthcare providers or registered dietitians before starting any new supplements or making significant dietary changes is essential, especially for individuals with existing health conditions or those taking other medications. Never stop or change prescribed thyroid medication without your doctor.
Conclusion
Liver health is a crucial aspect of overall well-being, particularly for individuals with Hashimoto’s thyroiditis. By understanding the connection between impaired thyroid function and liver fat accumulation, and by paying attention to nutrients such as choline, inositol, methionine and taurine, individuals can take proactive steps to manage their health. As always, a comprehensive approach that includes medical management, dietary considerations, and lifestyle adjustments is key to achieving the best outcomes. If you take thyroid medication and would like to go over a supplement with your doctor first, the LiverGuard page lists every ingredient and dose, so you can bring it to your next appointment.
Sources:
- T3 and Lipid Metabolism: Sinha RA, Singh BK, Yen PM. Thyroid hormone regulation of hepatic lipid and carbohydrate metabolism. Trends in Endocrinology & Metabolism. 2014;25(10):538-545. doi:10.1016/j.tem.2014.07.001.
- Insulin Resistance and Hypothyroidism: Maratou E, Hadjidakis DJ, Kollias A, et al. Studies of insulin resistance in patients with clinical and subclinical hypothyroidism. European Journal of Endocrinology. 2009;160(5):785-790. doi:10.1530/EJE-08-0797.
- Choline and Liver Health: Corbin KD, Zeisel SH. Choline metabolism provides novel insights into non-alcoholic fatty liver disease and its progression. Current Opinion in Gastroenterology. 2012;28(2):159-165. doi:10.1097/MOG.0b013e32834e7b4b.
- Inositol and Insulin Sensitivity: Genazzani AD, Lanzoni C, Ricchieri F, Jasonni VM. Myo-inositol administration positively affects hyperinsulinemia and hormonal parameters in overweight patients with polycystic ovary syndrome. Gynecological Endocrinology. 2008;24(3):139-144. PMID: 18335328.
- Inositol and Thyroid Function: Nordio M, Pajalich R. Combined treatment with myo-inositol and selenium ensures euthyroidism in subclinical hypothyroid patients with autoimmune thyroiditis. Journal of Thyroid Research. 2013;2013:424163. doi:10.1155/2013/424163.
- Methionine, SAMe and Liver Health: Lu SC, Mato JM. S-adenosylmethionine in liver health, injury, and cancer. Physiological Reviews. 2012;92(4):1515-1542. doi:10.1152/physrev.00047.2011.
- Taurine and Liver Health: Miyazaki T, Matsuzaki Y. Taurine and liver diseases: a focus on the heterogeneous protective properties of taurine. Amino Acids. 2014;46(1):101-110. doi:10.1007/s00726-012-1381-0.
- NAFLD and Hypothyroidism: Chung GE, Kim D, Kim W, et al. Non-alcoholic fatty liver disease across the spectrum of hypothyroidism. Journal of Hepatology. 2012;57(1):150-156. doi:10.1016/j.jhep.2012.02.027.
- Thyroid Function, NASH and Fibrosis: Kim D, Kim W, Joo SK, et al. Subclinical hypothyroidism and low-normal thyroid function are associated with nonalcoholic steatohepatitis and fibrosis. Clinical Gastroenterology and Hepatology. 2018;16(1):123-131.e1. doi:10.1016/j.cgh.2017.08.014.
