Low thyroid levels

The thyroid gland is one of the largest endocrine glands in the body. It is positioned in the neck, below the thyroid cartilage, or the Adam’s apple, and at the same level as the cricoid cartilage. The thyroid gland plays an important role in a couple of essential bodily processes, such as making proteins, determining the rate at which the body uses energy, and controlling the sensitivity to other hormones.

Low production of thyroid hormones, T3 and T4, is medically known as hypothyroidism. Hypothyroidism occurs as a result of an inactive or under-active thyroid gland and includes a great number of symptoms. This condition is very common, and it is estimated that approximately 10 million Americans suffer from low thyroid levels. Thyroid abnormalities are more common in women, and as many as 10% of all women seem to have some sort of thyroid deficiency.

Signs and Symptoms of Hypothyroidism

Hypothyroidism includes a wide range of possible symptoms. The number of symptoms and their severity depends on the severity of the thyroid deficiency. In some patients, one symptom will be dominant, while the others may appear in milder forms, or not appear at all. However, there is a significant portion of completely asymptomatic patients in which this disorder may go unnoticed.

Symptoms of low thyroid levels include tiredness, excessive weight gain, dry hair and skin, hair loss, inability to tolerate colds, muscle cramps, problems with digestion, lower cognitive functions, depression, irritability, memory loss, abnormal menstrual cycles, and decreased sexual desire.

Causes of Hypothyroidism

Low thyroid levels are most commonly caused by one of the two predominant health conditions. The first condition is known as Hashimoto’s thyroiditis. In this condition, hypothyroidism results from a previous inflammation of the thyroid gland. This leaves the cells of the thyroid gland dead or damaged, and incapable of producing sufficient levels of hormone.

The second most probable cause of hypothyroidism is iodine deficiency. The body is unable to synthesize iodine and must get it from the daily diet. Iodine is an element that is essential for the production of thyroid hormone. Iodine deficiency can lead to the enlargement of the thyroid gland or even mental retardation in infants and children whose mothers were iodine deficient during pregnancy.

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the leading cause of chronic liver diseases worldwide, affecting approximately 30% of the global adult population. MAFLD is a nomenclature that captures fatty liver disease (FLD) with metabolic dysfunctions. A previous study showed that the long-term complications of MAFLD have made it the most common cause of liver transplantation. The etiology of MAFLD involves complex factors, such as obesity, hepatitis C infection, and diabetes. Thyroid function has been proposed as one of the most important risk factors for its prominent effects on hepatic fatty acid and cholesterol synthesis.

Thyroid hormones play a critical role in maintaining metabolic homeostasis throughout life and are intimately linked to the liver. Normal thyroid function is essential for maintaining liver metabolism; while thyroid disorders affect the clinical progression of liver disease.
Observational studies showed that low thyroid function may perturb liver function. We aimed to evaluate the association of low thyroid function with both metabolic dysfunction-associated fatty liver disease (MAFLD) and advanced hepatic fibrosis.
Participants who underwent abdominal ultrasonography and thyroid function test in a Chinese hospital from 2015 to 2021were enrolled. Fibrosis-4 index (FIB-4)?>?2.67 and/or non-alcoholic fatty liver disease fibrosis score (NFS)?>?0.676 were used to define advanced fibrosis. Descriptive analyses were performed to characterize the epidemiology of MAFLD according to levels of thyroid-stimulating hormone (TSH). The logistic regression model was applied to estimate the association of low thyroid function with MAFLD and advanced fibrosis.
A total of 19,946 participants (52.78% males, mean age: 47.31 years, 27.55% MAFLD) were included, among which 14,789 were strict-normal thyroid function, 4,328 were low-normal thyroid function, 829 were subclinical hypothyroidism. TSH levels were significantly higher in MAFLD patients with a FIB-4?>?2.67 and /or NFS?>?0.676 than their counterparts.
The logistic regression model adjusted for age and sex showed that low-normal thyroid function increased the risk of MAFLD (odds ratio [OR]?=?1.09; 95% confidence interval [CI] 1.01–1.18). Multivariable regression model adjusted for age, sex, body mass index, type 2 diabetes, and hypertension showed low-normal thyroid function increased the risk of advanced fibrosis in patients with MAFLD (FIB-4?>?2.67: OR?=?1.41, 95% CI 1.02–1.93; NFS?>?0.676: OR?=?1.72, 95% CI 1.08–2.72).

✓ Fact confirmed: Low thyroid function is associated with an increased risk of advanced fibrosis in patients with metabolic dysfunction-associated fatty liver disease Hong Fan, Lili Li, Zhenqiu Liu, Pengyan Zhang, Sheng Wu, Xinyu Han, Xingdong Chen, Chen Suo, Liou Cao & Tiejun Zhang; 05 January 2023

Treatment of Low Thyroid Levels

Persons who have been experiencing symptoms of hypothyroidism should consult a doctor and get a thyroid blood test. In treatment of hypothyroidism, doctors usually prescribe synthetic thyroxine pills as a substitute for normal thyroid hormone. If the condition develops as an effect of iodine deficiency, the patient will be advised to include foods rich in iodine and selenium in the daily diet.