Low Thyroid: What is it? Causes, Symptoms, Diagnosis and Treatment

This gland is a butterfly-shaped organ found in the center of the neck.

It creates and stores hormones that control the body’s heart rate , blood pressure, and metabolism (how the body produces energy from food).

Low thyroid is when the thyroid gland is underactive and does not release thyroid hormones necessary for human metabolism.

The thyroid gland normally releases necessary hormones that are transported through the bloodstream to receptors located throughout the body.

The alteration in thyroid function causes health problems.


Low thyroid causes include:

Inflammatory thyroid disorders

The most common cause of low thyroid in adults is Hashimoto’s thyroiditis, which causes long-term inflammation of the thyroid gland .

This disease damages the thyroid tissue so the gland cannot function properly.

When the patient has Hashimoto’s thyroiditis, the body itself essentially begins to attack itself by producing antibodies that attempt to destroy the thyroid gland.

Diet deficient in iodine and selenium.

A low intake of nutrient-rich foods, and a deficient intake of iodine and selenium.

These are essential minerals for thyroid function and increase the risk of thyroid gland disorders.

These nutrients also play other protective roles in the body.

For example, severe selenium deficiency increases the incidence of thyroiditis because it stops the activity of a very powerful antioxidant known as glutathione, which normally controls inflammation and combats oxidative stress.

Hormonal imbalances

In some rare cases, the pituitary gland, which produces thyroid stimulating hormone, can cause changes in the levels of hormones in thyroid function.

Leaky gut syndrome or intestinal-type poisoning

Food sensitivities or allergies, including those related to gluten and dairy, can trigger intestinal inflammation.

Among other causes that can cause intestinal problems are stress levels, an excess of toxins in the diet and the environment and imbalances produced by bacteria.

When leaky gut occurs, small particles that normally get trapped within the gut begin to leak into the bloodstream through tiny openings in the intestinal lining, creating an autoimmune cascade and a host of negative symptoms.


Although it is not very common, babies are sometimes born with a genetic condition called congenital hypothyroidism, caused by a dysfunction of the thyroid gland.

Some tests show that people are more likely to develop a low thyroid if they have a close family member with an autoimmune disease.


Although the exact cause is not known, some women produce very high levels of thyroid hormones, followed by a very rapid drop in thyroid hormone levels when they are pregnant.

Causing a condition called postpartum thyroiditis .

Symptoms often go away in 12 to 18 months, but they can also lead to permanent hypothyroidism.

Interactions of certain medications

Specific medications appear to frequently lead to the development of an underactive thyroid.

The most common include drugs to treat cancer, heart problems, and certain psychiatric conditions.

High levels of emotional stress

The stress affects hormones and is known to worsen inflammation.

Stress can raise cortisol and adrenaline levels, disrupting neurotransmitter function and worsening thyroid disease symptoms.

These include low energy levels, bad mood, low concentration, impaired appetite, and weight gain, as well as the inability to get a good night’s sleep.

Symptoms of a low thyroid

The thyroid gland has been considered a “master gland.”

In addition to having the function of producing important hormones, it also helps to control the metabolic process, supporting the conversion of nutrients that are present in food, into useful energy for the maintenance of the body, and the ability to burn calories.

These hormones produced by the thyroid are key in the breakdown of cholesterol, controlling the levels of triglyceride fat that circulates through the bloodstream.

For this reason the changes that occur in thyroid function are the cause of heart problems.

One of the notable effects of a low thyroid includes mood swings accompanied by states of depression and anxiety, poor sleep and low immunity, and slowing down of metabolism, which result in fatigue and weight problems.

A myxedematous coma, caused by a low thyroid, is characterized by a decreased mental state of the patient, hypothermia, and slowing of various organs.

Thyroid nodules are an accumulation of cells within the thyroid, creating an atypical mass.

Thyroid nodules are not usually dangerous, but they may turn cancerous over time.

Other symptoms that may occur are:

  • Sterility.
  • Feeling cold
  • Constipation.
  • Muscle pains.
  • Stiffness and inflammation in the joints.
  • Hair loss.
  • Cracked and rough-looking skin.
  • Trouble breathing.
  • Changes in the length of the menstrual cycle.
  • Cold or flu are more common due to low immune function.

Low thyroid, if left untreated, can become a very dangerous condition.


There are a number of thyroid tests that can be done to get a better idea of ​​what’s going on in the thyroid: common blood tests for thyroid-stimulating hormone, T4, T3, TPO, and reverse T3.

In general, thyroid stimulating hormone levels less than 0.3 mIU / L and free T3 levels less than 2.0 mg / dl can indicate thyroid problems.

In addition to these tests, you can consider the following subclinical hypothyroidism self test, basically low thyroid that will not be detected in a blood test.

Every morning, the body temperature is taken. Normal body temperature at rest taken in the morning is between 36.56ºC and 36.78ºC.

The normal active temperature taken during the day should be 37 ºC. If the average of the three daily readings, in the morning, over a 10-day period, falls below 37 ° C, then a low thyroid function may be suspected.

Low thyroid treatment

Low thyroid is usually treated, at least medically, with T4 medications like Synthroid.

However, there are many parts of the thyroid “chain” that can be broken and therefore must be addressed.

For example, since T4 is converted to T3 (the active form of thyroid hormone) in the liver and intestine, it is crucial to ensure optimal health in both areas.

Furthermore, 90% of low thyroid cases are autoimmune in nature (Hashimoto), which means that correcting the ultimate source of the problem (leaky gut) will be very important.

The thyroid can be helped with a good combination of nutrients such as iodine, selenium, zinc, and N-Acetyl-L-Tyrosine.

For patients with thyroid cancers, a common conventional treatment method is known as radioactive iodine.

Because the thyroid absorbs most of your body’s iron content, this concentrated radiation is supposed to successfully kill most diseased thyroid cells without damaging cells in the rest of the body.

Exercise and a healthy diet are vital to managing stress and neurological function that is related to hormone secretion.

Research shows that people who exercise regularly tend to sleep better, cope better with stress, and more often maintain a healthier weight, reducing some of the biggest risk factors and symptoms associated with a low thyroid.