Low TSH Symptoms

TSH, or thyroid stimulating hormone, activates the thyroid gland and regulates the release of thyroid hormones T3 and T4. The anterior pituitary gland releases TSH which in turn controls the release of thyroid hormones.

As the name suggests, the function of the TSH is to stimulate the thyroid gland. So, when thyroid becomes hyperactive and starts producing excess T3 and T4, the pituitary gland releases less TSH. A hyperactive thyroid is the main and common cause of low TSH.

As per the revised American standards, TSH levels between 0.3 to 3.3 mIU/L (milli-international units per liter) are considered as normal. However, some labs still consider the normal TSH levels for reference as per old standards, between 0.5 to 5.5 mIU/L.

Some labs consider 0.4 - 4.0 mIU/L as normal TSH levels. But according to the revised scale, TSH level less than 0.3 mIU/L indicates hyperthyroidism and TSH level greater than 3.0 mIU/L indicates hypothyroidism (an under-active thyroid). To stimulate an under-active thyroid, pituitary gland releases more TSH.

Lowering of TSH levels is body's natural response towards hyperactive thyroid. If the levels drop down abnormally, doctors prescribe medications to bring them back to normal levels. Sometimes, the pituitary gland fails to release more TSH even though the body is experiencing hypothyroidism.

Low TSH levels during hypothyroidism are considered as abnormal. A pituitary problem or a hypothalamus disorder can cause low TSH levels. A tumor in the head can affect pituitary or hypothalamus function.

The hypothalamus from the brain produces the hormone 'thyrotropin' which controls the function of the anterior pituitary gland and in turn, the production of thyroid stimulating hormone (TSH).

Another hormone 'somatostatin', produced by the hypothalamus acts as the antagonist of the hormone 'thyrotropin'. Imbalance of these two hormones can lead to abnormal TSH levels. Diseases and disorders like Hashimoto's thyroiditis, Grave's disease, can affect TSH levels severely.

Since low TSH normally indicates hyperthyroidism, low TSH symptoms include:

• Heat intolerance
• Profuse sweating leading to weakness
• Impotence in men
• Increased bowel movements owing to the increased rate of metabolism
• Rapid heart rate

• Agitation, nervousness and tremor
• Increased anger, irritability
• Sudden attacks of nervousness
• Increased appetite

• Weight loss despite increased appetite
• Decreased concentration
• Fatigue
• Hot flashes, joint pain in women
• Difficulty in sleeping
• Light and less frequent menstrual periods
• Low bone density
• Rapid peristalsis, fast movement (wavelike) of the alimentary tract muscles leading to fast movement of the food

In case of hyperthyroidism, anti-thyroid drugs are prescribed to slow down the thyroid activity. Proper use of medication helps cancel the effect of excess T3 and T4 on the tissues.

Depending upon the severity of the symptoms, surgical removal of some part of the thyroid gland is sometimes helpful. The treatment varies according to the cause, severity of the condition and age of the patient.

Low TSH levels can be raised with the help of regular exercise. Practicing yoga, meditation and breathing exercises like Pranayama helps enhance the function of the pituitary gland.

In general, regular exercises help improve the functions of the endocrine and exocrine glands in the body. They help maintain the normal weight and stable mind, preventing hormonal imbalance and various health complications.

The doctor may help plan a healthy thyroid diet after checking the symptoms. Iodine and selenium in diet play an important role in maintaining the thyroid function. Severe fluctuations in blood sugar levels affect the functions of the glands.

So maintaining normal blood sugar level with the help of balanced diet and regular exercise helps maintain TSH and thyroid levels. If you notice low TSH symptoms, you should check all these factors and modify your diet and lifestyle accordingly.