TSH Levels – High, Low, Normal

TSH refers to Thyroid Stimulating hormones which are secreted by the thyroid gland.

The thyroid gland can be found in the lower end of the neck a little below the Adam’s apple. The organ is a vital component of the endocrine system and comprises of two lobe-like structures, each of which are located on the opposite sides of the trachea. The lobes of the thyroid gland are attached to the gland via the thyroid tissue called isthmus.

The thyroid gland performs the essential function of regulating and controlling the iodine levels in the body. Iodine gets an entry into the body via the intake of different kinds of food items, which is then turned into two major forms of TSH by the thyroid gland. They are known as T3 or tri-iodothyronine and T4 or thyroxine. Even though T4 is an important hormone, it is generally inactive within the body. Therefore, it is converted into the tri-iodothyronine hormone.

TSH or the thyroid stimulating hormones consisting of T3 and T4 are essential for the health of the body due to its involvement in different bodily functions, which include preserving the optimum levels of calcium within the body, regulating the body temperature and also controlling the various metabolic actions in eth body. When the TSH levels are higher or lower than the normal required levels, then the overall health of the body can be seriously affected.

The production and regulation of the TSH levels is carried out by the thyroid gland in conjunction with the pituitary gland and the hypothalamus. A disturbance in the equilibrium that exists between these 3 glands can lead to the production of abnormal levels of TSH, which ultimately result in extreme medical complications. It has to be noted that women are generally more susceptible to variations in the TSH levels as compared to men.

Normal TSH levels

• The TSH levels in the body are measured in terms of mlU/L, i.e. milli-international units per liter
• The normal TSH levels in both men and women are said to range from 0.5 mIU/L to 4.5 mIU/L.
• The normal TSH levels in children are generally higher, with normal infant TSH levels ranging from 3 mIU/L to 18 mIU/L

It is important to note that women who decide to become pregnant, or are already expectant mothers, have to be continuously aware of the TSH levels during the different stages of pregnancy. Abnormal TSH levels can result in several complications for the unborn baby as well as the expectant mother, like premature delivery of the baby.

It is also vital to be aware of the fact that normal TSH levels in women with autoimmune conditions need not necessarily cause a difference during pregnancy. The presence of such disorders can also lead to premature delivery.

The normal TSH levels during pregnancy and classified as per the different trimesters are listed below:

• The normal TSH levels in women during the first trimester of pregnancy ranges between 0.25 mIU/L and 2.96 mIU/L
• The normal TSH levels in women during the second trimester of pregnancy ranges between 0.45 mIU/L and 2.94 mIU/L
• The normal TSH levels in women during the third trimester of pregnancy ranges between 0.42 mIU/L and 2.76 mIU/L

High and low TSH levels

• Lower than normal levels of TSH production can result in a condition called hypothyroidism
• Higher than normal levels of TSH production can result in a condition known as hyperthyroidism

Symptoms of hypothyroidism

The symptoms of hypothyroidism in men and women may be seen as abnormalities of the physical, cognitive or digestive systems. They include:

• Physical aspects:
  • Muscle weakness which may be experienced as stiffness, tenderness and muscle aches
  • Voice quality changes like deeper or hoarser voice
  • Increased weight
  • Easy tiredness or exhaustion
  • Puffed up eyes
  • Wrist pain and joint pains along with stiffness and swelling
  • Numbness of the hands
  • High blood cholesterol levels
  • The skin may elicit a pale complexion along with increased dryness and coarseness
  • Abnormal menstrual periods in women, such as heavy or absent menstruation
  • A lowered rate of metabolism may lead to high sensitivity to cold as well as hair loss
  • Shivers and trembling
  • Immune system anomalies
  • Cognitive aspects:
    • Nervousness and Depression
    • Diminished intellectual capacities, leading to loss of memory, forgetfulness and even dementia
    • Digestive aspects:
      • Discharge of abnormal stool
      • Poor appetite or loss of appetite
      • Constipation

Symptoms of hyperthyroidism

The initial symptoms of hyperthyroidism are gentle and generally tend to worsen with the progression of the disease. The symptoms include the following:

• Poor or abnormal menstrual discharge in women
• The upper eyelids in women may become raised giving rise to a distinct stare or look. Additionally, puffy eyes may be observed
• Increased fatigue
• Persistent bowel movements
• Increased rate of heart beats
• Loss in weight
• Tremors
• Increased perspiration
• Irritability or inattentiveness

Treatment of abnormal TSH levels

• Hypothyroidism is treated with a lifetime of thyroid hormone replacement therapy. Additionally, lifestyle changes such as dietary changes, regular exercise and intake of nutritional supplements is also recommended
• Hyperthyroidism is treated with anti-thyroid medicines or oral radioactive iodine. Extreme instances of the disease may require surgical removal of the thyroid gland.