Thyroid Levels: Symptoms of Low Thyroid

Thyroid gland is a small butterfly shaped gland, situated just below the larynx (voice box) or 'Adams apple' and is a significant part of the endocrine system. It consists of two lobes lying on either side of the trachea, joined together by thyroid tissue called 'isthmus'. The function of the thyroid gland is to convert the iodine from the food into two main thyroid hormones: thyroxine (T4) and triiodothyronine (T3). T4 is the main hormone produced by the thyroid gland, however, it is inactive and has to be converted to T3. These thyroid hormones are essential for regulation of body metabolism, temperature regulation, maintaining calcium balance and overall growth and development of the body. Thyroid gland is controlled by a pea sized endocrine organ in the brain called the pituitary gland (master gland), which is itself regulated by the hypothalamus (part of the brain).

Thyroid levels

When the levels of T4 and T3 in the blood fall, the hypothalamus releases 'thyroid releasing hormone' (TRH) into the bloodstream. As the level of TRH in the blood increases, the pituitary gland gets the signal from the hypothalamus, and as a result releases 'thyroid stimulating hormone' (TSH). TSH stimulates the thyroid gland to produce and release more hormone into the blood. However, if the thyroid hormone levels in the blood are high, the hypothalamus stops releasing TRH. The pituitary gland picks up the low TRH signal and stops releasing TSH, thereby regulating the level of thyroid level in the bloodstream. Thus, its a link between the hypothalamus, pituitary gland and the thyroid gland, all working in co-ordination with one another.

According to most laboratories in the US, the normal level of TSH that should be present in the bloodstream ranges from 0.5-5.0 mIU/L. The thyroid levels can be determined by performing the 'T7' or 'FTI' blood test. For any reason, if the thyroid levels deflect from this range, then there is cause for concern. High thyroid levels in the bloodstream is a disorder termed as hyperthyroidism, whereas, low thyroid level is termed as hypothyroidism. Hypothyroidism is more common as compared to hyperthyroidism.

Low Thyroid Level/ Hypothyroidism

Hypothyroidism is a disorder caused due to formation of less thyroid hormone in comparison to the normal body requirements, and the thyroid gland is called to be 'under active'. Inadequate thyroid hormones results into slowing down of the overall body metabolism. Hypothyroidism affects both men and women, however, women are eight times more susceptible. People of all ages can be affected and over 5 million Americans have this disorder. Hypothyroid people are susceptible to heart disorders, cancers and infections. Severe hypothyroidism in adults is called 'Myxedema' and in children it is called 'Cretinism'.

Hashimoto's disease (inflammation of the thyroid gland) is one of the major reasons for low thyroid levels. This is an autoimmune disease wherein the body fails to recognize the thyroid gland as its own member and begins to attack it with antibodies, as if it is a foreign body. This not only damages the gland's 'hormone releasing capacity' but also destroys the gland. Iodine deficient diets, malfunctioning of the pituitary gland or hypothalamus, infection of the thyroid gland, radiation treatments to treat hyperthyroidism and congenital defects are some other reasons responsible for low thyroid levels. Birth control pills are also harmful for the thyroid gland as estrogen inhibits the gland's activity.

Symptoms of Low Thyroid:

'Silent disease' is another name given to hypothyroidism because it reveals itself in a very gradual manner. Maximum number of people fail to recognize this disorder. They cannot be blamed for this as symptoms of this disease are very subtle, and to make matters worse are often similar to the ones of aging. The severity of the hormone deficiency determines the extent of the symptoms. Low thyroid levels affect different parts of the body in different ways.

• Overall symptoms: Since thyroid hormone is responsible for regulation of body metabolism, its deficiency results in slowing down of body's metabolic processes. The person suffering from this disorder encounters fatigue, tiredness, sluggishness, weakness, insomnia, dementia, lack of concentration, depression, muscle cramps, cold intolerance and weight gain (usually 5 to 10 pounds).
• Skin: Low thyroid level reduces sweating rate and causes the skin to become dry, coarse and thick. Sometimes a yellowish hue to the skin is also observed. The nails become brittle, eyebrows fall off, and hair loss occurs.
• Gastrointestinal System: The muscles used for digestion slow down, resulting into constipation.
• Cardiovascular System: The functions of the heart slow down. The person can get easily tired and breathless while exercising, etc. Increased heart rate and palpitations are common. Cholesterol levels in the blood are also seen to rise. For hypertensive people, the severity of the symptoms may be far greater. The stimulation of red blood cells in the bone marrow becomes inadequate resulting into anemia.
• Face: Puffiness of the face, especially the areas around the eyes.
• Reproductive System: In case of women, low thyroid levels lead to irregularities in the menstrual cycle. The irregularities vary from no periods to heavy, frequent periods. Infertility makes conceiving impossible. In case of pregnant women, the deficiency increases the risk of miscarriage during early stages of pregnancy.
• Respiratory System: Respiratory muscles become weak causing frequent breathlessness and fatigue. Frequent blockage of the air passages while sleeping hinders the person from having a good night sleep. Insomnia, hoarse voice are some other symptoms.

Simple and effective medical treatment is available for curing low thyroid levels. Hypothyroidism once diagnosed, is curable and most people begin to feel better in a week or two of treatment. The relieving part is that all the symptoms of this disorder disappear for good within a few months of time, allowing the sufferers to resume their routine-active lives once again!