Thyroid-stimulating hormone (TSH) prompts the thyroid gland to increase hormone production.
Your body uses TSH to control thyroid hormone levels.
In response, the pituitary gland sends TSH to the thyroid gland.
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As a result, thyroid hormones return to optimal levels.
High thyroid hormones stop the hypothalamus from sending thyrotropin-releasing hormones.
The thyroid gland continues producing the same amount of thyroid hormones until blood levels fall to an acceptable level.
TSH Levels
YourTSH levelsmay be high or low.
Both can be natural and acceptable, depending on the body’s current thyroid hormone needs.
Some labs use varying ranges or measurements when doing a TSH test.
High TSH
Your TSH levels should be high if your thyroid hormones are low.
Thyroid hormones naturally fluctuate during the day, causing changes in TSH levels.
However, consistently high TSH may mean you have an underactive thyroid (hypothyroidism).
Though rare, the pituitary gland may develop a tumor that actively produces TSH.
In that case, your TSH levels will rise above the healthy range and trigger excessive thyroid hormone production.
Low TSH
Your TSH levels should be low when your thyroid hormones are too high.
In the event TSH levels remain persistently low, you may have an overactive thyroid (hyperthyroidism).
The hormones made in your thyroid gland are essential to your metabolism, growth, and development.
Thyroid Conditions
Conditions that affect the thyroid gland also cause fluctuations in TSH levels.
Some conditions, like nodules, may cause either hypothyroidism or hyperthyroidism.
Iodine and Thyroid Hormones
Iodineis essential for the production of the thyroid hormones.
A few sources include fish, dairy products, eggs, and iodized salt.
Symptoms
The symptoms you experience don’t necessarily reflect TSH levels.
They’re signs of hypothyroidism or hyperthyroidism.
Hypothyroid Treatments
Treating an underactive thyroid focuses on medications to restore normal thyroid levels.
This typically means thyroid replacement therapy usinglevothyroxinemedicines like Levo-T and Synthroid.Your symptoms improve as hormonal balance is restored.
If you have hypopituitarism (an underactive pituitary gland), you’ll need hormone replacement medications.
Summary
Thyroid-stimulating hormone (TSH) triggers the production of thyroid hormones.
When thyroid hormone levels fall, the pituitary gland sends TSH to the thyroid gland.
TSH activates the gland to increase its production of thyroid hormones, which boosts blood levels back to normal.
TSH levels naturally fluctuate depending on whether the body needs to raise or lower thyroid hormone levels.
Your healthcare provider will determine the problem and recommend treatment to restore hormonal balance.
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