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What is Triiodothyronine (T3)?

Thyroid hormone triiodothyronine (T3) controls the body’s metabolic rate, heart and digestive functions, muscle regulation, brain growth and function, and bone maintenance, among other functions. The thyroid gland secretes approximately 20% of triiodothyronine directly into the bloodstream. The remaining 80% is produced from the conversion of thyroxine by organs such as the liver and kidneys.

What happens if I have too much triiodothyronine?

People who have too much triiodothyronine may suffer from a condition called thyrotoxicosis. This occurs when there is too much of the thyroid hormone circulating in the blood. This may occur by overactivity of the thyroid gland (hyperthyroidism), Grave’s disease, thyroid inflammation, and more. 

Other symptoms of thyrotoxicosis include heat intolerance, weight loss, increased appetite, increased bowel movements, irregular menstrual cycles, and many more.

What happens if I have too little triiodothyronine?

On the other hand, if there isn’t enough triiodothyronine, then a person may suffer from hypothyroidism. People with this condition may suffer from tiredness, intolerance to cold weather, low heart rate, weight gain, diminished appetite, impaired memory, depression, muscle stiffness, and reduced fertility.

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