What Are the Signs of a Poor T4 Converter?

The thyroid gland is a small gland in the front of your neck that secretes hormones affecting all of your body's cells. A variety of health conditions are associated with an abnormally functioning thyroid gland. One problem your doctor may look for is your body's inability to convert the hormone T4 to the hormone T3. This can produce a variety of symptoms and illnesses. Understanding the causes of poor T4 conversion is an important step in treating your symptoms.

Abnormal Liver Function

• Your liver is responsible for the conversion of 60 percent of your T4 cells. If you have abnormal liver function, this will interfere with your body's ability to convert T4 to T3.

Abnormal Gastrointestinal Function

• Your gastrointestinal tract may contain microorganisms that interfere with your ability to convert T4 to T3. Twenty percent of your T4 cells undergo conversion in your gastrointestinal tract.

Decreased Selenium Level

• Selenium is a mineral consumed through the food you eat. It becomes a component of certain enzymes and helps your thyroid function normally. Inadequate selenium levels can be due to your diet or certain illnesses. Low levels of selenium can interfere with the normal conversion of T4 to T3.

Increased Cortisol Level

• Cortisol is a hormone produced by your body. It is released when your body is under stress. Increased stress will cause an increased cortisol level. An increased cortisol level interferes with normal T4 conversion. Your cortisol level can be checked with a laboratory blood test.

Signs of Hypothyroidism

• Signs of hypothyroidism can be present for a variety of reasons. One reason is poor T4 conversion. Symptoms of hypothyroidism include weakness, fatigue, weight gain, constipation, thinning hair or dry skin. If symptoms are present, your doctor should order various thyroid laboratory tests, to rule out T4 conversion problems.