TBG

Thyroxine Binding Globulin

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What's

TBG

Thyroxine Binding Globulin (TBG) is a special protein made by your liver that helps your body in a very important way. Think of it like a delivery service for your thyroid hormones, thyroxine (T4) and triiodothyronine (T3). TBG attaches to these hormones in your blood and carries them to different parts of your body. When they arrive at their destination, the hormones are released and start working to control your metabolism. This affects everything from how much energy you have to how warm you feel. In short, TBG makes sure your thyroid hormones are safely and effectively taken where they're needed most.

If Your Levels Are High

Elevated TBG levels might mean that your body is making more of this protein than usual. This can happen for various reasons, such as changes in hormone levels, especially increased estrogen, which can happen during pregnancy or from taking certain medications like birth control pills or hormone replacement therapy. Liver disease could also lead to higher TBG levels, since your liver is in charge of making this protein. It's important to remember that genetics can play a part too, as some people naturally have higher TBG levels. So, high levels could be due to hormonal changes, specific medications, liver issues, or even just your genetic makeup.

Symptoms of High Levels

Symptoms of high levels of TBG may not be directly noticeable, as TBG itself doesn't cause symptoms. However, if the increase in TBG is due to an underlying condition, such as liver disease or hormonal changes, symptoms related to those conditions might be present. These could include fatigue, unexplained weight changes, sensitivity to cold or heat, and changes in heart rate.

If Your Levels are Low

Low TBG levels might mean that your body isn't making enough of this important protein, which helps carry thyroid hormones to different parts of your body. This could be due to various reasons, such as not getting enough nutrients, having liver problems, or inheriting certain genetic conditions. Some medications, like steroids or birth control pills, could also potentially lower TBG levels. When there's not enough TBG, your thyroid hormones might not be transported as effectively, which could affect how your body functions, like managing your energy levels and keeping you warm.

Symptoms of Low Levels

Symptoms of low levels of TBG may include fatigue, unexplained weight gain, feeling cold, dry skin, and hair loss.

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