Normal Thyroid TSH Range

The thyroid is a gland in your neck that produces hormones to keep your body going, affecting growth, metabolism, temperature and energy level. You feel the adverse effects when it produces too much or too little of the hormones.

Hormone Basics

• The thyroid's main purpose is to produce two hormones, thyroxine (T4) and triiodothyronine (T3). The pituitary gland makes TSH, or thyroid stimulating hormone, which regulates how much T3 and T4 is synthesized and released.

Hyperthyroidism

• When your body makes too much T4, you have hyperthyroidism, which speeds up your body's systems. It can result in unexpected weight loss, a rapid pulse, difficulty sleeping, sweating, and anxiety or irritability.

Hypothyroidism

• When you don't have enough T4, you are hypothyroid. Symptoms can include fatigue, weight gain, depression and constipation.

Top of Range

• In 2001, the American Association of Clinical Endocrinologists (AACE) revised its guidelines and stated that anyone with a TSH level above 3.0 could be considered hypothyroid and treated. The old high end of normal was 5.5; some doctors still use the old range.

Bottom of Range

• A TSH count below 0.3 is considered hyperthyroid. This means that the TSH range that is considered normal by the AACE is 0.3 to 3.0.