Missy Elliot and 7 things you need to know about Graves’ disease.

Hip-hop star Missy Elliot says the reason she hasn’t been seen much lately is that she has been suffering from Graves’ Disease. Elliot, 39, told People magazine that she was diagnosed with the thyroid condition in 2008. At that time, the disease “began affecting her motor skills, followed by a string of symptoms: dizzy spells, lumps in her throat, mood swings, hair loss, a fast heart rate and bulging eyes.” Her doctors treated her with radiation therapy and medication, and she is reportedly feeling “much better.” Elliot will be the subject of a new VH1’s Behind the Music episode which will air tonight.

Seven things you need to know about Graves’ Disease

1. Graves’ disease, also known as toxic diffuse goiter, is the most common cause of hyperthyroidism in the United States. Hyperthyroidism means that the thyroid gland is making more thyroid hormone than the body needs.

2. The thyroid is a small, butterfly-shaped gland in the front of the neck below the larynx, or voice box. The thyroid gland makes two thyroid hormones, triiodothyronine (T3) and thyroxine (T4). Thyroid hormones affect metabolism, brain development, breathing, heart and nervous system functions, body temperature, muscle strength, skin dryness, menstrual cycles, weight, and cholesterol levels.

3. Graves’ disease is an autoimmune disorder, meaning the body’s immune system acts against its own healthy cells and tissues. In Graves’ Disease, the antibodies the body makes act to stimulate the thyroid to make more thyroid hormone.

4. Graves disease is much more common in women than men- 5 to 10 times more common!

5. The symptoms of Graves’ disease include:

• nervousness or irritability
• fatigue or muscle weakness
• heat intolerance
• trouble sleeping
• hand tremors
• rapid and irregular heartbeat
• frequent bowel movements or diarrhea
• weight loss
• goiter, which is an enlarged thyroid that may cause the neck to look swollen

6. People with Graves’ disease may also have bulging eyes, a condition called Graves’ ophthalmopathy.

7. Graves’ disease is most often treated with radioiodine therapy, which gradually destroys the cells of the thyroid gland. Antithyroid drugs and surgery to remove the thyroid are sometimes used.

For more information about Graves’ Disease and Graves’ Ophthalmopathy, check out our story about Barbara Bush.