06/24/2011 01:46 pm ET | Updated Aug 24, 2011

What Is Graves Disease?

Graves' disease, an immune disorder, has been keeping Missy Elliott out of the hip-hop spotlight over the last three years, the singer recently told People magazine.

The Grammy winner was diagnosed with the disease in 2008, after she started experiencing problems with her motor skills, lumps in her throat, hair loss, mood swings, dizzy spells and bulging eyes, People reported.

Elliott underwent radiation treatment and took medication for the disease, and said her thyroid has been functioning properly for the last nine months, according to People.

Graves' disease affects 2-3 percent of the American population (about 10 million people). So it should come as no surprise that Elliot isn’t the first public figure to battle the chronic condition. Olympic medalist Gail Devers, singer Toni Childs, and former President George Bush and First Lady Barbara Bush all have Graves'. Actress Mary-Louise Parker struggles with a similar form of hypothyroidism.

Graves' disease is the most common form of hyperthyroidism and occurs when a person's immune system attacks the thyroid gland, prompting overproduction of the hormone thyroxine. The higher the level of thyroxine, the faster the body's metabolism is, and an unusually fast metabolism can cause changes in both mood and physical appearance.

The disease is usually not life-threatening, and occurs more often in women than in men (though it can occur in both sexes). Symptoms of Graves' disease include anxiety and irritability, fine tremors in the hands, difficulty sleeping, weight loss, an enlarged thyroid, brittle hair, changes in the menstrual cycle and a rapid heartbeat.

Another common symptom is Graves' ophthalmopathy, which is when the eyeballs bulge out because of swelling in the tissues and muscles behind the eyeballs.

The cause of Graves' disease is still unknown, but risk factors include age (usually develop in people age 20 and older), family history, stress, pregnancy, smoking and being a woman.

There is also no cure for Graves' disease, but there are a number of medications and treatments that can help to control symptoms or decrease the amount of thyroxine the body produces. Some medications include beta blockers (which just relieve symptoms), anti-thyroid medications and radioactive iodine treatments.

Surgery is also an option, by removing the actual thyroid gland.

Elliot's public announcement comes just days before her June 29th appearance on VH1's "Behind the Music," where she will be discussing "almost losing her own life to a health crisis." For now, she seems to be healing properly -- or as she tweeted "I'm doing well feeling great!"