Missy Elliot recently told People magazine she suffers from an illness called Graves' disease. Graves' disease is an ailment that affects the autoimmune system and thyroid gland.

According to a report by the Washington Post, Graves' disease occurs when too much thyroid hormone is produced leading to hyperthyroidism. When thyroxine levels are increased so is the metabolic rate which could lead to imbalances in weight, mood and energy.

Symptoms to Graves' disease include rapid heart rate, double vision, insomnia, tremors, fatigue, muscle weakness and anxiety.

Rapper and producer Missy Elliot said she suffered hair loss, mood swings and muscle control loss when she was first diagnosed with the condition three years ago.

The 39 year old rapper  said she was treated with radiation therapy and exercise. Other treatments include anti-thyroid medications and doses of radioactive iodine to shrink the gland.

If left untreated Graves' disease can get worse with time. Missy Elliot was diagnosed early and can continue to live a normal life. President H.W. Bush and Frist Lady Barbara Bush also suffered from Graves' disease.

According to the report by the Washington Post, Elliot is now producing more songs with Timbaland for her highly-anticipated seventh album titled Block Party.