Restless legs syndrome is a serious neurological disorder. It involves an irresistible urge to move certain regions of the human body to stop odd or uncomfortable sensation. This condition often involves the legs, torso, the head or the arms. Moving an affected part of the body modulates sensations, which may provide temporary relief. Around 75% of people who have RLS have problems involving iron. Other possible issues include varicose veins, sleep troubles, conditions involving blood sugar, ADHD or fibromyalgia.