 Reported for the first time recently, case reports of aspartame-induced fibromyalgia, an unusual but curable cause of chronic pain. A 50-year-old woman had been suffering from widespread pain and fatigue for more than 10 years, leading to the diagnosis of fibromyalgia. But during a vacation in foreign countries, she did not suffer from painful symptoms and made a connection with the fact that she had forgotten to take her aspartame. All the symptoms reappeared in the days following her return when she reintroduced aspartame into her daily diet, but when it was definitively excluded from her diet, resulted in a complete regression of her fibromyalgia symptoms after 10 years of suffering. A 43-year-old man consulted for a three-year history of bilateral forearm, wrist and hand and neck pain, various unsuccessful treatments. A detailed questioning followed to find out that he had been taking aspartame for three years. The removal of aspartame was followed by a complete regression of pain without recurrence. The benefit-risk ratio of considering the diagnosis of aspartame-induced chronic pain is obvious. The potential benefit is to cure a disabling chronic illness, to spare numerous laboratory and imaging investigations and to avoid potentially harmful therapies. The potential risk is what, to temporarily change the patient's diet? Thus, practitioners should ask patients suffering from fibromyalgia about their intake of aspartame. In some cases, this simple question might lead to the resolution of a disabling chronic disease. And fibromyalgia is no small pain in the neck, affecting an estimated 5 million Americans who should all be asked that simple question.