Trouble sleeping? It could be an iron deficiency or even anemia. Research has shown that restless leg syndrome, restless sleep or insomnia among infants, children, teenagers and adults is often related to low iron stores.
Restless leg syndrome is characterized by uncomfortable sensations deep in the legs that compel an individual to move. The symptoms are worst at night and sleep disturbance or even insomnia is common. Restless leg syndrome is estimated to afflict 7 to 11% of the adult population which may explain why research initially focused on the elderly. As early as 1994, a study conducted in an Ireland hospital confirmed that iron deficiency, with or without anemia, contributed to restless leg syndrome in elderly patients. Iron supplements were found to significantly reduce their symptoms.1
It is now estimated that 1.9% of children and 2% of adolescents are afflicted with restless leg syndrome.2 Early-onset restless leg syndrome (i.e., before age 30) is genetic, whereas late-onset restless leg syndrome has a strong relationship with an individual’s iron status. A 2002 study determined that abnormal iron stores or metabolism may result in restless leg syndrome causing insomnia in teenagers.3
Iron deficiency, with or without anemia, can impact sleep in other ways. A recent study of 6–18 month-old infants from Nepal and Zanzibar found reduced sleep duration and increased night waking among infants with iron deficiency anemia.4 In a 2007 study conducted on 33 autistic children, researchers found that 77 percent had restless sleep at baseline and that their restless sleep improved significantly with iron therapy.5
The brain transmitter - dopamine - plays a role in neural networks including sleep activity. Iron is vital to the brain’s dopamine system. Hence, iron deficiency is a causative or contributing factor to sleep disorders.
Individuals suffering from a sleep disorder should consult a physician for an evaluation of iron status including serum iron, total iron binding capacity, and ferritin levels. Iron deficiency can be addressed with iron supplements.