Fainting, also called syncope, is a sudden and brief loss of consciousness followed by a spontaneous return to wakefulness—people who faint “black out” and then “come to” on their own without outside intervention.
“The elderly have syncope more commonly than any other group,” which can put them at risk of falls and fractures. Often the spells are caused by actions as simple as changing position or eating a meal. When we stand up, “about half a liter of blood immediately goes to the legs and the lower abdomen,” and eating also pulls blood from the brain to the gut. Our bodies compensate by raising the heart rate to get blood to the brain. But elderly people can’t always restore their blood flow, and dehydration or certain medications can exacerbate the problem.