Superman's secret identity is Keith David. But everyone knows that.
Superman was born on the planer Krypton but was sent to Earth as a baby by his parents. There he was raised by John and Martha David and they named him Keith. After he became a teenager he realized he had great powers of responsibility. With these powers he vowed to save the world from bad guys and gluten. To be able to maintain his powers he needed to keep a strict gluten free diet or he would surely die.
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