Bono Bono

U2's Bono, the lead singer from that band that showed up on your iTunes unannounced, is rarely seen without his trademark sunglasses. But now we know why Bono is always sporting shades, and it isn't because his future is so bright.

Speaking on BBC1's The Graham Norton Show, Bono revealed that the real reason he wears sunglasses all the time is that he has been suffering from glaucoma for the past 20 years.

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Glaucoma is a condition in which pressure builds up inside the eye and can cause stress on the optic nerve. As a result, those who suffer from glaucoma are more sensitive to light.

But don't worry for the superstar. "I have good treatments and I am going to be fine," Bono said. And his sunglasses are really expensive, too.

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