Saline injected into forehead for 'bagel' effect - video
The bagel-shaped foreheads - currently being showcased on National Geographic television show Taboo - will shrink back to normal with no long-term effects.
Photographer Ryoichi Maeda previously explained to Vice: "We use medical saline solution and using infusion we pump it into the forehead for about two hours, or until it's ready.
"Everyone I know who has done it, no matter how many times, their skin has gone back to exactly how it was before.
"You just press your thumb into the middle of the forehead while the saline is being pumped in, and that creates the doughnut, bagel effect."
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