TL;DR
Skin looks young when it can snap back, and the fiber that lets it do that is elastin. The body all but stops making elastin in adulthood, so once sun and years wear it down, slack, sagging skin follows and no cream rebuilds it. A team in China has now used the same mRNA-in-a-fat-bubble trick behind the COVID vaccines to hand skin cells the instructions to build elastin again, and in animal models the skin laid down fresh elastic fiber and pushed back both sun damage and ordinary aging. The promise is skin that firms from the inside without a scalpel: a shot that tells a drooping earlobe, a slack jawline or a crepey cheek to make the springy protein it gave up decades ago. The result is in animal-model skin for now; our odds that an elastin treatment restores youthful snap to people's skin put the chance it works at 60%, likely by 2037. To read the full odds and the timeline of breakthroughs that leads there, subscribe.
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