TL;DR
People have long sworn by cold plunges and icy swims, and the idea behind them has a name: cold hormesis, the notion that a little cold stress makes the body stronger. A new study traced that idea down to a single small molecule. In tiny roundworms, cold pushed muscle to make more of a molecule called BH2, which traveled to other tissues and was linked to longer life and less buildup of clumped, damaged protein. In human cells grown in the lab, adding BH2, or the related amino acid tyrosine, cut the clumping of proteins tied to Huntington's disease and ALS. This is worms and lab cells only, described in a secondary report. What makes it exciting is the shape of the lead: a small molecule that mimics cold could, in principle, be tested as a pill or supplement far sooner than any gene-based approach, which raises the hope that some of the benefits of the cold could one day come without the shivering. For our odds on when a cold-mimicking pill reaches people, and the timeline of breakthroughs that leads there, subscribe.
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