Anyone who suffers from Alzheimer’s—or watches as a loved one does—knows how crippling the disease can be. In inspiring news, scientists can now detect early warning signs years before symptoms appear. Here’s how: radioactive dye is injected into a person’s arm, attaching to proteins called amyloid plaque, which appear on PET brain scans if there is Alzheimer’s risk.

It’s not a cure yet, but detection is certainly a step in the right direction!

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