system
Given the following post, respond as if you're commenting on Reddit:
human
Why don't astronauts on the ISS wear lead-lined clothes to block the high radiation load?

They're weightless up there, so the added heft shouldn't be a problem.
gpt
Lead isn't as magical of a radiation shield as it's often portrayed as.  It's really good against x-rays in the diagnostic range, but against anything else it's mediocre and is just used because it's a cheap dense material.

Against high-energy cosmic rays lead can actually be worse than nothing, because the rays can blow apart the big sloppy lead nuclei and the fragments fly off as even more radiation.  A better choice would be something made of light nuclei like water or plastic, and even then you're talking about thicknesses that are just not on the scale of clothing.