Yeah it’s kind of impossible to tell. Some of the anti-caking agents can be funky, but I’ve only noticed that in like dollar store salt.
It’s more that the iodine makes pickles cloudy and mushy, and it can fuck up the color of canned goods. There’s also concerns that it could mess with the salt concentration with preserved foods, so you’re making like sausage or canning stuff there’s a slim safety concern.
There’s generally no issue with using iodized salt for general cooking, or especially as table salt. It’s just that coarse salts tend not to come iodized, and course salts are better for cooking.
I try to use iodized table salt once in a while or for table salt, cause I don’t consume a ton of dairy. And that’s apparently the big one in US diets these days. I do eat plenty of fish though.
