Almost a hundred years ago some salt companies started voluntarily adding potassium iodide to their product to help reduce the instance of goiter in the American population, and in the intervening years we’ve gotten so used to seeing the “This salt supplies iodide, a necessary nutrient” distinction that we don’t think much about it. That is, until we see the opposite labeling: “This salt does not supply iodide, a necessary nutrient.” Then we wonder what that means and which choice is the right one. If iodide is necessary, shouldn’t we get the salt with it? If we don’t, are we going to be missing out on something? What’s the difference between them anyway?
As you noticed, Real Salt falls into the category of not supplying iodide. This is because the FDA mandates that unless you add potassium iodide to salt, you have to state on the packaging that it doesn’t supply iodide. If you’ve been using Real Salt for a while, you know that one of the things that makes it special is the fact that it is unrefined. Unrefined means we don’t take anything out of it—like magnesium, potassium, or calcium—and we don’t add anything to it—like anti-caking agents, dextrose, or potassium iodide. We believe nature knew what she was doing when she created salt, so we choose to leave it be.
Iodized salt is generally going to be the highly processed, uniform-looking conventional table salt. During the process wherein the salt is refined and stripped of its minerals (and unique flavor), potassium iodide is added. So, you get the partial benefit of added iodine but you don’t get the minerals nature intended.
Real Salt does contain some naturally-occurring iodine, but it’s not enough to meet your daily needs. The iodine in salt—even the intentionally added sort—isn’t very bioavailable anyway, which means your body isn’t going to absorb much of it. In fact, studies show you will absorb as little as 10% of it. It’s better to eat foods that provide iodine naturally, like shellfish, sea vegetables, cranberries, yogurt, and cheese, and use salt to their enhance flavor.