While that might be what’s driving it there are ways around it. Zinc isn’t directly patentable but you could patent a specific way to package it.
I could imagine packing it in Lozenges with copper might be a good idea. Taking a lot of Zinc reduces your copper absorption, so that you need to consume more copper when taking a lot of Zinc. It’s also possible that the copper helps directly.
While that might be what’s driving it there are ways around it. Zinc isn’t directly patentable but you could patent a specific way to package it.
I could imagine packing it in Lozenges with copper might be a good idea. Taking a lot of Zinc reduces your copper absorption, so that you need to consume more copper when taking a lot of Zinc. It’s also possible that the copper helps directly.