Worth noting that this is mostly a US thing. You don’t see so many medicine-like adverts in the UK or EU.
I recall that nuerofen got some adverts banned for falsely implying that different tablets could target different areas of the body when in fact the tablets target all pain. I’m pretty sure you couldn’t make a vague claim that a tablet supports your health if you couldn’t substantiate it.
Governments that dictate what’s “allowed” are authoritarian, it’s not the right frame of mind, government doesn’t “allow”, a government should put reasonable restrictions to obvious society hazards, and always treading carefully when doing so.
As for your specific question, u/cikanman has offered a pretty good answer.
A “medical claim” is very, *very* specifically regulated in the US.
If you:
* Call a product a “supplement” and never use the words “medicine” or “drug”,
* Say it “supports” or “promotes” something but never say it *does* anything,
* Include a disclaimer saying “This product has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease”,
…then you can sell anything you want with any marketing strategy you want.
If your product is ever found to be actively harmful, then there’s a chance it will be investigated, and then there’s a chance that you will be fined. The amount of the fine will probably be much less than you made by selling the product.
If your product isn’t actively harmful, then there’s no law to stop you.
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