There are sure to be state regulations so as others have said, you'd be best to check those out before you buy a thing.

Once you are sure you comply with all those regulations, then you'd have to be sure you had professional packaging.

I buy several different food items from ebay from time to time and one thing I have noticed is the sellers are not supposed to claim health benefits for these items. Or put it this way, they have to be very careful how they word their ad.

You're saying to us that adding black pepper improves the health benefit but I am not sure if you'd be allowed to say that in the ad. It's something you'd need to check out.