If you look at the two top remedies listed on EC for warts, you will quickly notice that Apple Cider Vinegar (ACV) and Banana Peel sit squarely at the top of the list by a very large margin compared to the next closest treatment. ACV is the clear leader over banana peel, also by a wide margin.
Based on those ratings it is interesting to note that both contain considerable amounts of potassium and lesser amounts of zinc. Both zinc and potassium have studies to show that they are both effective for topical application to warts. In fact On the EC list for warts, if you scroll toward the bottom of the list, you will see zinc listed as a remedy.
Another study proven effective wart destroyer is vitamin D, but it is not listed on EC's list of wart removers and I can understand why. Most people start taking vitamin D for healthful benefits, but understand that those benefits are not likely to be visible and few people take vitamin D for the sole purpose of destroying a wart and consequently if you start taking vitamin D for health benefits and weeks later you realize that a long term wart is just gone, you may not draw a connection between the two events. Vitamin D should also be on EC's list of wart destroyers and it should now be clear that vitamin D may be adjunctive to all of the other wart treatments like zinc and potassium.
One of the mentioned drawbacks to the number one recommended wart remedy on EC, ACV, is that it can burn and generally be irritating. Perhaps this can be avoided by taking vitamin D, Zinc and Potassium orally. In this way you are likely to get rid of the wart plus gain benefit internally from these three supplements as well as prevent the return of the wart or warts. Perhaps even add in the a topical zinc ointment directly to the wart to speed the process up. This method is likely to be very useful for people who tend to get warts frequently!
I did not include any study links to keep this a bit shorter, but there are many studies to confirm the above.