Tea tree oil kills MRSA on the skin. All the low dose natural products are causing the bacteria to become resistant. Otherwise, for fungal infections soaking feet in vinegar once a day for a week should work just fine. Smells a little.

I wasn't using low dose natural products on my feet.

I had a spray can of 100% tea tree oil that I would spray on my feet. It would sting like hell anywhere I had broken skin but it was effective.

Iodine is much more pleasant to use and doesn't smell so bad, it's cheaper too.

Doesn’t it stain?

Temporarily, it then sublimes directly into gas form without passing through a liquid phase. (Verify before you use it everywhere, but this is what I would expect with the mixes I've used. Also see https://en.wikipedia.org/wiki/Iodine)

The best thing I've found for fungal infections on feet (more effective and faster acting than commercial products) is simple vinegar and garlic. Crush up a few cloves, (maybe microwave in small amount of water for a few seconds), pour a cup or three of vinegar in a container with maybe 3-4 times that amount of water, put the crushed cloves in, let it seep for a bit and soak feet for awhile.

I'm sure there is a more exact specification, but it all seems to work. Problem gone in a day or so.

I can beat that.

Get some bleach, mix in a basin with some water. No good exact amounts, it should smell bleachy and be diluted a fair bit past the point of burning.

Do this, then a couple days later, do it again. Whatever has taken residence on your feet will have moved out.

In China it isn't uncommon for newborn babies to be bathed with tea tree oil (and other plant/herb products) for the first few weeks. I'm not sure what the strength is though.

Could you elaborate on the iodine?

I use povidone-iodine, the common brand name for it is Betadine. It either comes in a small dropper bottle, or as ointment.

You just apply it topically and it will kill any fungal infection within a couple of days.