The perspiration stains thing only works a little.

1 to 2 cups added to a load of mildewed clothes or towels in the washing machine will completely remove the mildew smell.

I had to teach this one to my sister in law. Ha

Vinegar is supposed to be very high K+. My Granny Christa's heart medication made her very hypokalemic. Her cardiologist told her to "sip" vinegar & water "tonics" several times a day because she couldn'y stomach the big ole' potassium pills. They don't digest easily. She swore by it and it became a habit she enjoyed over the years. Odd, aye?

Apple Cider Vinegar is also suggested as a mild facial astringent when cut down with water. She swore by that as well...she did have beautiful skin.