Kaye England just gave a talk at our guild. She laughed at people who use these, me being one of those people. I have a red flannel blanket that bleeds everytime I wash it. A couple of husbands white socks are now pink. They work for me. Kaye says to test your fabric before using and wash in cold water. The dye goes out with the water. She asked how many washed underwear before wearing it. Then she said so why wash your fabric first. She says she washes in cold water and has NEVER had a problem. Your choice.