Applying white vinegar daily is not a cure for gray nails. Onychomycosis, commonly known as gray nails. Its a skin disease caused by dermatophytes that invade the nail plate or under the nail. Ringworm of the nail will mainly lead to changes in the appearance of the finger (toe) nails, will not cause pain and itching, but has a certain degree of contagious. Sharing nail clippers, footbaths and other toiletries between ordinary people and people with onychomycosis may lead to infection. Its manifestation is that the fungus starts from the edge of one side of the nail and gradually invades the distal front and side edges of the nail. The manifestations are thickening of the fingernail tip, gray and yellow turbidity, and uneven or broken surface of the fingernail. The treatment of antifungal drugs such as cyclopyrrolone or laser therapy to inhibit the growth of dermatophytes, the application of white vinegar can not treat onychomycosis. If the treatment of gray nails that is ringworm, it is recommended to go to the regular hospital, under the guidance of the doctor reasonable use of medication, do not arbitrarily apply white vinegar.