Nail Changes That Can Signal Health Problems

1. Horizontal lines (Beau’s lines)
“These can suggest past illness, significant stress, or chronic conditions such as diabetes or circulation issues.” In reality, they appear after any strong shock to the body (high fever, surgery, chemotherapy, or severe physical stress) and usually affect all nails at once. They grow out on their own.

2. Vertical ridges
Normal with aging in most people. “While common with aging, unusually deep or uneven ridges could point to nutritional deficiencies like iron or vitamin B12 shortage.” Only very pronounced or sudden changes are worth checking.

3. Dark streaks
“Sudden appearance of dark streaks may signal melanoma, a serious skin cancer, and require immediate medical attention.” True if the streak appears out of nowhere, widens quickly, or affects only one nail. Long-standing dark lines (especially in darker skin tones) are almost always harmless pigment.

4. White horizontal lines (Muehrcke’s lines)
“These may be linked to liver or kidney problems, or low protein levels.” They are rare and usually come in pairs. They disappear when blood protein (albumin) returns to normal.

5. Bottom line
“After age 40, changes in your nails—especially unusual lines—should not be ignored.” Most changes are harmless, but any new, rapid, or single-nail change deserves a quick check with a doctor. Your nails whisper, they rarely scream.