Your nails reveal your overall health, and while a manicure can hide imperfections, it can’t cover signs of disease. According to the NCBI, nail ridges “may also provide an insight into more sinister systemic manifestations,” signaling possible health issues.

Vertical stripes are common with aging but may also indicate deficiencies in vitamin B12, magnesium, or iron. If they suddenly appear or worsen, conditions like anemia or thyroid issues could be the cause. Horizontal stripes, or Beau’s lines, may result from trauma or serious illnesses like diabetes, heart attacks, or respiratory diseases. The NCBI notes that when found on all nails, they may signal systemic diseases such as pneumonia or syphilis.

White horizontal lines (Muehrcke’s lines) can indicate liver or kidney problems, often linked to low blood protein levels. Most nail changes stem from poor nutrition. Dr. Sara Norris explains, “Brittle, weak, and peeling nails… are more often the result of a poor diet.”