What do Beau's lines indicate?

Beau's lines are characterized by indentations or grooves that run horizontally across the nails, and they indicate that there's been a temporary disruption in the growth of the nail matrix. This disruption is typically caused by various factors, such as severe illness, malnutrition, or trauma, which lead to a slowdown in nail growth. The presence of these lines serves as a visual record of past health challenges or stressors that the body has experienced, reflecting the time when nail growth was affected.

In contrast, normal nail growth does not produce any visible lines, and a growing nail infection would often result in discoloration, swelling, or other symptoms rather than lines. Similarly, while cosmetic nail issues might alter the appearance of the nails, they wouldn't typically manifest as horizontal grooves indicative of growth disturbances like Beau's lines do. Thus, identifying Beau's lines provides important insights into the health and conditions that the individual has previously faced.