For natural nails, a nail file with a higher grit number, such as 220 or 320, should be used to prevent damage. These higher grit files are finer and gentler on the nail, reducing the risk of splitting or peeling.
When working with natural nails, it is essential to use the correct grit file to prevent damage. The coarseness of a nail file is measured by its grit number, and for natural nails, a higher grit number indicates a finer file that is less likely to cause damage. An 80 grit file is too coarse for natural nails and is usually reserved for artificial nails or for removing a significant amount of nail material quickly.
A 120 grit file can still be too harsh for natural nails, and could lead to splitting or peeling. On the other hand, a 220 grit or 320 grit file is much finer and more suitable for the natural nail, as they can shape the nail without causing unnecessary stress to the nail plate. Thus, either 220 or 320 grit nail files are recommended for safely filing natural nails.