A 2010 study found fingernails grew about 3.47 millimeters a month on average, more than twice as fast as toenails, which grew 1.62 millimeters.
ILLUSTRATION · AIA 2010 study of 22 healthy American young adults found fingernails grew an average of 3.47 millimeters a month, more than twice as fast as toenails.
S. Yaemsiri and colleagues asked 22 healthy American young adults to mark their nails near the base with a nail file and record the distance to the mark. One to three months later, the participants measured again, and the researchers calculated growth from the distance and time between the two measurements. The results appeared in the Journal of the European Academy of Dermatology and Venereology in 2010.
Average fingernail growth in the group was 3.47 millimeters per month, against 1.62 millimeters per month for toenails. The researchers concluded that nail growth rates have increased compared with estimates made decades earlier.
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