Growth rate of human fingernails and toenails in healthy American young adults
- 5 March 2010
- journal article
- Published by Wiley in Journal of the European Academy of Dermatology and Venereology
- Vol. 24 (4), 420-423
- https://doi.org/10.1111/j.1468-3083.2009.03426.x
Abstract
Human nail clippings are increasingly used in epidemiological studies as biomarkers for assessing diet and environmental exposure to trace elements or other chemical compounds. However, little is known about the growth rate of human nails. To estimate the average growth rate of fingernails and toenails and examine factors that may influence nail growth rate. Twenty-two healthy American young adults marked their nails close to the proximal nail fold with a provided nail file following a standardized protocol, and recorded the date and the distance from the proximal nail fold to the mark. One to three months later, participants recorded the date and distance from the proximal nail fold to the mark again. Nail growth rate was calculated based on recorded distance and time between the two measurements. Average fingernail growth rate was faster than that of toenails (3.47 vs. 1.62 mm/month, P < 0.01). There was no significant difference between right and left fingernail/toenail growth rates. The little fingernail grew slower than other fingernails (P < 0.01); the great toenail grew faster than other toenails (P < 0.01). Younger age, male gender, and onychophagia were associated with faster nail growth rate; however, the differences were not statistically significant. Nail growth rates have increased compared with previous estimates conducted decades ago. Toenail clippings may reflect a long exposure time frame given the relatively slow growth rate.Keywords
This publication has 12 references indexed in Scilit:
- Anatomic considerations of the human nailClinics in Podiatric Medicine and Surgery, 2004
- The Nutrition Transition: An Overview of World Patterns of ChangeNutrition Reviews, 2004
- Modulation of linear nail growth to treat diseases of the nailJournal of the American Academy of Dermatology, 2004
- Secular trends in growthProceedings Of The Nutrition Society, 2000
- A 1-y trial of the effect of high-selenium bread on selenium concentrations in blood and toenailsThe American Journal of Clinical Nutrition, 1993
- FINGERNAIL GROWTH IN NORMAL AND PSORIATIC SUBJECTSBritish Journal of Dermatology, 1970
- OBSERVATIONS ON GROWTH OF FINGERNAILS IN HEALTH AND DISEASEPediatrics, 1959
- A Possible Climatic Effect on Nail GrowthJournal of Applied Physiology, 1958
- Studies of Growth Throughout the Lifespan in Japanese: Growth And Size of Nails and Their Relationship to Age, Sex, Heredity, and Other FactorsJournal of Gerontology, 1955
- STUDIES IN NAIL GROWTHBritish Journal of Dermatology, 1938