When painted, they can add a girly sparkle to hands, and for some people they can substitute as a guitar pick or even a backscratcher. These savvy services, though, are not the reason we humans sport the keratin-rich coverings atop our fingertips. Fingernails are one of the features that distinguish primates , including humans, from other mammals. They are essentially flattened forms of claws. Scientists suspect primates sort of lost their claws and fashioned broad fingertips topped with nails to aid in locomotion.
While claws would have provided excellent grip as our mammalian ancestors clambered up large tree trunks, they would have been a nuisance for larger-bodied primates trying to grasp smaller branches while scrambling across tree canopies for fruits. The legs and feet are also subject to greater concerns related to blood flow, such as deep vein thrombosis or other peripheral vascular diseases. This can affect toenail growth and toenail function. Fingernails comprise three layers of tissue called keratin.
Keratin is a tissue type that has amino acid proteins. Keratin is naturally present in your hair and nails. The way keratin cells link to form together can influence the consistency and feel of the fingernails. For example, the nail layers are made of soft, moderately hard, and hard keratin. These all come together to create the protective shield you know as your fingernails. While the keratin cells are no longer living which is why you can trim your fingernails and toenails , they represent formerly living cells that needed nutrients and proteins to survive.
More about this in the next section. Fingernails may be potential indicators of underlying medical conditions. In fact, doctors frequently assess fingernails to help diagnose different medical conditions. Common nail disorders that may indicate underlying health conditions include the following:.
Ideally, your nails are pink at the nail beds, slightly rounded, with small, shallow vertical lines. If you have variations of this standard appearance that concern you, talk to your doctor. What are your nails made of? Are they really dead? Products and services. Fingernails: Do's and don'ts for healthy nails Are you taking good care of your nails? By Mayo Clinic Staff. Thank you for Subscribing Our Housecall e-newsletter will keep you up-to-date on the latest health information.
Please try again. Something went wrong on our side, please try again. Show references Nails. American Academy of Dermatology. Accessed Dec. Bolognia JL, et al. Nail disorders. In: Dermatology Essentials. Philadelphia, Pa. Habif TP. Nail diseases. Louis, Mo. Rieder EA, et al. Cosmetically induced disorders of the nail with update on contemporary nail manicures. The Journal of Clinical and Aesthetic Dermatology. Brittle splitting nails.
American Osteopathic College of Dermatology.
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