I see people all the time with dirt under their nails and men/women with long nails. I see several people on a daily basis biting their nails which is a gross habit. I see those who bite their nails even with dirt under them too. Every time I see this I want to gag. What is living under those nails that you just put in your mouth?
First off keratin is a protein that makes our nails flat and hard. This substance also creates our hair and "the top layer of our skin". Even in the womb we have finger nails/toenails. Our nails actually begin in what's known as the nail root. This is located under our skin behind the cuticle. The cuticle is where the nail touches the skin and the lunula is the "pale half circle just above the cuticle". Our nails continue to grow because new nail cells grow under our skin and force the old nail out. Under our nail is called the nail bed; it's made up of blood vessels that keep our nail healthy and that give it a pink tint. Our fingernails grow 2.5 millimeters per month and this is why it will take three to six months to replace a whole nail once you lose it. To keep our nails healthy it's recommended that we cut our fingernails and toenails straight across and to regularly put lotion on our nails and cuticles to add moisture. ("Your").
Dr. Anthony Hilton, a microbiologist from Aston University, held a study of nail clippings from fifty-five women and forty-five men. He had found enterobacteriaceae under 24% of men and 15% from women. Enterobacteriaceae causes vomiting, diarrhea, and gastroenteritis and is usually found "in the guts of animals or humans" ("Quarter"). Another study done by Dr. David Katz from Yale University swabbed several students with different fingernails lengths. He let the bacteria grow for three days in which he concluded the short, painted nails had the least bacteria under them. Unlike those with long unpainted nails, who had the most bacteria. Nails that are shorter are able to be cleaned easier and nail polish has a few chemicals that includes the chemical formaldehyde, which actually decreases bacteria growth ("Biting"). In another study it was found that "infectious outbreaks in neonatal intensive care units were linked to long nails". Eighteen health-care workers were tested and the study concluded that longer nails contained bacteria compared to 18% of the health-care workers who had shorter nails. Klebsiella, a bacteria that causes pneumonia, urinary tract infections, and a yeast that can cause blood stream infections were found under several of these nails. This is very scary especially when the workers help those who are already ill and vulnerable ("Study").
Onychophagia also known as nail biting occurs in about 45% of teenagers. Nail biting could be caused by stress, anxiety, OCD, or just a habit. When biting your nails you put all the bacteria under the nails into your mouth and gums, let alone possibly creating infection in your fingers by breaking the skin when biting. Nail biting can also damage your teeth by weakening and wearing down the enamel on the teeth ("Mouth").
Many of these studies need more people to be involved in the tests to have stronger results. Also many third variables can play a role like the jobs of students and the environment they live in at home that can affect the bacteria under their nails. As you have read biting nails are not healthy so here are some tips on how to stop.
"Biting Your Nails Part 2." Huffpost Healthy Living. 30 Nov. 2013 <http://www.huffingtonpost.com/thomas-p-connelly-dds/stop-biting-nails-_b_604665.html>.
"Mouth Health: The Dish on Biting Your Nails." Huffpost Healthy Living. 30 Nov. 2013 <http://www.huffingtonpost.com/thomas-p-connelly-dds/mouth-health-the-dish-on_b_574866.html>.
"Quarter of Men Have Germs Lurking Under Fingernails." Mail Online. 30 Nov. 2013 <http://www.dailymail.co.uk/health/article-472410/Quarter-men-germs-lurking-fingernails.html>.
"Study Links Long Fingernails and Bacteria." ABC News. 30 Nov 2013 <http://abcnews.go.com/Health/story?id=117161>.
"Your Nails." KidsHealth. 30 Nov. 2013 <http://kidshealth.org/kid/htbw/your_nails.html>.
Photo of dirty nails:
Photo of woman biting nails: