eHow Extras Blog

How Old Is Your Body?: 8 Parts of Your Body and Their Actual Age


Your birth certificate may say you’re a certain age, but individual parts of your body are a lot younger than you think—in some cases only a couple weeks old. Why? A healthy body regenerates like the T-1000 in Terminator. What does it all mean? Among other things, it means every mouthful of food you put in your body affects how healthy your body’s regeneration cycles are.


Your Skin: 27 Days
As the body’s largest organ (about 16 percent of your body weight), your skin’s dead cells are constantly flaking off. Where does all that skin go? If they’re not washed off while you bathe, they literally become dust in the wind. The body loses 30,000 to 40,000 skin cells an hour so that’s a lot of dust. And the most asked question: Why don’t tattoos flake off if my skin is constantly regenerating? Because tattoo ink is injected into the second, more stable, dermal layer of the skin. Tattoos fade—just at a super slow pace. Bad news for Mike Tyson. Source

Your Taste Buds: 10 Days
Look at your tongue in the mirror—you’re looking at around 2,000 to 10,000 taste buds and those buds? They each have about 50 taste cells. Nicholas Bower, MD, district medical director at MedExpress, says anyone in the 10,000 range is considered a “supertaster” and literally has better taste than others. Also of note, smokers will often suffer from damage during their buds’ renewal, deadening sensitivity. Source

Your Heart: 75 Years (Over an Average Lifespan)
Not too long ago in the ‘70s, it was thought that the heart couldn’t renew itself, but research in the late ‘80s at New York Medical College by Dr. Piero Anversa has found the heart as a whole is generating new cells. Additional new research by Dr. Jonas Frisen of the Karolinska Institute in Stockholm is backing Anversa’s once unbelievable theory. Source

Your Liver: 5 Months
Your liver is a crazy organ—thanks to a rich, healthy blood flow, it can repair and regenerate like new. “I can take 70 percent of a person’s liver away in an operation and around 90 percent of it will grow back within two months,” explains David Lloyd, consultant liver surgeon at Leicester Royal Infirmary. Sure the liver can take a couple shots of tequila, but heavy drinkers who don’t give their liver a chance to rest will damage parenchymal cells (the liver’s main cells) which then form permanent scar tissue, a.k.a. cirrhosis. Once that happens, regrowth stops. Source

Your Lungs: 2 to 3 Weeks

The lungs are tricky and pretty awesome. They have different cells that regenerate at different rates of speed. The part of the lung I’m talking about here is the outer surface—the first line of defense. It’s constantly protecting you so it has to renew fast. Great news if you’re a moderate smoker thinking of quitting. Unfortunately, hardcore smoking destroys cilia, the tiny hairs in your lungs that protect your lungs against infection. Once that happens, like your liver, permanent scarring occurs and cilia regrowth stops. Source

Your Nails: 4 to 6 Months for Fingers, 10 to 12 Months for Toes
An average adult’s fingernail grows about one-tenth of an inch a month—convert that into a full nail and you’re looking at new nails every four to six months (although the pinkie takes a bit longer). Toenails are a completely different story—about a full year from cuticle to the tip. Source

Your Bones: 10 Years
Solid bone seems a lot different than the heart, liver or lungs, right? You wouldn’t think they regenerate themselves, but they do. Osteoclast cells are constantly breaking down your existing bone so that they can be replaced with new bone tissue–a process called bone remodeling. And get this, in the first year of life, almost 100 percent of the skeleton is replaced—as adults, remodeling happens at about 10 percent every year. Source

Your Hair: 2 to 6 Years
The age of your hair is obviously going to be determined by its length, but if you’re relatively healthy, it grows at a rate of half-an-inch per month or six inches a year. Each individual strand of hair lasts up to six years for women and three years for men. (That said, Jennifer Aniston’s hair as superhuman properties—biological laws don’t apply to her.) Weird fact: Hair has three stages (Anagen where hair grows for 2 to 7 years; Catagen, the transition stage; and Telogen, its resting phase). When your hair reaches the Catagen phase, extreme stress can lead up to 70 percent of your hair to zoom into the Telogen stage where hair loss occurs. So yeah, stress does cause hair loss. Source

All images: GettyImages (except the top image,

Read Previous: 9 Websites to Get a Free Education in Higher Learning

Read Next: 7 Legitimate Ways to Earn Extra Money at Your Pace (and Sometimes in Your Pajamas)

Promoted By Zergnet


Is DIY in your DNA? Become part of our maker community.
Submit Your Work!