Believe it or not, the body is full of parts and organs that you don't actually need to survive. While many of them are there for a specific purpose, and are therefore necessary in some capacity, plenty of people have parts removed due to injury or illness, or to lower their risk of certain diseases — and go on to lead full, healthy lives.
Many times, that's because we have quite a few doubles of things in the body, so it's possible to function when only one is left. "It’s not that having two of the same thing is useless, it’s just that once it’s removed, [the] other half works double time to make up for its lost partner," Caleb Backe, a health and wellness expert at Maple Holistics, tells Bustle. This is often the case when one kidney is removed, or one lung gets damaged, and the other one takes over.
We also have useless body parts and organs leftover from our ancestors, known as vestigial structures. "Our bodies have evolved but some of the vestigial structures have remained," Backe says. "The tailbone and wisdom teeth are examples of these evolutionary changes."
Of course, thanks to the miracles of modern medicine, it's even possible to live without certain body parts we do deem important — though it might mean a slight dip in quality of life. That said, here are the organs and body parts we can live without, according to experts.
1Gallbladder
The gallbladder is a small pouch-like organ located right beneath the liver. It contains bile, which helps digest the fats in food. If that bile gets out of balance, though, hard fragments called gallstones can start to form, according to WebMD. And they're incredibly painful.
If the stones don't go away on their own, a doctor may opt to have the gallbladder removed with a procedure known as a cholecystectomy. In fact, "the gallbladder is a commonly removed organ," Backe says. "In the absence of this organ, your liver pushes the bile directly into the intestines. If you keep up your fiber intake, you can easily live a healthy life without it."
2Appendix
The appendix hangs out in the lower right abdomen, right where the small intestine meets the large intestine, according to WebMD. It's a tube of about four inches long, and apart from one theory that it may "reboot" the digestive system with good bacteria after an illness, seems to have absolutely no purpose whatsoever.
"It contains helpful bacteria to aid digestion, but it is not essential to the digestive process," Backe says. It does, however, have the tendency to get infected and inflamed — causing severe pain known as appendicitis. When that happens, surgeons can perform an appendectomy to get that sucker out of there.
3One Lung
Since we're born with two lungs, it is possible to survive with only one — in the event the other is damaged or needs to be removed. "When one lung is removed, the remaining lung inflates to take up some of the extra space," noted Rachael Rettner, a senior writer at LiveScience. "Living with one lung doesn't usually affect everyday tasks or life expectancy, though a person with one lung wouldn't be able to exercise as strenuously as a healthy person with two lungs."
4Tailbone
At the base of the spine, we all have a few extra bones known as the tailbone, or coccyx. It's a vestigial structure leftover from our ancestors, and it really serves no purpose.
"Other mammals find their tails useful for balance, but when humans learned to walk, the tail [became] useless and evolution converted it to just some fused vertebrae we call a coccyx," LiveScience noted.
It has a few nerves and ligaments attached to it, and should remain within the body. It can also get injured or bruised in a fall, and takes quite a long time to heal. But in terms of functionality, it's definitely not something humans "need."
5Wisdom Teeth
Back in the day, wisdom teeth had their part to play. "Our ancestors used them to thoroughly chew the foliage that their diet mostly consisted of," Backe says. "As our bodies and diet have evolved, these teeth have become more of a nuisance than helpful."
Today, many people leave them in, and don't have any problems. But for others, wisdom teeth can cause crowding within the mouth, they often get impacted and inflamed, and they can become painful — which is why dentists often recommend they be pulled.
6Spleen
Unlike the gallbladder or the appendix, the spleen is actually a helpful little part of the human anatomy. Located in the upper left part of the abdomen, the spleen "acts as a filter for blood as part of the immune system," Matthew Hoffman, MD noted on WebMD. "Old red blood cells are recycled in the spleen, and platelets and white blood cells are stored there. The spleen also helps fight certain kinds of bacteria that cause pneumonia and meningitis."
That said, "the spleen is a body organ we can survive without," Dr. Kelenne Tuitt, a board-certified family physician, tells Bustle. "It is usually removed if damaged. The function of the spleen is to help filter the blood of toxins and to help fight off infections. It is not necessary to have this organ as we have multiple defense mechanisms to prevent infection."
7Uterus
People with uteruses may need to have them removed for medical reasons, and can go on to live perfectly healthy lives. "[Someone] can have their uterus removed in a hysterectomy as a treatment for cancer, uterine fibroids, chronic pelvic pain, or other reasons," Rettner said. "About [one in three] women in the United States [have] had the procedure by age 60, according to the National Institutes of Health." Someone can also have their ovaries removed, as well as other parts of the reproductive system, and live a normal life.
8One Kidney
There are many reasons why someone might have one kidney, instead of the usual two. According to the National Kidney Foundation, it's possible to be born with only one. Sometimes, people have a kidney surgically removed in order to donate it. And other times, it's necessary to remove one due to disease or injury.
While living with one kidney can lead to a slight loss of kidney function later in life, most people live without it quite normally. As long as their other kidney is healthy and functioning properly, they can survive with just one.
9Colon
As a way of treating or preventing certain diseases — such as colon cancer or Crohn's disease — many people end up having their colon fully removed. And that's OK.
"People can live without a colon, but may need to wear a bag outside their body to collect stool," Rettner said. "However, a surgical procedure can be performed to create a pouch in the small intestine that takes the place of the colon, and in this case, wearing a bag is not necessary, according to the Mayo Clinic."
10Bladder
Similarly, the bladder can also be removed via an operation called a cystectomy, which is used as a way to treat bladder cancer, or tumors on other organs in the pelvic area, according to the Mayo Clinic.
A person can go on to live a healthy life, but will have to find another way to pass their urine. A doctor may insert a tube that drains pee from the kidneys to a bag outside the body. It's also possible to create a reservoir inside the body, according to WebMD, in order to pee more naturally.
It's possible to live a healthy life without these body parts, either because they're vestigial structures, due to the fact humans have two of them — or thanks to modern medical procedures. It just goes to show how amazing the body is, when it comes to adapting and maintaining good health.
