Those Pearly Whites.

Losing your adult teeth and never grow them back.

Same body grows a tumor in some random spot in your body and it develops teeth in it. Sakurablossom101

The Autoimmune. 

Autoimmune issues, bar none.

One day your own immune system decides your own organs and whatnot are evil and must be destroyed. The same organs you've had inside you forever that have in no way changed. And the great thing is that usually when you get one, it has a cascade effect and you end up with 2 more within 10-15 years.

First the immune system came for my thyroid. Now if I eat gluten it goes berserk and demolishes my intestines for no real reason. I need those to live. My immune system needs my body ALIVE for IT to live. Why it do this?

I wish someone could come up with a less risky way to do full body radiation. I hear that sometimes zapping away pretty much all of your immune system can reset it in a way. beepborpimajorp

Slumber.

~8 hour down time every 24 hours.

Imagine owning something that works 66% of the time. koifishy420

And even when it does work, it doesn't want to and breaks down easily. And you almost always have to take it to a specialist for repair. The variation in expected usage life is pretty annoying too. ferrettt55

Feeling it All.

That pain is a message that something is wrong, but there isn't a way to actually ask your brain what the issue is. Like dashboard indicators in cars. alienbanter

Pain transmitting nerves are the slowest in the body. The processes that cause acute pain are so much faster than even maximum possible human reflexes (transfer of heat energy from a hot surface to the skin, for example) that there's no chance of you reducing physical damage by moving (up to a point. Don't cuddle space heaters). Acute pain is there to teach you not to do something the NEXT time, IF you survive.

As far as my bioengineering professors were able to tell after studying pain in general and chronic pain in particular for decades, the only clear purpose of chronic pain seems to be to make people crazy. 11thNite

Can't Breathe....

"Hey... pstt... heyyyy!!!!"

"I just detected a small harmless allergen, so I hit the "let's mess stuff up" button. Don't worry bud, I got you." IHaveNowhereElseToGo

A Deep Wound.

Forming a whole body in 9 months but taking 4 months to heal a cut. Enchanted_Lives

If that happened I would agree with you but most normal humans heal a cut in a week or two???? iluvdownvotes-lol

Even my deepest cuts only take a couple weeks. LandOfTheEnd

Where is the Wisdom?

4 teeth that grow just so we can remove them. nardsy43

You've gotta give them credit, they're made out of hydroxyapatite which is the hardest material in nature, heck the Mohrs hardness is higher than a lot of metals. If that isn't... metal... I don't know what is. Ramiel01

Bad Timing. 

You get a new pair of teeth at six years old. Not only do these new teeth grow all weird and not straight but having new teeth as a toddler is completely useless! Imagine having a new set of teeth at age 60 instead. Bonkies1

So Durable. 

The human body is so weird. Simultaneously incredibly durable and horrifyingly fragile. People have survived skydiving accidents where their parachutes never opened, other people have tripped on a flat surface, fallen however far they are tall (or less) and died.

Your legs have some of the strongest bones in your body in them, but hit a joint from the wrong direction and you might end up with an inverted knee, or just a screwed up ACL if your lucky.

It's just weird to think that the same blow, depending on where and how it's applied to the body, can cause the difference between a bruise and death. Ara-Enzeru

My Chest!

Those random, insane chest pains that some people randomly get sometimes when taking a deep breath... which generally indicate that exactly nothing is wrong. What the heck is up with that??

Edit: I'm talking about precordial catch syndrome, as several people have linked. Sorry, probably should have said that originally. CaffeineGlom

Hair. 

Pubic hair. Body be like "testicles need cold, outside they go," and then "why not put a fur coat to warm ya." Not even gonna start about butt hair. BouaphaSWC

Continuous....

Everything in our brains. Our other organs are there working 24/7 to keep us alive and our brains are there like, "what if I put my pinkie on this prong of a phone charger." CrabSmoke

And the fact that our brain is constantly starving for new information but fails to remember half of the information it is given. MomentousMaster

From the Head.

Headaches. ariesbaddie

For that matter, migraines. "Here's a super-headache because screw you!" ferrettt55

"Oh? You're enjoying your day? Time to get head splitting pain with every noise and speck of light! I forgot the best part, you're going to throw up too! :)" KoldGlaze

Lush Lash....

Eyelashes, their main purpose according to biology scientists are that they protect our eyes from debris and harmful germs. In a strange way yeah they do... BUT on the other hand when the debris that gets in your eye is a damn eyelash that is some twisted karma right there. asia_092D

Pipes.

We breathe down the same passage we eat/drink. MakeEveryBonerCount

Sometimes I get the strong urge to drink water to satisfy my dry windpipe and it is the most infuriating thing having to waterboard yourself at 3:28 AM. NootSquared

All the Little Things....

The little things. Acne. Ingrown hairs. Ingrown toenails. The way a smashed finger or toe becomes exponentially more prone to further smashing. asleeplessmalice

27 now, been fighting acne since I was 14. Now I am more annoyed about ingrown hairs and folliculitis than the acne. Why can't my skin just not be angry? I am washing with chlorhexidine and using clindamycin lotion now and that seems to help, and when it doesn't I put mupirocin on it. MRSA sucs. laewin

I Hate you Cancer....

That our cells can just be screwed up in a variety of ways that make them live forever and then all the cells based off those broken cells will likewise live forever... otherwise known as cancer.

Edit: For those who haven't researched or been told the Cliff Notes version of cancer, it goes like this:

The cells that make up our bodies are like all living things: they have a lifecycle. There are various subsystems in our cells that govern that lifecycle.

Cancers occur when a cell has a mutation that causes one or more of those subsystems to malfunction, making said cell stupidly persistent at living too long. And since that cell will beget more cells, they'll all inherit that broken subsystem (or develop their own new, exciting mutations).

Cell reproduction continues and the cells refuse to die. A tumor is born. zeronotzero

Power Point....

It has all there amazing functions but none of them are actually controllable. Cases in point:

• My body can create both muscle and fat tissue. But I can't just tell it to create muscle when I want it to, or to NOT make fat tissue because the likelihood that food will not be available in the near future is basically zero. Or vice-versa.
• If I hit my head, pain is a warning sign that I may have hurt myself. Now I examine the injury, figure out I did not seriously injure myself, but the pain is still there. That's like a fire alarm that can't be turned off, so if there's a false alarm you just need to ignore it for two days.

• I can hear, see, feel, smell, taste. But I can't turn any of that off if, for example, I'm trying to sleep and my roommate snores.
• Getting a boost to your strength and pain tolerance, among other things, through adrenaline is nice if you're in a dangerous situation. Not so nice when that "dangerous situation" is a job interview and adrenaline is making your hands shake.

I'm sure there are more but you get the idea. Aibeit

The Throat Stop. 

Tonsils

Thanks for the horrible strep throat, and tonsillitis you gave me all the time during school. The_Struggle_Man

Tonsils gross me out. Just the idea of them and the tonsil "caverns" or whatever. So yeah I agree. Gruv_3

Shower Away....

• You're more likely to catch a cold from a person by shaking their hand than from their sneezes.
• The human brain weighs about 3 pounds, but uses 20% of one's blood and oxygen.
• Plaque begins reforming 6 hours after brushing your teeth.

Cold showers actually increase sexual arousal.

Man, so weird and stupid. AndromexZ

REDDIT

Anyone else have a few body thoughts they think about?