Thrown Up Science

For many, throwing up or vomiting is the most dreaded form of an illness. As unpleasant as it is, your body is trying to do you a favor by making you throw up. It’s still a pretty horrible process but maybe understanding why and how it all happens will help just a little.

This isn’t going to be about what throw up is. That might just be a little too gross and it is pretty easy to figure out what is in throw up. And if you can’t figure it out then a simple google search will take care of those curiosities for you.

Why we throw up

The most common reason for throwing up is to get rid of something your body feels is harmful to you. This could be a nasty virus or a chemical that the body is worried about. Instead of allowing those items to pass through your entire body, your body works to remove them much quicker.

You can also throw up if you get very dizzy. Scientists have some differing thoughts on why motion can make you throw up. What is clear is that motion sickness occurs when your brain senses motion or non-motion and your eyes sense differently. In other words, this tends to happen when your body is relatively motionless but your surroundings are moving. That sends mixed signals to the brain. But why does that make you get sick to your stomach? The leading hypothesis is that the mixed signals are telling your brain that something is wrong and that may have been caused by a poison of some sort — so it instructs your stomach to start the vomiting sequence.

How we throw up

Your stomach is lined with special sensor cells that use a chemical called serotonin to communicate with the nervous system. When the stomach sensors detect something bad, they send a signal to the nervous system, which then sends a signal to your brain.

The command to throw up actually comes from your brain, not your stomach. When the brain receives enough signals, it will send a return signal to your stomach to start the process of vomiting.

After receiving the vomiting signal, your stomach muscles contract all at once, which squeezes everything while increasing the pressure. Then all at once the “cover” on your stomach relaxes and the contents of your stomach erupt out.

As horrible as it is, your body does help make things just a little better. First, most of the time your brain will give you that sick feeling to warn you that something is going to happen. Second, just before throwing up your body produces extra saliva, which helps protect your teeth from the strong acid. Third, the vomiting process releases chemicals in your body to make you feel better. So that “I feel better” feeling after throwing up is not just your imagination — it’s your biology working.

Contagious throw up? 

Are you one of those people that almost throws up when somebody near you throws up? What’s the deal with that? Scientists believe it was evolution that produced that behavior in order to save you. Save you from what?

It is believed that the contagious throwing up developed in primates. Primates stayed in groups to forage for food. So, if one primate started throwing up, it might be helpful if that caused the others to throw up since they were likely eating the same food. That trait was passed down and down and still remains in some of us today. The trait is just sitting there waiting for somebody near you to throw up because just maybe you also ate the spoiled or poisoned food.