Whether it’s before a big interview or you’re sitting next to your crush wondering what to say, people will be all too familiar with the fluttery, almost ticklish feeling that brews in their midriff when they’re excited or nervous. But why does it happen?

Most of us know this feeling by the un-scientific name “butterflies,” as it might feel like a few are fluttering around in your stomach. However, there’s a more scientific explanation for it.

Anyone who watched B Rabbit (aka Eminem) introduce his mom’s spaghetti to a toilet bowl (and the front of his sweater) before his epic battle in 8 Mile will not be surprised to learn that the digestive system has close links to thoughts and emotions.

That’s why those pre-presentation jitters can quickly turn into stomach acrobatics. In this article, we explain how the body turns excitement into a gut punch or belly rub.

Brain health and gut health are close cousins — and not just because you might have last night’s burger still pushing against the sides of your digestive tract while you’re thinking about the next serving. Some researchers refer to the GI tract as the “second brain.”

Research suggests that the gut and brain regularly slide into each others’ DMs, likely exchanging nothing but poop emojis. Scientists call this group chat “the brain-gut axis.”

Chronic stress can actually change which bacteria live in your gut. This little civilization of microbes is called the microbiota.Househam AM, et al. (2017). The effects of stress and meditation on the immune system, human microbiota, and epigenetics. https://www.ncbi.nlm.nih.gov/pubmed/29306937

Research has also linked changes in the gut microbiota to both gastrointestinal (GI) disorders and mental health problems, including depression and anxiety.Zhou L, et al. (2015). Psychobiotics and the gut-brain axis: In the pursuit of happiness. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4370913/pdf/ndt-11-715.pdf

When you feel nervous before a stage debut or big meeting, your brain communicates that anxiety to your gut. This lets loose a swarm of butterflies.

To fully understand why butterflies feel how they do, we may have to look back hundreds of thousands of years. (That’s a long time, to be honest. Our stomachs are doing somersaults just thinking about it.)

Butterflies in the stomach are BFFs with the body’s fight-or-flight response, which has origins in how humans evolved.

Before humans had to be ready for the finale of their favorite show or following their Uber to the final meter of its journey on the app, they had to prepare to run from attacking lions (or other prehistoric beasts).

Given the typically narrow window between a lion deciding to order a human fillet and you ending up on the plate, an increased heart rate and tense muscles could be the secret weapon you needed to make a quick escape.

When your brain perceives a potential threat to survival, it increases alertness by raising your heart rate, blood pressure, and breathing rate.

At the same time, the nervous system wakes up your adrenal glands, which release hormones like adrenaline and cortisol that prepare your body to get the hell away from that lion (or what have you).

Blood leaves places where it’s not needed, like the stomach — it’s not like you’re about to eat the lion. They are not especially easy to negotiate with.

Instead, blood flows to body parts where it might be necessary, like the muscles. That’s why cavemen’s legs could spring into action when they needed to run for their lives, and also why you should never skip leg day at the gym. Every day is leg day when bears want your face on a stick.

The smooth stomach muscles are extra sensitive during the fight-or-flight response, which may explain the sensation of a million flying insects in your belly.

Digestion also slows down. So, feeling like you want to throw up before a big interview is perfectly natural.Mertz H. (n.d.). Stress and the gut. https://www.med.unc.edu/ibs/files/2017/10/Stress-and-the-Gut.pdf

A job interview isn’t necessarily a life-threatening situation. Yet our bodies still deal with stress in much the same way as they handled scenes stolen squarely from “The Lion King” in ages past.

And anyone at the fourth stage of a five-stage job interview can testify that you might as well be facing down a herd of wildebeest, as far as your body is concerned.

The kidneys do not automatically sit down and write out a boss-ass resume. Your body reacts to stress in the same way your ancestors’ did. Only the things that can stress us out or hurt us have largely changed.

Butterflies are usually harmless and can sometimes feel pretty great. If you’re about to get close to a partner for the first time, your belly may well be full of them. It’s a sign of attraction surer than even takeout in bed together.

However, if these fight-or-flight feelings interfere with your daily life or happen with seemingly little warning or stimulus, it might be time to see a doctor.

If your stomach regularly feels the way it does before a job interview, it could be a sign of an anxiety disorder or even a gastrointestinal issue.

Anxiety is a natural and healthy response to the worrying things that life can throw at you, tied to our time spent as hunter-gatherers, which might be something to bring up in your next butterfly-inducing job interview. (Mad skills at collecting berries could work in your favor.)

An anxiety disorder can develop when the mechanism that triggers these feelings is rusty or oversensitive.

You know when your phone screen is frozen and it types out whichever letter you push 10,000 times? Anxiety disorder does a similar thing to your internal fight-or-flight widgets.

One way to deal with butterflies is to breathe deeply and relax. Meditation can also help manage the stress that makes your stomach churn, if you get into a daily routine of it. Techniques like tapping (aka EFT) can also help.

To try a simple meditation: Close your eyes, breathe from your diaphragm, and repeat a word or mantra over and over until your belly calms down. “This, too, shall pass” is an excellent choice, but it can help to pick a mantra that particularly reassures you or means something special.

Other ways to calm your shrieking stomach could include:

  • Give pats to a nearby pupper: Recent research showed that doing so significantly reduced anxiety in people attending an emergency room for treatment.Kline JA, et al. (2019). Controlled clinical trial of canine therapy versus usual care to reduce patient anxiety in the emergency department. DOI 10.1371/journal.pone.0209232
  • Move around: doing jumping jacks, push-ups, or another quick exercise can release some tension.
  • Try CBD: A few drops of cannabidiol (CBD) oil may help calm the body without making your head disappear down a weed wormhole.
  • Squeeze a stress ball: This works great when paired with deep breathing.
  • Do an inversion: Lay on your back in front of a wall, with your legs up against the wall, which can help correct blood flow to the stomach.
  • Grab some headphones: Listen to this song, which scientists have proven reduces anxiety.Graff V, et al. (2019). Music versus midazolam during preoperative nerve block placements: a prospective randomized controlled study. https://www.ncbi.nlm.nih.gov/pubmed/31320504

You might also try taking a probiotic supplement. These contain bacteria that boost gut health may help to restore a healthy balance of bacteria in your gut. Not all microbes are lions waiting to chase you down.

A limited amount of studies are investigating whether these supplements might relieve anxiety. So far, there’s some evidence they may help in rodents, but scientists have not yet confirmed this effect in humans.Kiousi DE, et al. (2019.) Probiotics in extraintestinal diseases: Current trends and new directions. DOI: https://doi.org/10.3390/nu11040788

While there are many things you can try when pushing those butterflies away, it’s most important to realize that what’s best is what works for you.

Unless butterflies become a repeated, unpleasant pattern that suggest something more complicated is afoot, just let them be. Experience them and learn to appreciate them.

They are your body’s way of letting you know that what is about to happen means as much to you as not getting eaten by lions.

To summarize: When you learn to relax and manage your anxiety, you’ll help convince your body that it’s not in physical danger.

This can help you take control of the situation and may support you not word-vomiting at a bemused would-be manager during an interview.

That said, butterflies will keep coming at you all the way through life. It might be best to see them as a pal who’s letting you know what’s important.