Why is spoiled food dangerous if our stomach acid can basically dissolve almost anything organic



Pretty much the title.

If the stomach acid is strong enough to dissolve food, why can’t it kill dangerous germs that cause all sorts of different diseases?

In: Biology

Not all bacteria go down to the stomach, some stay in your mouth.

Bacteria can also produce toxins on the food while it spoils, even if the stomach acid kills the bacteria, the toxins can still poison you.

Also some bacteria are just acid resistant.

Well first, stomach acid can kill many germs but not all of them. Second, in some cases of food-borne illness, it’s not the germs themselves that make you sick but toxins created by the germs, and stomach acid doesn’t do anything to those toxins. This is why can’t eat spoiled food even if it’s cooked. Yes, cooking may kill the germs, but it still leaves the toxins that make you sick.

Still early in the thread to tell that not the bacteria/germs are the biggest problem but the substances (toxins) they are producing… you can’t wash them away or destroy them with high temperature.

It is called food POISONING for a reason.

One thing I haven’t seen mentioned is that most food based illness in the developed world isn’t due to bacteria, but norovirus. Norovirus will quite happily move through your stomach to your small intestine where it sets up replicating and irritating your gi tract. Then when it’s done enough damage it exits (in both directions) and gets spread onto every surface in your bathroom when you flush the toilet. Anyone who touches those surfaces can then infect themselves by putting their fingers or something they touch in their mouth, or infect others by failing to wash their hands (with bleach; norovirus largely ignores soap) and then serving/cooking their food.

The same way we claim a dogs mouth is cleaner than a humans. The bacteria in a dog’s mouth isn’t as harmful to us as some of the bacteria that grows in our own…especially the ones that rot our teeth and inflame our gums. As food is consumed by bacteria in the fridge or counter, it’s releasing toxins that affect us when we eat them. Those bacterial growths and their toxins are what make us sick, not the food itself.

A lot to unpack here but here it goes:

First, there are two main ways that bacteria cause foodborne illness: intoxications and infections

1. Intoxications: Bacteria grow in the food and make toxins, and then you eat the food with the toxin and get sick. The toxins are acid resistant enough that the stomach acid doesn’t do anything to them.

2. Infection: Stomach acid can and will kill some of the germs, but enough survive to get into your intestines and cause an infection.

Edit: spelling, grammar

People have touched on almost everything, but it effectively boils down to a few factors;

– the bacteria type
– does the bacteria produce a toxin that *isn’t* broken down by stomach acid?
– how *much* bacteria are you getting in the bolus of food? One of the things I hadn’t seen addressed here is that you can get sick if the number of colony forming units (CFUs) outnumber the amount of acid that gets them. If you wanted to raid a castle that had a moat around it, and you had an unlimited number of soldiers, and you were a psychopath…well, just continue throwing soldiers at the castle until the moat fills up with dead people, and then climb over it. Sure, lots of bacteria will die in that acid bath…but some might make it through the gates on the dissolving bodies of their comrades and make a nice home in your guts.

Ever looked at your poop after eating corn? Some stuff our stomachs can’t deal with conpletely

For one thing, stomach acid isn’t actually super strong. It’s a form of Hydrochloric Acid, but it is dilute. If you’ve ever had to clean up vomit, you’ll know that it doesn’t just burn through everything it touches.

As others have pointed out too, it’s not just the living parts that are dangerous.

Because our stomachs aren’t actually that acidic! We are omnivore so we have a medium acidity and we cook our food and chew it well, unlike cats and dogs who don’t cook or chew. Their stomachs are wayyyy more acidic than ours and thus kill much more bacteria.

ELI5 by species:

E. Coli produce certain anti-acids so they can survive the stomach. They have like 3 so if one fails the others kick in. Now that’s gangster! So make sure you wash your hands after you poop. There is a super version(triple OG E. Coli(entiritis) that kills instead of just making you sick.

The most common kind of food poisoning bacteria Campylobacter is so devious it hijacks a ride through a protozoa(which moves away from acid) to make you run to the bathroom every 15 minutes after you’re infected.

Deadly C. Botulinum form spores which are like invincible eggs that hatch when they are good and ready to go(safe from heat and acid). They can die but their poop(the botulism toxin) is deadly and used by doctors to remove wrinkles by paralyzing face muscles. Not good if it’s paralyzing your diaphragm or heart after too much gets in your system.

Cholera mostly die but just a little make it thru to your intestines then they bounce back to screw you over. You ever see how bacteria reproduce? It’s exponential so once a few get thru you’re screwed until your immune system kicks in.

There is an algae that is poisonous and fish are left with it’s toxins. You eat that don’t worry about an organism the toxins will kill you. Yeah, if you haven’t caught on by now microorganisms can poison you with their poop. Don’t swim in the red tide either. Just don’t.

Listeria gives zero farts(ELI5 word hehe) about stomach acid, kind of like E. Coli but they need a certain ingredient to do it. So if you eat a food high in glutamate(cheese, nuts, processed meats) they will be happy you are helping them resist the acid.

Staph will give you a boil but just die when you cook it. What doesn’t die? The poop it released into your food before you cooked it which is toxic. They’re a huge fan of cookouts. The human side of things it’s hard to throw out those grilled burgers. I for one have taken many many chances.

Salmonella doesn’t play games, it lowers it’s own acidity to feel right at home. Kind of like a bullshark switches from salt to fresh water to just generally be a bully that can survive anywhere.

The bottom line? Practice safe food handling techniques. Keep food refrigerated and throw it out when it’s expired. Refrigerate cooked food within 3 hours or keep it at a temperature bacteria won’t grow(yeah, it will dry out and start to suck at that point, so better to just refrigerate after a certain time). Reheat food thoroughly.

I have an iron stomach, I can eat a pizza that has been sitting in the oven from last night. But if one of those clever bacteria survived, it’s FML(fart my life).

Hang on for a minute:

>…if our stomach acid can basically dissolve almost anything organic

This is not true. There are a lot of organic things that a human stomach can’t “dissolve” very efficiently. That includes grass, wood, bone, etc. Some animals can handle those things, but humans cannot.