Here’s why your stomach acid doesn’t burn through the lining

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Stomach acid is strong enough to dissolve metal

I know what you’re thinking because I thought: if the acid in your stomach is strong enough to dissolve metal, why doesn’t it burn right through the lining of the stomach?

That’s a great question but before we get to the answer lets back up and start at the beginning.

Good digestion starts in the mouth. The more times you chew your food the less work your stomach has to do. Think of it this way, the better you chew, the better you poo. Once swallowed, food travels down a long tube called the esophagus. At the end of that tube is a small muscular valve that opens up just enough to allow the food to drop into a bath of stomach acid — splash!

This stomach acid (also known as hydrochloric acid, or HCL) needs to be strong enough to turn whatever we just ate into a liquid mush, this helps with absorption.

The stomach has been working this way since the beginning of time and you kinda have to marvel at the design. Once the food has been turned into a liquid mush it is ready to move onto the next stage.

Food drops down the shoot into a bath of acid — — splosh! Food turns into liquid mush; then mush oozes out a little at a time into the small intestine, so far so good, right?. Meh, not so fast…

The whole process of digestion hinges on this pivotal stage. But what if the stomach acid has become weak through illness, neglect, abuse, or simply through time?

If the acid isn’t strong enough, a whole chain reaction of negative events can begin to unfold. Not least, valuable nutrients will struggle to be fully absorbed. Obviously, we need these nutrients to power and rebuild our cells.


Bloating, belching, flatulence, indigestion, diarrhea, and constipation are all clues that something isn’t quite right with the stomach. In certain circumstances, a person with weak stomach acid may also suffer from heartburn. Wait a second, did you catch that?

But isn’t heartburn treated by the million-dollar antacid industry? If only it were that simple.

If this is you, my question is this: how have years of taking antacids been working for you? Has it fixed the problem or does it just keep coming back, again and again, and again?

Obviously stomach acid is strong for a reason. Some believe that antacids only add to the problem by making already low stomach acid even lower. The stomach then strives to balance itself out, but it cannot correct the problem with a belly full of alkaline pills. Now you are caught in a constant dance with yourself. Sometimes, we need to get out of the way and let the body do the job it was designed to do.

Obviously, if you are taking a prescription antacid that is something you need to work out with your doctor to ensure this approach is right for you. While you are there, it might be worth getting tested for H-pylori which is a type of bacteria ALSO known to reduce stomach acid … just sayin’.

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It's thought that a lack of stomach acid allows the valve at the end of the esophagus to open back up. This valve, also known as the lower esophageal sphincter (or LES), is a muscle that contracts much the same way the anus does. Its job is to form an important seal to keep the acid from slipping back up into the esophagus where it can cause damage and heartburn.

Some schools of thought suggest that the LES valve has some degree of sensitivity to the acid in the stomach. When the stomach acid is too low it may be fooled into opening back up. Hence, all those antacids aren’t really helping the problem and it may be worth trying a different approach. For now, the problem is much bigger than heartburn. Weak stomach acid has a domino effect throughout the remaining stages of digestion. The liquid mush we mentioned earlier becomes a semifluid mass of partly digested food. The fancy name for it is chyme or chymus. It’s then expelled by the stomach into the duodenum.

Without wanting to confuse you with lots of fancy names let’s just work with the primary rule of physics and say that all shit rolls downhill. And in this case, the liquid mush passes a whole bunch of important sensory checkpoints on the way down. These checkpoints scrutinize the quality of the mush (AKA chyme), but for now, we’ll just call it liquid mush.

In theory, if the quality of the stomach acid is good, so is the quality of the liquid mush. If not, then it’s a case of too bad, so sad, because when it comes to shit there really is no going backward.

Once our liquid mush enters the small intestine, enzymes are eagerly waiting to break things down even more. This can present a problem if the hydrochloric acid in the stomach is strong enough to do its job properly.


The three main enzymes the body uses to aid in digestion are amylase, protease, and lipase, but many other specialized enzymes also help in the process. Cells that line the intestines also make enzymes called maltase, sucrase, and lactase, and each is able to convert a specific type of sugar into glucose. We need these enzymes to help us absorb our nutrients.

Do we need to know all these terms as a layperson? Probably not, but I know it disturbs some people when I use terms like liquid mush and shit.- I digress …

Two more enzymes by the names of renin and gelatinase then come into play. Renin acts on proteins in milk, converting them into smaller molecules called peptides. These are then fully digested by pepsin. I know, right? Who thinks like this?

Gelatinase digests gelatin and collagen — two large proteins in meat — into moderately-sized compounds whose digestion is then completed by pepsin, trypsin, and chymotrypsin, producing amino acids. Yadda, yadda, yadda.


If weak stomach acid allows partially undigested food to move through the digestive system, the whole delicate balance is disrupted. A domino effect occurs as the liver, gallbladder, and pancreas also pick up on the lack of acidity in the liquid mush and react accordingly. If weak acid in the stomach isn’t doing its job optimally, it’s a safe bet that neither is anything else.

Rather than trying to bolt the stable door after the horse has fled, it might be prudent to pay particular attention to increase stomach acid. Strong stomach acid also plays an important role in protecting us from bacteria that may be on ingested food.


In some people, it’s thought that chemotherapy can reduce stomach acid. If this is you, you may notice a sudden increase in acid reflux and this becomes all the more relevant.

To recap:

We need strong stomach acid to help us break down our foods, especially proteins. Strong stomach acid also helps kill off any harmful bacteria that may come in with food. Weak stomach acid can cause a whole host of health problems.

Before we get into this next part, let me once again stress that the following information should serve as a guide only. It cannot and should not be substituted for medical advice.

Okay, here’s one way I test to see if my stomach acid is running low.

1 First thing in the morning, mix 1/4 teaspoon of baking soda in 4–6 ounces of room temp water.

2 Drink the baking soda on an empty stomach.

3 Time how long it takes before you belch.

4 If you have not belched within five minutes, stop timing.

In theory, if your stomach is producing adequate amounts of stomach acid you’ll likely belch within two to three minutes. Early and repeated belching may be due to excessive stomach acid (but don’t confuse these burps with small little burps from swallowing air while drinking the solution). Any belching after 3 minutes indicates a low acid level.

Because we are all uniquely different, timeframes may vary a little. This test is only a basic indicator and you might want to do more testing to determine the level of your stomach acid with your doctor. This test is a guide and not to be considered accurate enough to rule out low stomach acid. To rule out low stomach acid you will need to also try what’s called the Heidelberg test or Betaine HCL challenge test.


If stomach acid is found to be too low, there are lots of ways to increase it. One is to use a supplement called Betaine HCL, (which is best taken with protein).

Another is to take a tablespoon of apple cider vinegar (ACV) 10 mins before each meal to help increase stomach acid. Simply mix the ACV in 8 oz. of room temp water and drink (for health, not taste).

If your doctor says it’s okay to do so, you can raise your stomach acid by mixing one freshly squeezed lemon, 4 oz. of water, approximately three knuckles of chopped raw ginger, and a half teaspoon of sea salt.

Leave this mixture to pickle for a few days and then take a teaspoon of the mixture before meals. It’s an acquired taste, but if your stomach acid is low your body may even begin to crave it. As with anything new, start with a small test dose and go slow.

If you take only one thing away from this, then let it be the value of your stomach acid. Putting our health back together is a process. And slowly, piece by piece, blog by blog, we are now bringing pieces of the puzzle into view.

So you are probably still wondering why strong stomach acid doesn’t burn through the stomach. The short answer is that the stomach has a mucous membrane. It’s a wall of cells that are constantly replaced; as one layer burns through, another steps in to replace it.

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I aim to provide engaging content that's enjoyable to read. I’m also the author of the Amazon bestseller “The Healing Point.”

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