Somewhere, right now, someone is staring into the fridge at a bowl of Jell-O that refuses to set. They followed the box exactly.
The only thing they added was fresh pineapple, because it looked festive.
Quick answer: Protease is the name for any enzyme that breaks protein down. It cuts the long chains that proteins are made of into shorter pieces (peptides) and finally into single amino acids, which is the only form your body can absorb and use. Your stomach and pancreas make their own proteases every day. Some foods, like fresh pineapple, papaya and kiwi, carry proteases too, and many digestive enzyme supplements include protease to help with the protein in a meal.
The pineapple is the culprit. It’s full of an enzyme that chops up the gelatin protein faster than it can firm up.
That enzyme is a protease, and the same kind of enzyme is working in your stomach every time you eat eggs, chicken, fish, beans, yogurt or a steak.
It’s also one of the four enzymes in the blend inside Eat Anything Rx, even if it sounds less like an enzyme and more like a clause in a rental agreement.
What is protease, in plain English?
Start with the name, because it gives the whole game away. “Prote-” is protein. “-ase” is the ending scientists give to enzymes.
So a protease is, quite literally, a protein enzyme. (You’ll also see “proteolytic enzyme” and “peptidase.”
Same family, fancier hat.)
Proteins are long chains of smaller building blocks called amino acids, about 20 different kinds, linked end to end and then folded into a tight bundle.
Picture a zipper that’s been zipped shut and then scrunched into a ball.
of protein a day is what the average American adult eats. That’s a lot of zippers for one enzyme family to open, every single day.Source: USDA, What We Eat in America, NHANES August 2021–August 2023 (77.1 g, adults 20 and over)
Your body can’t absorb that bundle whole. It has to be unfolded and then unzipped, link by link, into pieces small enough to cross the gut wall.
That unzipping is what protease does. It breaks the bonds between amino acids (peptide bonds, if you want the exam answer).
Once those amino acids are absorbed, your body rebuilds them into its own proteins: muscle, skin, hair, hormones and, fittingly, more enzymes. Protein you can’t unzip is protein you can’t use.
Where does your body make protease?
Protein digestion is a relay, not a single event. If you’ve seen our videos, picture the kitchen crew: different stations, each handling one stage of the prep.
One detail I love: your body makes these proteases in an inactive form and only switches them on once they reach the food. Pepsin starts life as pepsinogen and waits for stomach acid.
Trypsin leaves the pancreas as trypsinogen, gets activated in the small intestine, and then activates the others.
It’s the knife block with the safety catch on, because a protein-cutting enzyme that switched on too early would start in on the pancreas itself.
| Station | Protease | What it does |
|---|---|---|
| Stomach | Pepsin | Makes the first rough cuts. Stomach acid unfolds the protein bundles and switches pepsin on. |
| Pancreas (working in the small intestine) | Trypsin, chymotrypsin, elastase, carboxypeptidase | The main crew. Each one cuts at different spots along the chain, so together they reduce protein to short fragments. |
| Small intestine lining | Brush-border peptidases | The finishing station. Trims the last fragments into single amino acids and tiny two- and three-link pieces that can be absorbed. |
That would be a very bad day at the office.
Most of the heavy lifting happens in the small intestine.
The stomach gets things started, but pancreatic proteases do the bulk of the work (a 2007 review by Whitcomb and Lowe in Digestive Diseases and Sciences is a good deep dive if you enjoy that sort of thing).
Why a protein-heavy meal can feel so heavy
If a steak dinner has ever seemed to move in and sign a lease, there’s a reason.
First, the queue. Protein and fat both slow down how quickly your stomach empties. That’s part of why they keep you full, which is usually a feature.
But a big, rich meal, say a steak, a creamy side and a buttery dessert, gives the whole relay a lot of work at once. Nothing’s broken.
There’s just a line at the kitchen door. We dig into that feeling in why food can sit in your stomach for hours and why you can feel heavy after eating very little.
3 kitchen tricks, courtesy of protease
- Making Jell-O with pineapple? Use canned. The heat treatment has already switched off the bromelain, so your dessert will actually set.
- Tough cut of meat? A marinade with fresh pineapple, papaya or kiwi starts the protein prep for you. Keep it short, though. Leave it overnight and the texture goes mushy.
- Fruit and yogurt for tomorrow? Add the fresh kiwi or pineapple in the morning, not the night before, or you’ll open the fridge to something oddly soft.
Second, what slips through. Whatever protein isn’t fully broken down and absorbed in the small intestine keeps going to the colon, where gut bacteria ferment it. Bacteria fermenting carbohydrate mostly make odorless gases.
Bacteria fermenting protein make, among other things, hydrogen sulfide. That’s the rotten-egg one.
If your digestion after a big protein meal is, let’s say, socially memorable, that’s usually the mechanism.
So the logic behind adding protease at mealtime is the same logic as every good enzyme: help break more of the food down up top, so less of it reaches the bacteria downstairs.
It’s why Eat Anything Rx goes down with your first bite.
Foods that naturally contain protease
A few fruits and plants make their own proteases, and they have some of the best party tricks in the kitchen.
- Pineapple (bromelain). The Jell-O saboteur. It’s also why a big bowl of fresh pineapple can leave your tongue a little tingly: it is, very gently, working on you back.
- Papaya (papain). This is the enzyme in powdered meat tenderizer. Sprinkle it on a steak and it starts the protein prep before the pan is even hot.
- Kiwi (actinidin). The reason some marinades and fruit-and-yogurt combinations go oddly soft if you leave them sitting.
- Figs and ginger (ficin and zingibain). Less famous, same idea.
One catch: heat switches these enzymes off. Canned pineapple is heat-treated, which is why it sets in gelatin just fine while fresh pineapple turns it to soup.
Cooked fruit is still good food. It just isn’t bringing any working protease to the table.
What a protease supplement is (and isn’t)
A digestive protease supplement is simply extra protease you swallow with a meal, so it can go to work on the protein in that meal.
of your daily calories can come from protein, according to the official healthy range for adults. At the high end, that’s a lot of steak, eggs and Greek yogurt for your protease to unzip.Source: National Academies (Institute of Medicine), Dietary Reference Intakes, Acceptable Macronutrient Distribution Range
Supplement proteases come from a few sources: plants (bromelain, papain), food-grade fungi grown by fermentation, and animal pancreas (sold as pancreatin).
It only works when it meets the food
An enzyme is a tool, and a tool only works when it’s touching the job. That means taking it just before or with the first bites of the meal.
Taken hours later, it’s the kitchen crew arriving after dinner service has closed.
It also has to get through the stomach in working order, which we cover in do digestive enzymes survive stomach acid.
Protease is one tool, not the whole toolbox
Protease works on protein, and only protein.
It does nothing for the starch in the bread, the fat in the butter, the fiber in the salad, the fructose in the fruit or the sugars in the beans.
That’s the unfair reputation enzymes pick up: someone buys a single enzyme, eats a meal whose real trouble is something else entirely, and decides enzymes don’t work.
It’s a bit like hiring a great butcher and wondering why the salad is still unwashed.
That’s why Eat Anything Rx pairs protease with enzymes for everything else on the plate. You may also see protease sold for taking between meals.
That’s a different category of supplement with different claims, and not what this article is about. Here we mean one thing: protease with food, for digestion.
What does the research say?
The physiology of protease is textbook stuff and not in dispute. Your body relies on it for every gram of protein you digest.
The research on supplemental enzymes is newer and more modest, and it’s worth being straight about it.
Studies of multi-enzyme blends, including a 2018 placebo-controlled trial in the Journal of Medicinal Food in adults with recurring indigestion, have reported less bloating, gas and after-meal fullness with the enzyme blend than with placebo.
That was a different formula from ours, so it tells you enzymes with meals is a reasonable idea, not how any particular product will work for you.
And to be clear: no clinical trial has tested the protease in Eat Anything Rx on its own.
“I ate a meal that has been known to cause digestive issues for me. But after taking this product, I had zero, and I mean ZERO issues. Eager to try it when I eat spaghetti sauce with meat. I’m hopeful!”
— Joyce A Meyer Ponzi, Amazon Verified Purchase · Read more reviews
It’s there because protein is on almost every plate, and a blend built for whole meals would be incomplete without it.
The ingredient in our formula with the strongest published human research is actually xylose isomerase, the fructose enzyme.
Protease and dairy
Dairy is a three-part food: milk protein (casein and whey), milk fat, and milk sugar (lactose). Protease works on the protein. Lipase works on the fat.
So Eat Anything Rx supports digestion of the protein and fat in a dairy-rich meal, like a cheesy pasta or a cream sauce.
The bottom line
Protease is the enzyme that unzips protein into amino acids your body can actually use.
You make plenty of your own, in the stomach, the pancreas and the lining of the small intestine, and a few fruits bring their own to the party (and ruin the occasional Jell-O).
A protease supplement taken with a meal adds extra help for the protein on the plate.
It won’t do the job of the other enzymes, it doesn’t touch lactose, and it works only when it meets the food.
If big, protein-heavy meals are the ones that tend to linger, try Eat Anything Rx with them.
And if you feel full after just a few bites no matter what you eat, that’s worth reading about, and worth a conversation with your doctor.
For how enzymes and probiotics divide the work, see digestive enzymes vs. probiotics. For the full blend protease belongs to, see what is the APLC enzyme blend.
Protease, plus the rest of the crew
Real meals are never just protein. Eat Anything Rx puts protease in one capsule alongside the enzymes for everything else on the plate.
- ✓APLC blend: amylase, protease, lipase and cellulase
- ✓Xylose isomerase for fructose
- ✓Alpha-galactosidase for beans and broccoli
- ✓Lacto-Wise probiotic and prebiotic
Common questions
What is protease?
Protease is any enzyme that breaks down protein. It cuts the chains that proteins are made of into smaller peptides and then single amino acids, the form your body can absorb. Your stomach, pancreas and small intestine all make proteases, and some foods and digestive supplements contain them too.
What does protease do in digestion?
It breaks the bonds between amino acids so dietary protein can be absorbed. Pepsin in the stomach makes the first cuts, pancreatic proteases such as trypsin and chymotrypsin do most of the work in the small intestine, and enzymes in the intestinal lining finish the job.
Which foods naturally contain protease?
Fresh pineapple (bromelain), papaya (papain), kiwi (actinidin), figs (ficin) and ginger (zingibain) are the best-known examples. Heat switches these enzymes off, so cooked or canned versions do not bring working protease with them.
Is bromelain the same as protease?
Bromelain is a type of protease: the one that comes from pineapple. Protease is the family name, and bromelain, papain, pepsin and trypsin are all members of it.
When should you take a protease supplement for digestion?
With food. A digestive protease works on the protein in the meal it meets, so take it just before or with the first bites, following the label. Eat Anything Rx is directed as one to two capsules before each meal.
Does protease help digest dairy?
It helps with the protein side of dairy. Protease breaks down milk proteins (casein and whey), and Eat Anything Rx pairs it with lipase for milk fat, which supports digestion of dairy-rich meals like a cheesy pasta or a cream sauce.
Why does fresh pineapple stop gelatin from setting?
Fresh pineapple contains bromelain, a protease that breaks down the protein in gelatin before it can firm up. Canned pineapple is heat-treated, which deactivates the bromelain, so it sets normally.
By Dave Sherwin, PN1 Certified Nutrition Coach
More in the enzyme series: What Is Amylase? The Enzyme That Breaks Down Starch · What Is Cellulase? The Fiber Enzyme Humans Don’t Make